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9400 LTE LA3.0 Radio Algorithms and Parameters description - Page 1All Rights Reserved © Alcatel-Lucent 2011

All Rights Reserved © Alcatel-Lucent 2011

9400 LTE LA3.0 Radio Algorithms and Parameters

description

STUDENT GUIDE

TMO18315 D0 SG DEN I 5.0

All rights reserved © Alcatel-Lucent 2011 Passing on and copying of this document, use and communication of its contents

not permitted without written authorization from Alcatel-Lucent



9400 LTE LA3.0 Radio Algorithms and Parameters description

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Terms of Use and Legal Notices

Switch to notes view!1. Safety WarningBoth lethal and dangerous voltages may be present within the products used herein. The user is strongly advised not to wear conductive jewelry while working on the products. Always observe all safety precautions and do not work on the equipment alone.

The equipment used during this course may be electrostatic sensitive. Please observe correct anti-static precautions.

2. Trade MarksAlcatel-Lucent and MainStreet are trademarks of Alcatel-Lucent.

All other trademarks, service marks and logos (“Marks”) are the property of their respective holders, including Alcatel-Lucent. Users are not permitted to use these Marks without the prior consent of Alcatel-Lucent or such third party owning the Mark. The absence of a Mark identifier is not a representation that a particular product or service name is not a Mark.

Alcatel-Lucent assumes no responsibility for the accuracy of the information presented herein, which may be subject to change without notice.

3. CopyrightThis document contains information that is proprietary to Alcatel-Lucent and may be used for training purposes only. No other use or transmission of all or any part of this document is permitted without Alcatel-Lucent’s written permission, and must include all copyright and other proprietary notices. No other use or transmission of all or any part of its contents may be used, copied, disclosed or conveyed to any party in any manner whatsoever without prior written permission from Alcatel-Lucent.

Use or transmission of all or any part of this document in violation of any applicable legislation is hereby expressly prohibited.

User obtains no rights in the information or in any product, process, technology or trademark which it includes or describes, and is expressly prohibited from modifying the information or creating derivative works without the express written consent of Alcatel-Lucent.

All rights reserved © Alcatel-Lucent 2011

4. DisclaimerIn no event will Alcatel-Lucent be liable for any direct, indirect, special, incidental or consequential damages, including lost profits, lost business or lost data, resulting from the use of or reliance upon the information, whether or not Alcatel-Lucent has been advised of the possibility of such damages.

Mention of non-Alcatel-Lucent products or services is for information purposes only and constitutes neither an endorsement, nor a recommendation.

This course is intended to train the student about the overall look, feel, and use of Alcatel-Lucent products. The information contained herein is representational only. In the interest of file size, simplicity, and compatibility and, in some cases, due to contractual limitations, certain compromises have been made and therefore some features are not entirely accurate.

Please refer to technical practices supplied by Alcatel-Lucent for current information concerning Alcatel-Lucent equipment and its operation, or contact your nearest Alcatel-Lucent representative for more information.

The Alcatel-Lucent products described or used herein are presented for demonstration and training purposes only. Alcatel-Lucent disclaims any warranties in connection with the products as used and described in the courses or the related documentation, whether express, implied, or statutory. Alcatel-Lucent specifically disclaims all implied warranties, including warranties of merchantability, non-infringement and fitness for a particular purpose, or arising from a course of dealing, usage or trade practice.

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Course Outline

About This CourseCourse outlineTechnical supportCourse objectives

1. Topic/Section is Positioned HereXxxXxxXxx

2. Topic/Section is Positioned Here






Section 1.

Module 1. eUTRAN Parameter Introduction

Module 2. Radio Ressources Management

Module 3. Session Management

Module 4. Mobility Management




6

Course Outline [cont.]






7

Course Objectives


Welcome to 9400 LTE LA3.0 Radio Algorithms and Parameters description

Upon completion of this course, you should be able to:




8

Course Objectives [cont.]






9

About this Student Guide

Switch to notes view!Conventions used in this guide

Where you can get further information

If you want further information you can refer to the following:

Technical Practices for the specific product

Technical support page on the Alcatel website: http://www.alcatel-lucent.com

Note Provides you with additional information about the topic being discussed. Although this information is not required knowledge, you might find it useful or interesting.

Technical Reference (1) 24.348.98 – Points you to the exact section of Alcatel-Lucent Technical Practices where you can find more information on the topic being discussed.

WarningAlerts you to instances where non-compliance could result in equipment damage or personal injury.




10

About this Student Guide [cont.]






11

Self-assessment of Objectives

At the end of each section you will be asked to fill this questionnairePlease, return this sheet to the trainer at the end of the training


Instructional objectives Yes (or globally

yes)

No (or globally

no) Comments

1 To be able to XXX

2

Contract number :

Course title :

Client (Company, Center) :

Language : Dates from : to :

Number of trainees : Location :

Surname, First name :

Did you meet the following objectives ?Tick the corresponding box

Please, return this sheet to the trainer at the end of the training




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Self-assessment of Objectives [cont.]


Instructional objectives Yes (or Globally

yes)

No (or globally

no) Comments

Thank you for your answers to this questionnaire

Other comments

Section 1 · Module 1 · Page 1

All Rights Reserved © Alcatel-Lucent 2011Issue

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Module 1eUTRAN Parameter Introduction

Issue

Section 1

9400 LTE LA3.0 Radio Algorithms and Parameters descriptionTMO18315 D0 SG DEN I 5.0




· 9400 LTE LA3.0 Radio Algorithms and Parameters description· eUTRAN Parameter Introduction1 · 1 · 2

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First editionLast name, first nameYYYY-MM-DD01

RemarksAuthorDateEdition

Document History





Module Objectives

Upon completion of this module, you should be able to:

Describe the eNodeB configuration model Describe the parameter propertiesList the purpose and types of Licensing





Module Objectives [cont.]






Table of Contents

Switch to notes view! Page

1 Configuration Management Overview 71.1 Configuration Management Component 81.2 eNB Configuration Model 91.3 RDNID And Configuration ID Parameters: Example 101.4 LTE Parameters Templates And Properties 111.5 LTE Parameter Properties 121.6 Licensing Purpose 131.7 Feature License Process 141.8 Licensed Features In LA3.0 15

1.8.1 Example: 16Self-assessment on the Objectives 17End of Module 18





Table of Contents [cont.]








1 Configuration Management Overview








1.1 Configuration Management Component

OAM Network -IP

WPS Configuration Tool

SAM- LTE

NEM

eNB

Backhaul Network- IP

eUtran Configuration Snapshot file

eUtran Configuration Work Order

eNB Configuration Modification request

The principal configuration management physical components are:

IP Networks – Used to transport data among the OAM Configuration Management components.

eNodeB – The radio base station provides the radio cells, terminates the air interface associations with

the UEs, supports backhaul to the evolved Packet Core Network. The eNodeB also accepts configuration

information from the SAM and provides other OAM services.

Service Aware Manager (SAM) – The 5620 SAM is a system that is designed to manage Alcatel-Lucent

network elements, or NEs, such as routers and switches. In Release LA3.0, the 5620 SAM also supports the

management of eNBs, and replaces the eXterded Management System (XMS) that was used to manage the

eNBs in earlier LTE releases. In the management of eNBs, the 5620 SAM serves as a system for sending

updates of configuration data, capture of configuration change requests, fault management, etc. This

function is a part of the Operations and Management Center (OMC).

Wireless Provisioning System (WPS) – A system that supports capture of network element configuration

data, and is used by the operations team for off-line preparation of configuration changes

Network Element Manager (NEM) – An application that can run on a laptop and can create and load an

object/parameter file into the eNodeB. The file is used to set the initial value of LTE I&C parameters. NEM can be used at the

eNodeB location, and it can also update some parameters remotely.

As indicated in the slide, configuration management snapshots of the eUTRAN can be imported from

the 5620 SAM into the WPS system. Configuration changes can be indicated in the WPS system, and then a

configuration management work order file can be exported from WPS to the 5620 SAMS system.

Configuration changes are then sent from SAM to affected eNodeBs.







1.2 eNB Configuration Model

Containing Object

AnotherContained

Object

AnotherContained

Object

Contained Object

Some other

Objects

Containing Object

1

1

1 0…3

Contained Object

ContainingObjectNode with the CM tree Leaf withing the CM tree

One and only one instance permitted, per containing

object instance.

From zero to three instances (rdnids) permitted, per containing object instance.

Object from elsewhere in containment hierarchy

The object oriented approach of the CM is used to complement the LTE software architecture.

The model consists of objects that have associated parameters and may contain other objects.







1.3 RDNID And Configuration ID Parameters: Example

LogicalChannel

ConfSecurity

Conf

DedicatedConf

RohcConf

PdcpConf

RlcConf

SigRadioBearerConf

TrafficRadioBearer ConfUeTimers

RlcUmConf RlcAmConf

2..2 1..255

1..8

1..8

0..1

1..4

0..1

0..1 0..1

Multiple instances are possible for many of the objects:

An rdnid parameter uniquely identifies the instance of an object. For example, rdnid = 0 identifies the

first instance of the object, rdnid = 1 identifies the second instance of the object, etc.

A configuration ID parameter assigns an instance of another object to the object that it is an attribute of.

Each of the up to 255 instances of object TrafficRadioBearerConf has four ConfId parameters (eNB/UE,

UL/DL) that identify instances of LogicalChannelConf, PdcpConf, and RlcConf that the current instance

points to.

For example, if parameter eNBDlRlcConfId is set to “BTSEquipment/0 Enb/1 DedicatedConf/0

RlcConf/2”, then the current instance of TrafficRadioBearerConf points to the 3rd instance of object

RlcConf (for the eNodeB in the Downlink).

Note also that in addition to an rdnid parameter, some objects also have associated uniqueName

parameters.







1.4 LTE Parameters Templates And Properties

Parameter The Name of the parameter is provided here

Object The range and unit of the parameter

Range & Unit The range and unit of the parameter

Class/ Category The Class and the Category of the parameter

Value The default or recommended value parameter

feature Feature the parameter is directly associated with (if applicable)

The parameter properties are summarized in a table as follows:

Category: of a given parameter will be indicated to be one of the following:

I&C – NEM: These parameters are set using a Local Maintenance Terminal (LMT) during the Installation and the Commissioning of the eNodeBs.

I&C – OMC: These parameters configure the eNB and are provided by the customer. They are set from the 5620 SAM (typically using files prepared with the WPS system).

Fixed - the value of the parameter is fixed in the sense that the value should not change from cell to cell.

Optimization - Tuning: The values of these parameters generally change from cell to cell (based on the size and the topology of the cell). These parameters require a fine tuning and are generally performance impacting parameters (in the sense that they are likely to have an important impact on end-user performance), and their tuning may involve a tradeoff (throughput/quality, cell coverage/interference to the neighboring cells, etc.).

Optimization - Selection: The values of these parameters generally change from cell to cell (based on the size and the topology of the cell). The value of these parameters is selected from a set of a few possible values. These parameters are generally performance impacting parameters.

• Parameter Value: This will normally be the default or latest recommended value for the parameter.

Some parameter values include an admonition in red text that the value should not be changed by the

operator.

• Feature Number: When possible, a reference is provided to the LTE feature number that caused the

parameter to be added or that altered the parameter’s use. When a parameter is related to several

features, multiple feature numbers may be indicated. Some parameters are not associated with a

specific feature, and, in the case of these parameters, the feature number entry will be blank.







1.5 LTE Parameter Properties

Class (A/0, B/2, C/3) :Each parameter is assigned to a class according to the impact that results when the parameter value is modified (or created/deleted for an associated object).

Modification/ Creation/ Deletion Class A/0 Class B/2 Class C/3

Full eNB Reset YesNo

(Object reset only)

No

OaM Interfaces available No Yes Yes

Service Impact Yes Yes No

Class A: The modification/creation/deletion of these parameters requires a full eNodeB reset before the change will take effect. The eNB OA&M interfaces are unavailable during the reset.

Class B: The modification/creation/deletion requires internal resource unavailability in the eNB, which leads to service impact. The eNB OA&M interfaces remain available. The precise service impact can vary between parameters as outlined below. In general for Class B changes, the object whose parameter value is to be changed will be reset when the modified data is downloaded to the eNB.

Class C: The modification/creation/deletion is taken into account by the eNB without any impact on services. Two sub-categories are also defined in the LA3.0 release:

C--Immediate-propagation: No temporary service impact. But any update that, in principle, reconfigures any existing established activities that are supervised by the eNodeB will be cascaded immediately to all those activities. C--New-set-ups: No temporary service impact. In general, the new parameter value will take effect only for new established activities. However, a parameter that affects any information that is broadcast by the eNodeB may be cascaded immediately via the appropriate broadcast mechanism.






1.6 Licensing Purpose

Radio License ManagerPool of features tokens

(credited token)

Config. Management eNB(s) feature activation

controlled via specificLicensing parameters (Consumed Tokens)

Feature License(Tokens/ RTUs

purchased by operator)

SAM

Comparing available “Rights to use ”Withthe SUM of optional features configured

Feature “activated” =1 Token

Feature “not activated” = 0 Token

Capacity Licensing was introduced as a method of reducing initial costs to customers.

Some eNodeB resources can be limited and monitored individually. In this way, the eNodeB capacity can

be measured and restricted under the terms of a licensing agreement. As network demands increase, the

eNodeB license capacity can be increased up to the maximum hardware capacities.

A license is generated for one specific SAM and contains the set of tokens that can be distributed to all

the eNodeBs supervised by the SAM.

The tokens represent the sum of the feature values that can be manually applied to the group of eNodeBs

in a RAN.

Capacity licensing allows the operator to reduce initial costs by tailoring its network capacities to meet

its current network requirements. As network demands increase, the license capacity can be increased

up to the maximum hardware capacities.

Feature licensing gives customers the rights to choose from a list of options,which features they require.

Customers limit their requirements to their needs.






1.7 Feature License Process

We need the following feature licenses:• 300 licenses for mobility LTE>> UTRA• 500 licenses for SON• 500 license for ANR

Operator Request

Purchase Order for:• 300 licenses for mobility LTE>> UTRA• 500 licenses for SON• 500 license for ANR

Purchase Order for:• 300 licenses for mobility LTE>> UTRA• 500 licenses for SON• 500 license for ANR

LKDI

License File content:• 300 licenses for mobility LTE>> UTRA• 500 license for ANR

SAMLicenses could be enabled on 500 eNBfor ANR et 300 eNBfor mobility LTE>> UTRA






1.8 Licensed Features In LA3.0





1.8 Licensed Features In LA3.0

1.8.1 Example:





Self-assessment on the Objectives

Please be reminded to fill in the formSelf-Assessment on the Objectivesfor this moduleThe form can be found in the first partof this course documentation





End of ModuleeUTRAN Parameter Introduction





Module 2Radio Ressources Management

Issue

Section 1





· 9400 LTE LA3.0 Radio Algorithms and Parameters description· Radio Ressources Management1 · 2 · 2

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Document History





Module Objectives


Describe LTE parameters related to eNB radio resource Management aspects.List the different features supported in LA3.0 within eUTRAN.











Table of Contents


1 MIMO and Transmission Mode 71.1 Radio Resource Management 81.2 Transmission Evolution Evolution 91.3 Transmission Mode Configuration 10

1.3.1 macMIMOModeDl Parameter 111.3.2 Rank And PMI Management 13

1.4 TM3 141.5 TM4 16

1.5.1 Codebook Configuration 171.5.1.1 dlMIMODefaultCodeBook 18

1.5.2 Basic LA3.0 TM4 Mixed Mode 191.5.2.1 TM4 mixed Mode CL-MIMO Parameters 21

2 Measurement Management 222.1 Measurement Management 23

2.1.1 PUSCH Configuration For Aperiodic CQI 242.1.2 CQI (Channel Quality Indicator) 26

2.1.2.1 Sub-Band CQI 27Subband Index With 5 Mhz 28Subband index with 10 Mhz 29Subband index with 20 Mhz 30

2.1.2.2 Wide Band SINR 312.1.3 PUSCH Configuration For Aperiodic CQI 32

3 Schedulers 333.1 Dynamic Resource Allocation & Packet Scheduling 34

3.1.1 Schedulers Principles 363.1.1.1 TimeFrequencyResBlockOccupancy Matrix 373.1.1.2 Pre-booking and Scheduling stages 38

3.2 Downlink Scheduler 393.2.1 Signaling Radio Bearer Parameter 413.2.2 DL Static Scheduler 423.2.3 DL Semi-Static Scheduler 43

3.2.3.1 D-BCH Scheduling 44SIB1 Scheduling 45SIB2,…SIB8 Scheduling 46sibClass1,2,3 Target MCS Parameters 47SIB Configuration: Data Model: Periodicity 48SIB Configuration: Data Model: Target MCS 49ALU LA3.0 Configuration Values 50SI-Messages Scheduling 51SI-Message Scheduling 52SI-Message Scheduling 53numberRBnotforSIB Parameter 54

3.2.3.2 PCCH Scheduling 55pagingForceMCSmin Parameter 56

3.2.4 DL Dynamic Scheduler 573.2.5 DL Fairness Factor 583.2.6 Resource Block Group Allocation 59

3.3 UL Scheduler 603.3.1 UL Static Scheduler 623.3.2 UL Dynamic Scheduler 65

3.3.2.1 Alpha Fairness Scheduler 664 Physical Channels Configuration 67

4.1 Radio Resources Unit Definition 684.2 Reference Signal 694.3 Synchronization Signals 70







4.4 The Physical Broadcast Channel (PBCH) 714.5 PCFICH 72

4.5.1 cFI 734.6 PDCCH 75

4.6.1 DCI 784.6.2 UE specific and Common Search Spaces Parameters 79

4.7 PHICH 804.8 The Physical Downlink Shared Channel (PDSCH) 824.9 Sounding Reference Signal 83

4.9.1 SRS Related Parameters 854.10 Physical Uplink Control Channel (PUCCH) 86

4.10.1 Scheduling Request Over PUCCH 875 Transmit Power 88

5.1 Downlink Transmit Power 895.1.1 cellDLTotalPower Parameter 905.1.2 Reference Signal Power Setting 915.1.3 Synchonization Signals Power Setting 93

5.2 PBCH 945.3 PCFICH Power Setting 965.4 PHICH Power Setting 985.5 PDCCH Power Setting 100

5.5.1 pDCCHPowerOffsetSymbol1 & pDCCHPowerOffsetSymbol2&3 1025.6 PDSCH Power Setting 1035.7 PDCCH Power Control 1055.8 Downlink Power Budget 107

5.8.1 RE Distribution in slot 0 & 1 of Subframe 0 (5 Mhz) 1096 Uplink Power Control 110

6.1 PUCCH Power Control 1116.2 PUSCH Power Control 113

6.2.1 p0NominalPUSCH & p0UePUSCH Parameters 1166.2.2 FilterCoefficient & pUSCHPowerControlAlphaFactor Parameters 117

6.3 Fractional Power Control 1186.3.1 SINR Target Computation 1196.3.2 SIR Target Vs UL Pathloss Simulation 1216.3.3 Fractional Power related parameters 123

7 Link Adaptation 1257.1 Link Adaptation Process 1267.2 macOuterLoopBlerControlTargetBler (Traffic & Signaling) 1277.3 cQIToSINRLookUpTable for DL Operations 1287.4 dlMCSTransitionTable 1297.5 Bloc Error Rate Loop Control 1317.6 Modulation TBS index for DL MCS 1327.7 SINR-to-MCS Look Up Table for UL Operations 1337.8 Modulation TBS index for UL MCS 134

8 H-ARQ 1358.1 H-ARQ Principle 1368.2 H-ARQ Process in UL & DL 137

8.2.1 PDSCH H-ARQ Timing 1388.2.2 PUSCH H-ARQ Timing 1398.2.3 H-ARQ Related Parameters 140

Self-assessment on the Objectives 141End of Module 142





1 MIMO and Transmission Mode






1.1 Radio Resource Management

DL SchedulerDL Scheduler

UL SchedulerUL Scheduler

Cell Config

Power SettingRRM (Radio Resource Management Algorithm)

Radio Bearer configQoS parameter

RLC, CAC

UE feedbackUE radio conditionInterference Level

Scheduled UEsPRB Assignment per UE

MIMO SchemeMCS

One task of Dynamic Resource Allocation & Packet Scheduling (DRA&PS) Downlink Scheduler is to allocate radio resources to user and control plane packets. DRA involves several sub-tasks, including the selection of radio bearers whose packets are to be scheduled and managing the necessary resources (e.g. the power levels or the specific resource blocks used). PS typically takes into account the QoS requirements associated with the radio bearers, the channel quality information for UEs, buffer status, etc.

Other tasks of the DRA&PS are to define the algorithms put in place in order to efficiently manage the radio resources of the LTE system, and the MAC protocol used for that purpose.

The DRA&PS manages all the “MAC” part.

To schedule UEs every 1 ms, schedulers need inputs about:

the Radio Bearer QoS parameters (CallP, RLC, CAC),

the radio conditions of each UE (L1),

the configuration of the cell (Cell RRM and Power setting),

the interference level (ICIC).

From these inputs, schedulers (DL and UL) can allocate PRB, Transmission Mode (TM) and Modulation Coding Scheme (MCS) to UEs.






1.2 Transmission Evolution Evolution

In LA2.0, the following mixed modes were supported in TM4:

• TxDiv/2-layer CL-MIMO mixed mode • 1-layer CL-MIMO/2-layer CL-MIMO mixed mode • TxDiv/1-layer CL-MIMO/2-layer CL-MIMO mixed mode

In LA3.0, the “1-layer CL-MIMO/2-layer CL-MIMO mixed mode” is no longer supported, and, as explained below, the “TxDiv/2-layer CL-MIMO mixed mode” is achieved by disabling the 1-layer CL-MIMO (through proper configuration) in the basic LA3.0 TM4 mode “TxDiv/1-layer CL-MIMO/2-layer CL-MIMO mixed mode”.

Parameters dlSinrThresholdBetweenCLMimoTwoLayersAndTxDivand dlFullCLMimoMode are no longer used.






1.3 Transmission Mode Configuration

The following PDSCH transmission modes are defined:• TM2: the transmission scheme is TxDiv.• TM3: the transmission scheme is either 2-layer Open Loop MIMO (OL-MIMO) or TxDiv.• TM4: the transmission scheme is one of the following:

- 2-layer Closed-Loop MIMO (CL-MIMO).- 1-layer Closed-Loop MIMO.- Transmit Diversity (TxDiv).

Parameter transmissionMode

Object ENBEquipment/Enb/LteCell/LteCellFDD

Range & Unit Enumerate{tm1, tm2, tm3, tm4}

Class/Cat B--Cell / Optimization - Selection

Value tm4 (default)

It is well known that MIMO systems perform best in rich scattering environments. Choosing a specific transmissionMode is thus strongly influenced by the particular morphology of the cell. Transmit diversity has its value in a number of scenarios, including low SNR, low mobility (no time diversity), or for applications with low delay tolerance. Diversity schemes are also desirable for channels for which no uplink feedback signaling is available (e.g. Multimedia Broadcast/Multicast Services (MBMS).

Nevertheless, both tm3 (3), tm4 (4) perform TxDiv transmission for special propagation conditions, thus choosing tm2(2) should be a carefully thought decision based on specific cell morphology. Usually OL MIMO or CL MIMO (tm3, tm4) is applied in networks txDIV is used in case of low SNR or high speed , the condition of switching to txDiv depends on several parameter setting that is subjectible to optimization according to the site conditions For test purposes, it is possible to disable the second antenna of the eNodeB in the DL direction. This mode is called “fake SIMO”.






1.3.1 macMIMOModeDl Parameter

Parameter macMIMOModeDl

Object ENBEquipment/Enb/DedicatedConf/TrafficRadioBearerConf

ENBEquipment/Enb/DedicatedConf/SignalingRadioBearerConf

Range & Unit Enumerate{ mimoTwoLayersNotAllowed, mimoTwoLayersAllowed }

Class/Cat B--Cells-of-eNB / Fixed

Value

EngineeringRecommandation

When parameter macMIMOModeDl is set to “mimoTwoLayersNotAllowed”, the transmission is done using one of the two 1-layer schemes (TxDiv or CL-MIMO 1 layer).






1.3.1 macMIMOModeDl Parameter [cont.]

If macMIMOModeDl is set to “mimoTwoLayersNotAllowed”>> The transmission is done using TxDiv or CL-MIMO 1 layer.

If parameter transmissionMode is set to “tm1” or to “tm2”>> The parameter macMIMOModeDl is ignored.

TrafficRadioBearerConf: qCI TrafficRadioBearerConf: macMIMOModeDl

1 Not Significant

2- 9 mimoTwoLayersAllowed

SignalingRadioBearerConf::sRBIdentity SignalingRadioBearerConf::macMIMOModeDl

1 (SRB1) mimoTwoLayersNotAllowed

2 (SRB2) mimoTwoLayersNotAllowed






1.3.2 Rank And PMI Management

The rank indicator is a metric fed back by the UE. Rank Indicator indicates the number of freedom degrees measured by the receiver, which represents the maximum capacity of the TX/Rx channel in terms of independent streams.

Rank is equal to 1:Only one stream can be transmitted and Transmit Diversity is used.

Rank is equal to 2:Spatial Multiplexing becomes possible with a throughput higher than Transmit Diversity for high SINR values.

A forgetting factor is applied on the Rank provided by the UE in order to avoid too frequent changes of the

transmission scheme (TxDiv, 1 layer MIMO, 2 layer MIMO…).






1.4 TM3

In this mode, the transmission scheme used is either 2-layer OL-MIMO or TxDiv.

macMIMOModeDl is not set to “MimoTwoLayersNotAllowed”

The UE reports the CQI for its radio conditions and the Rank Indicator (RI) to indicate if it is able to distinguish the transmission of each antenna. From this feedback, the eNodeB can transmit 2 different transport blocks on each antenna using the same time-frequency resources. The pre-coding (blue box) matrix is pre-defined in Open-Loop MIMO. This is the way the data are mapped on each antenna.

The transmitter only knows the channel statistics of H but not its realization (hence “open-loop”).

The transmitter transmits equal power (P/M) from each antenna.

The receiver perfectly knows H.

Capacity grows linearly with the number of antennas.

The Open Loop MIMO/TxDiv selection is carried out based on the filtered rank, the

filtered effective SINR, an SINR threshold (ThSinrMimo) and a speed threshold

(ThSpeedMimo)






1.4 TM3 [cont.]

Parameter dlSinrThresholdBetweenOLMimoAndTxDiv

Object ENBEquipment/Enb/LteCell/TxDivOrMimoResources/MimoConfiguration/DownlinkMimo

Range & Unit Float[-10..30] step = 0.1 dB

Class/Cat B--Cell / Optimization - Selection

Value 15

When the RI is equal to 2, this parameter selects when the OL-MIMO is used depending on the radio

quality.

Higher values will reduce DL data rate otherwise achievable in the higher SINR regime.

Lower values would allow OL-MIMO too soon, resulting in H-ARQ retransmission rates and BLERshigher than achievable with Tx Diversity and consequently the use of an MCS with a lower DL data rate/throughput.

This parameter is a key RF optimization parameter.

Higher values will reduce DL data rate otherwise achievable in the higher SINR regime.

Lower values would allow OL MIMO too soon, resulting in HARQ retransmission rates and

BLERs higher than achievable with Tx diversity and hence the use of an MCS with a lower DL

data rate/throughput.

The current default value for this parameter is 15.0.






1.5 TM4

When in TM4, the UE also reports a codebook index to indicate the precoding matrix to use in case CL-MIMO is used

The mapping between the codebook and the precoding matrix is given in the table below:

In OL-MIMO, a fixed codebook is used:

A codebook contains a lookup table for coding and decoding. Each word or phrase has one or more strings which replace it. To decipher messages written in code, corresponding copies of the codebook must be available at either end.

The UE also reports the Precoding Matrix Indicator (PMI) for TM4

PMI indicates the codebook (pre-agreed parameters) the eNB should use for data transmission over multiple antennas based on the evaluation of the received reference signal.





1.5 TM4

1.5.1 Codebook Configuration

A set of boolean parameters is defined to allow or not the PMI and RI reporting to correspond to the precoding matrix they are associated:

Parameter

n2TxAntennaTm4OneLayerCodebook0




n2TxAntennaTm4TwoLayersCodebook1

n2TxAntennaTm4TwoLayersCodebook2

Object ENBEquipment/Enb/LteCell/TxDivOrMimoResources/MimoConfiguration/DownlinkMimo/CodebookSubsetRestriction

Range Boolean True/False

Cat B--Cell / Fixed

Value should be set to “True” in TM4 (transmissionMode = tm4) and to “False” in other transmission modes.

Engineering Recommendation: CodebookSubsetRestriction parameters

Parameters:

n2TxAntennaTm4OneLayerCodebook0,




n2TxAntennaTm4TwoLayersCodebook1 and

n2TxAntennaTm4TwoLayersCodebook2 should be set to “True” in TM4 (transmissionMode = tm4) and to

“False” in other transmission modes.





1.5.1 Codebook Configuration

1.5.1.1 dlMIMODefaultCodeBook

The default codebook used by the downlink scheduler before the UE reports the first PMI is configured by parameter dlMIMODefaultCodeBook.

Parameter dlMIMODefaultCodeBook


Range & Unit Enumerate{1LayerCodebook0, 1LayerCodebook1, 1LayerCodebook2,1LayerCodebook3, 2LayersCodebook1, 2LayersCodebook2}

Class/Cat B--Cell / Fixed

Value TM4 dlFullCLMimoMode: Enabled 1LayerCodebook0

TM4 dlFullCLMimoMode: Disabled 2LayersCodebook1





1.5 TM4

1.5.2 Basic LA3.0 TM4 Mixed Mode

In LA3.0, the “1-layer CL-MIMO/2-layer CL-MIMO mixed mode” is no longer supported,“TxDiv/2-layer CL-MIMO mixed mode” is achieved by disabling the 1-layer CL-MIMO proper configuration) in the basic LA3.0 TM4 mode “TxDiv/1-layer CL-MIMO/2-layer CL-MIMO mixed mode”.

macMIMOModeDl: “MimoTwoLayersNotAllowedΛ

reported (and filtered) rank is 1

The downlink transmission scheme configured at cell-level will be either TxDiv or 1-layer CL-MIMO for all the bearers

established in the cell





1.5 TM4

1.5.2 Basic LA3.0 TM4 Mixed Mode [cont.]

If parameter dlSinrThresholdBetweenCLMimoOneLayerAndTxDiv is set equal to

dlSinrThresholdBetweenCLMimoTwoLayersAndOneLayer the downlink

transmission scheme configured at cell level will be either TxDiv or 2-layer CLMIMO

(i.e. CL-MIMO 1 layer is disabled), the switching threshold being

dlSinrThresholdBetweenCLMimoOneLayerAndTxDiv =

dlSinrThresholdBetweenCLMimoTwoLayersAndOneLayer in this case.

If, besides, the reported (and filtered) rank is 1, the downlink transmission scheme

will just be TxDiv.

Also, if parameter macMIMOModeDl is set to “MimoTwoLayersNotAllowed”, the

downlink transmission scheme configured at bearer-type level will be TxDiv for all

the cells hosted by the eNB.





1.5.2 Basic LA3.0 TM4 Mixed Mode

1.5.2.1 TM4 mixed Mode CL-MIMO Parameters

Parameter dlSinrThresholdBetweenCLMimoTwoLayersAndOneLayer

dlSinrThresholdBetweenCLMimoOneLayerAndTxDiv


Range & Unit

Float [-10..30] step = 0.1 dB


Value 12.0 -10

dlSinrThresholdBetweenCLMimoTwoLayersAndOneLayer

This parameter is a key RF optimization parameter. Higher values will reduce downlink 2 layers data rate

too soon, resulting in HARQ retransmission rates and BLERs higher than achievable with 1 layer and hence

the use of an MCS with a lower downlink data rate/throughput.

The current default value for this parameter is 12.0.





2 Measurement Management





2 Measurement Management

2.1 Measurement Management

The UE measures the Reference Signal (RS) It is transmitted by the 2 (4) antennas on

a predefined pattern over the entire wideband

A UE performs aperiodic CQI, PMI and RI reporting using the PUSCH channel.

- The CQI, PMI and RI reports follow a fixed 20ms pattern aligned with the uplink

semistatic scheduler >> the overhead is big:

- Nearly 10% for 8 UEs and 20% for 16 UEs with two HARQ retransmissions.

In LA3.0 periodic CQI is supported over PUCCH to provide low overhead channel

feedback.

PUSCH

CQI, PMI and RI

20ms

The CQI, PMI and RI reports follow a fixed 20ms pattern aligned with the UL semi-static VoIP scheduler.






2.1.1 PUSCH Configuration For Aperiodic CQI

UE can be requested to send PUSCH aperiodic CQI/PMI reports on top of the PUCCH periodic reports. A UE performs PUSCH (aperiodic) CQI, PMI and RI reporting upon reception of DCI format 0 with the CQI request field set to 1.Parameter nomPdschRsEpreOffset configures the nominal measurement offset between the PDSCH RE power and RS RE power that the UE should assume when computing CQI. It is divided by two at RRC prior to transmission to the UE.

Parameter nomPdschRsEpreOffsetObject ENBEquipment/Enb/LteCell/CellL2DLConf

Range & Unit Integer[-2..12] step = 2 dB


Value 0






2.1.1 PUSCH Configuration For Aperiodic CQI [cont.]

The CQI report mode is configured at RRC setup. Parameter cqiReportingModeAperiodic configures the mode used for Aperiodic CQI report.

Parameter cqiReportingModeAperiodicObject ENBEquipment/Enb/LteCell/CellL1ULConf/CellL1ULConfFDD

Range & Unit

Enumerate {disabled, rm30, rm31, rm12}


Value TM2 rm30TM3 rm30TM4 rm31,rm12

This parameter must be set in accordance to the transmission mode configured by

parameter transmissionMode.

Values “rm30” and “rm31” correspond to reported modes 3-0 and 3-1 respectively.

If the parameter is set to “disabled”, the uplink scheduler does not send grants for CQI reports.

The mapping transmissionMode/ cqiReportingModeAperiodic is as follows:

Tm2/ rm30

Tm3/ rm30

Tm4/ rm31 Or rm12






2.1.2 CQI (Channel Quality Indicator)

There are 3 CQI/RI/PMI report formats:

Mode 3-0The UE reports a wideband CQI value.The UE also reports one subband CQI value for each subband.Both the wideband and subband CQI represent channel quality for the first codeword,

even when RI>1.

Mode 3-1A single precoding matrix is reported. This matrix is selected from the codebook

Subset assuming transmission on.The UE reports one subband CQI value per codeword for each subband.The UE reports a wideband CQI value per codeword

The number of RB per sub-band depends on the bandwidth.

With 5 MHz, there are 7 sub-bands and 4 RB per sub-band. Except for the last sub-band (only one RB)

With 10 MHz, there are 9 sub-bands and 6 RB per sub-band. Except for the last sub-band (only 2 RB)

With 20 MHz, there are 13 sub-bands and 8 RB per sub-band. Except for the last sub-band (only 4 RB)






2.1.2.1 Sub-Band CQI

The Wideband CQI is coded on 4 bitsSubband CQI value for each codeword are encoded differentially with respect to their respective wideband CQI using 2-bits as defined by:

Subband differential CQI offset level = subband CQI index – wideband CQI index.

The mapping from the 2-bit subband differential CQI value to the offset level is shown here:

Each Sub-Band CQI represents the CQI for several RB (depends on the bandwidth)

Subband DifferentialCQI Value

Offset level

0 0

1 1

2 2

3 -1






Subband Index With 5 Mhz

Sub-bandindex

RBs where CQI ismeasured

Updated CQI for codeword 1

SB0 0 to 3 CQI1,0; CQI1,1; CQI1,2; CQI1,3






SB6 24 CQI1,24





2.1.2.1 Subband CQI

Subband index with 10 Mhz

Sub-bandindex



SB0 0 to 5 CQI1,0; CQI1,1; CQI1,2; CQI1,3; CQI1,4; CQI1,5

SB1 6 to 11 CQI1,6; CQI1,7 ; CQI1,8; CQI1,9; CQI1,10; CQI1,11

SB2 12 to 17 CQI1,12; CQI1,13; CQI1,14; CQI1,15 ; CQI1,16; CQI1,17






SB8 48 and 49 CQI1,48; CQI1,49






Subband index with 20 Mhz

Sub-bandindex



SB0 0 to 7 CQI1,0 to CQI1,7

SB1 8 to 15 CQI1,8 to CQI1,15

SB2 16 to 23 CQI1,16 to CQI1,23

SB3 24 to 31 CQI1,24 to CQI1,31

SB4 32 to 39 CQI1,32 to CQI1,39

SB5 40 to 47 CQI1,40 to CQI1,47

SB6 48 to 55 CQI1,48 to CQI1,55

SB7 56 to 63 CQI1,56 to CQI1,63

SB8 64 to 71 CQI1,64 to CQI1,71

SB9 72 to 79 CQI1,72 to CQI1,79

SB10 80 to 87 CQI1,80 to CQI1,87

SB11 88 to 95 CQI1,88 to CQI1,95

SB12 96 to 99 CQI1,96 to CQI1,99






2.1.2.2 Wide Band SINR

The Wide Band CQI for both codewords is converted into an internal SINR through a table configured by parameter cQIToSINRLookUpTable.

This conversion takes into account the UE speed estimated by L1.

Parameter cQIToSINRLookUpTable

Object ENBEquipment/Enb/EnbRadioConf

Range & Unit List of 15 Float values [-10..30] step = 0.25 dB

Class/Cat B--Modems+Cells-of-eNB / Fixed

Value [-6.00, -4.00, -2.75, -0.75, 1.25, 2.75, 5.00, 6.75, 8.50, 10.75, 12.50, 14.50, 16.25, 17.75, 20.00]

This table uses the 4 bits CQI as an entry, and reports the equivalent SINR.

In the 1/1 reuse pattern, all the RBs are potentially usable by the UE, in this case, SINR1,WB and SINR2,WB

are given by the CQI-to-SINR lookup table (configured by parameter cQIToSINRLookUpTable) based on the

UE reported Wide Band CQI;

SINR1,WB = cQIToSINRLookUpTable[Wide Band CQI CW1]

SINR2,WB = cQIToSINRLookUpTable[Wide Band CQI CW2]

In case the Rank indicates 1 codeword, the UE reports a Wide Band CQI

CW2 equal to 0 and the content of the SINR2,WB is set to -20dB.






2.1.3 PUSCH Configuration For Aperiodic CQI

In LA3.0, subband CQI reports, if needed, are provided via PUSCH aperiodic CQI reports.Only modes 1-0 and 1-1 are supported in LA3.0:

Mode 1-0The UE reports a wideband CQI value, representing channel quality for the first

Codeword (even when when rank =2).

Mode 1-1A single PMI is reported. This matrix is selected from the codebook subset assuming

transmission on set S subbands.The UE reports a 4-bit wideband absolute CQI value CQI1,WB for the first codeword,

calculated assuming the use of a single PMI in all subbands and transmission on all subbands.

When rank = 2, the UE also reports a 3-bit wideband differential CQI value for the second codeword.

PMI Feedback Type

No PMI Single PMI

PUCCH

CQI

Feedback Type

Wideband(wideband CQI)

Mode 1-0 Mode 1-1

UE Selected(subband CQI)

Mode 2-0 Mode 2-1

The wideband absolute CQI value CQI2,WB for the second codeword is obtained as CQI2,WB = CQI1,WB

CQI_Offset where CQI1,WB is derived from the differential CQI value as follow:

3-bit differential CQI value for second codeword// CQI_Offset

0// 0

1//1

2//2

3//3

4 //- 4

5 //- 3

6 -/ -2

7 // -1





3 Schedulers





3 Schedulers

3.1 Dynamic Resource Allocation & Packet Scheduling

UL Scheduler

DL SchedulerU

L/DL Intra eN

B schedulers info

RRM ICIC

RRM CAC

Power Setting

CallP

Cell/RRM

L1

RLC

Frequencies

Admited UEs

Phy ChannelPower

QoS parameters

Common Channels Config

HARQ Status, CQI,

RI &PMI

RLC Queues Status

Scheduled UEs PRB Assignment per UE

TxDiv/SIMO/MIMO schemeMCS

In order to efficiently utilize the physical layer resources, a scheduling function is

used in the MAC layer of the eNB.

Different schedulers operate for the uplink and the downlink. The uplink and downlink schedulers assign

resources based on

• The QoS requirements of the UE’s bearers requirements.

• The radio conditions of the UEs identified through measurements made at the eNB (in the uplink) or

reported by the UE (in the downlink).

• The amount of data to transmit per UE and per bearer.

Resource assignment consists of Physical Resource Block (PRB) and Modulation Coding Scheme (MCS).





3 Schedulers

3.1 Dynamic Resource Allocation & Packet Scheduling [cont.]

3GPP definition of DRA & PS:

The task of dynamic resource allocation (DRA) or packet scheduling (PS) is to allocate and de-allocate resources (including buffer and processing resources and resource blocks (i.e. chunks)) to user and control plane packets.

DRA involves several sub-tasks, including the selection of radio bearers whose packets are to be scheduled and managing the necessary resources (e.g. the power levels or the specific resource blocks used).

DRA & PS Location





3.1 Dynamic Resource Allocation & Packet Scheduling

3.1.1 Schedulers Principles

The Static Scheduler: Which assigns a fixed amount of Transport Blocks for the PBCH and the synchronization signals. Those resources are permanently allocated.

The Semi-static Scheduler: Which assigns PDSCH resources for PCCH and CCCH and the D-BCH. The semi-static scheduler also assigns a regular set of Transport Blocks for all established VoIP bearers.

The Dynamic Scheduler: Which assigns Transport Blocks as well as PDCCH and PDSCH resources for DCCH & DTCH over the DL-SCH Transport Channels. The dynamic scheduler is also in charge of sending the MAC Control Timing Advance control messages in order to keep the UE in the connected mode, synchronized with the network.

UL and DL schedulers are located in the eNodeB (in the CEM boards).

They handle the allocation of the radio resources to all the DL and UL channels taking into account:

The link adaptation (MCS selection)

The measurement reporting configuration

The Transmission mode selection

The H-ARQ retransmission

The resource allocation

Inter-Cell Interference Coordination






3.1.1.1 TimeFrequencyResBlockOccupancy Matrix

This matrix is used by the static and semi-static scheduler to flag the RBs which are pre-booked for their needs.

This matrix has a 20ms depth20 sub-frames or 2 radio frames

This bitmap is 25-RB long in 5MHz bandwidth, and 50-RB long in 10MHz bandwidth

TimeFrequencyResBlockOccupancy[t][rb] are flagged with for example:

FREE

USED_D_BCH

USED_PCCH

RESERVED_SRB_TA

USED_VOIP





DL Scheduling StageDL Scheduling StageDL Prebooking StageDL Prebooking Stage


3.1.1.2 Pre-booking and Scheduling stages

The input is the :TimeFrequencyResBlocOccupancymatrixavailable PDSCH resources for L2

Static scheduler prebooking

Semi static scheduler prebooking

The Output is the TimeFrequencyResBlocOccupancy matrix with blocks reserved for static and semi static schedulers

The output is teh interface to L1 for PDSCH and PDCCH

Dynamic scheduler

Semi static scheduler scheduling stage

static scheduler scheduling stage

The input is the :TimeFrequencyResBlocOccupancy with blocks reserved for static and semi static schedulers

20 ms

1ms

The downlink scheduler is composed of 2 main algorithms:

• A prebooking stage which reserves resources for the static and semi-static

schedulers.

• A scheduling stage which assigns the resources for effective traffic.

The LTE DL scheduler is composed of 2 main algorithms:

A pre-booking stage which reserve resources over the PDSCH for the static and semi-static schedulers.

A scheduling stage which assign the resources over the PDSCH for effective traffic.

The input of the scheduler is the TimeFrequencyResBlocOccupancy matrix further described in §5.1.3.4.

The output is the interface to L1 DL for both PDSCH and PDCCH further described in [A1].

The following diagram shows the functional blocks involved in the DL scheduler to allocate the TimeFrequencyResBlocOccupancy matrix and populate the interface to the L1 DL:





LCPDL

PDB

BLER

SiNRLCID

3 Schedulers

3.2 Downlink Scheduler

The main role of the downlink scheduler is to efficiently manage and allocate the available downlink resources to the UEs having contexts in the DLRRCConnectedUserList.

The downlink UE context contains the UE category, the UE DL AMBR and the UEbearers list UebearerList, and the UE MG status.

DL Scheduler

Tx Mode

MgActive

InitialMCS

UE Categories

UE DL AMBR

UE Bearer list

UE MG status

MgPeriod

HARQ (MaxTx,ProcessTimer

MgOffset

QoSParametersVoIp,GBR,

MBR..

PDB

The downlink UE context contains the UE category, the UE DL AMBR and the UE bearers list UebearerList,

and the UE MG status. The latter consists of the following 3 parameters:

• MgActive: Flag indicating if MG is active for the UE.

• MgPeriod: Measurement Gap Repetition Period, derived from parameter measurementGapsPattern.

• MgOffset: MG Offset of the UE.

In LA3.0 the maximum number of users in the RRCConnectedUserList in LA3.0 cannot

exceed 167





3 Schedulers

3.2 Downlink Scheduler [cont.]

In LA3.0, a maximum of 10 bearers can be established in the UEBearerList for an active UE (UE in RRC connected state and monitoring PDCCH).

The maximum number of data radio bearers that can be supported by a given UE is determined by the combination of 2 factors:

1. Feature Group Indicator bit 7 from the UE Capabilities2. Feature Group Indicator bit 20 from the UE Capabilities

The maximum Radio Bearer combinations depending on both bit 7 and bit 20 of IE feature GroupIndicators can be summarized as follows:

Bit 7

Bit 20

UE Support

SRB1 SRB2AM UM

DRB1 DRB2 DRB3 DRB4 DRB5 DRB6 DRB7 DRB8 DRB1 DRB2 DRB3

0 0 X X X X X X

0 1 X X X X X X X X X X

1 0 X X X X X X X

1 1X X X X X X X X X X

X X X X X X X X X X

1. Feature Group Indicator bit 7 from the UE Capabilities:

bit 7 of IEfeatureGroupIndicators = 0 indicates that RLC UM mode is not supported by the UE.

2. Feature Group Indicator bit 20 from the UE Capabilities:

bit 20 of IE featureGroupIndicators provides information on the support of Radio Bearer combinations. It

is checked together with bit 7.

If IE featureGroupIndicators is not sent by the UE, the eNB assumes that all the radio bearer combinations are supported (equivalent to both bit 7 and bit 20 in IE featureGroupIndicators set to 1).

In LA3.0, no more than one VoIP bearer per UE is supported. If more than 1 UM is

supported, then VoIP bearer checking has to be performed to ensure this restriction.

Also, requested combinations not supported by the UE are rejected.






3.2.1 Signaling Radio Bearer Parameter

Two instances of object SignalingRadioBearerConf need to be generated (one

for SRB1 and another one for SRB 2).

Each instance is identified sRBIdentity

Parameter signalingRadioBearerConfName

Object ENBEquipment/Enb/DedicatedConf/SignalingRadioBearerConf

Range & Unit String of up to 64 characters

Class/Cat C--Immediate-propagation / Fixed

Value sRBIdentity1 SRB1

sRBIdentity2 SRB2






3.2.2 DL Static Scheduler

The static scheduler is in charge of scheduling all the logical channels which have stringent timing constraints and regular usage of the resourceIt prebooks resources in the TimeFrequencyResBlockOccupancy matrix which are always used and thus can never be retrieved by the Dynamic SchedulerIt manages:

The BCCH information that goes over the BCH channel, i.e the MIB in the PBCH.The primary and secondary synchronization signals.

RE allocated by semi static schedulers for PBCH

Frequency

RB 1st Slot RB 2nd Slot

The static scheduler allocates the following resources for PBCH:

RBs 9-15 (7 RBs) of sub-frame 0, in a 5MHz bandwidth system.

RBs 22-27 (6 RBs) of sub-frame 0, in a 10MHz bandwidth system.

The static scheduler is configured at cell setup, and does only change with a cell restart.






3.2.3 DL Semi-Static Scheduler

In DL, the semi-static scheduler is in charge of scheduling all the logical channels which have stringent timing constraints and non-regular usage of the resource.

The downlink semi-static scheduler assigns resources to:PCCH, CCCH (SRB0), VoIP DTCH (GBR-1 bearer) logical channels and DBCH,RACH message 2.

D-BCH:Yes: Prebooked resources will be usedCCCH:Yes: Prebooked resources will be usedPCCH: Yes:Prebooked resources will be usedVoIP DTCH: No:Prebooked resources will be freedRACH message 2 : Prebooked resources will be freed

Prebooked resources will be freed

Semis static scheduler

Dynamic scheduler

1ms

1ms

D-BCH refers to the part of the BCCH logical channel that is

sent over the DL-SCH channel (SIBs), as opposed to the BCH which is sent over the PBCH (MIB).

There is no pre-booking of SRB/TA resources at 1 In order to meet the timing constraints, the semi-static

scheduler prebooks resources in the TimeFrequencyResBlocOccupancy matrix. As opposed to the static

scheduler, and due to the non-regular throughput required by this type of information, the

prebooked resources are not always used. When not used, the resources are freed

by the semi-static scheduler and retrieved by the dynamic scheduler.






3.2.3.1 D-BCH Scheduling

D-BCH carries System Information Blocks (SIBs).In LA3.0, SIB1, SIB2, SIB3, SIB4, SIB5, SIB6, SIB7 and SIB8 are supported.A SIB Is considered active when its associated parameters are set to “TRUE”

** Large SI-messages may be split into smaller messages for transmission, especially

if they require more RBs than the number of available RBs.

SIB6/SIB7 and SIB8 are mutually exclusive- that is, if one is present, the other cannot be transmitted.

Operators are not expected to support mobility to UTRAN/GERAN and to HRPD from an eNB






SIB1 Scheduling

D-BCH carries System Information Blocks (SIBs).In LA3.0, SIB1, SIB2, SIB3, SIB4, SIB5, SIB6, SIB7 and SIB8 are supported.SIB1 is always scheduled in subframe 5 of radio frames with system frame number (SFN)mod 8=0It therfore has a fixed periodicity of 80 ms or 8 radio frames (rf8)It is also repeated in subframe 5 of every even numbered SFN.

80ms (rf8) periodicity

10ms

SIB 1 scheduled inSFN=8nSubframe 5

SIB 1 scheduled inSFN=8n+8Subframe 5

10ms

Repeated Transmissions

SFN

** Large SI-messages may be split into smaller messages for transmission, especially

if they require more RBs than the number of available RBs.

o transmission can occur at any subframe except MBSFN subframes (not supported in LA3.0) and SIB1

subframes.






SIB2,…SIB8 Scheduling

SIB 2 SIB 3 SIB 4 SIB 5 SIB 6 SIB 7 SIB 8

SIB2 through SIB8 are scheduled according to a scheduling class (1, 2 or 3) to which each SIB is assigned.

Each scheduling class is defined with a periodicity and target MCS:periodicity: 80, 160, 320, 640, 1280, 2560, and 5120 ms are the possible values.SIBs of the same scheduling class are mapped to the same SI message for

transmission. 6 SIBs could be transmitted simultaneously (LA3.0)Assignement of system information (SI) messages into 3 scheduling priorities to

reduce Downlink Scheduler complexity.Multiple SIBs can be grouped in the same SI-messageThe configuration of the MCS used for transmission of SIBs optimizes the physical

link usage.

The parameters sibClass(1,2,3)TargetMCS configure the index of the most robust MCS that can be used for SIB2 – SIB8 messages.

The MCS used is determined by a specific algorithm and selected from the set [sib1TargetMCS +6, 9] for SIB1 and [sibClass(1,2,3)TargetMCS, 9] for SIB2, through SIB8 according to the scheduling class (1,2,or 3) assigned to the SIB.

Note that the MCS range never goes outside the range [0, 9] for QPSK is mandatory for the transmission of SI messages.






sibClass1,2,3 Target MCS Parameters

Parameter sibClass1TargetMCS sibClass1TargetMCS sibClass1TargetMCSObject ENBEquipment/Enb/LteCell/SysInfoConf

Range & Unit Integer [0..9]Class/Cat C--Immediate-propagation / Fixed

Value 0 0 0

SI messages must use QPSK (MCS) for transmission. Therfore, only MCS 0 through 9 are allowed.The target MCS indicates the most robust MCS for an SI message. The lower the target MCS, the most robust it is. The target MCS is configurable for SIB1 and for SIB scheduling class1,2 and 3.

Parameter sib1TargetMCSObject ENBEquipment/Enb/LteCell/SysInfoConf

Range & Unit Integer [0..9]Class/Cat C--Immediate-propagation / Fixed

Value 2

The parameters sibClass(1,2,3)TargetMCS configure the index of the most robust MCS that can be used for SIB2 – SIB8 messages.

The MCS used is determined by a specific algorithm and selected from the set [sib1TargetMCS +6, 9] for SIB1 and [sibClass(1,2,3)TargetMCS, 9] for SIB2, through SIB8 according to the scheduling class (1,2,or 3) assigned to the SIB.

Note that the MCS range never goes outside the range [0, 9] for QPSK is mandatory for the transmission of SI messages.

Ideally, the scheduler uses the configured target MCS. However, if there are not enough resources available that are needed for target MCS usage, this requires the scheduler to dynamically select a higher MCS.

A higher MCS uses less resources, but it is also less robust so may require scheduled retransmissions of the SI message since the first transmission may not be error-free.






SIB Configuration: Data Model: Periodicity

Up to 3 scheduling classes are defined, so SIBs can be groubed into 1,2 or 3 different

scheduling classes, resulting in larger System Information messages but broadcasted less

frequently to reduce bandwitdth and scheduling complexity.

SIBs grouped in the same scheduling class are grouped in the same System information

message. Lte Cell

SysInfoConf

sib2SchedulingClass

sib3SchedulingClass

sib4SchedulingClass

sib5SchedulingClass

sib6SchedulingClass

sib7SchedulingClass

sib8SchedulingClass

sib2ClassTargetPeriodicity


Value123

Value

Rf8, rf16,Rf32, rf64,

rf128, rf256,rf512


sibClass1TargetPeriodicity =<sibClass2TargetPeriodicity =<sibClass3TargetPeriodicity






SIB Configuration: Data Model: Target MCS

Lte Cell

SysInfoConf

sib2SchedulingClass

sib3SchedulingClass

sib4SchedulingClass

sib5SchedulingClass

sib6SchedulingClass

sib7SchedulingClass

sib8SchedulingClass

sib2ClassTargetMCS

sib3ClassTargetMCS

Value123

Value

0,1,2,3,4,5,6,7,8,9

sib1ClassTargetMCS

Sib1 TargetMCS[ALU Value = 2]

Each scheduling class should differ by the periodicity, the Target MCS, or both (this will be a WPS check in LA4.0)

sibClass1TargetPeriodicity =<sibClass2TargetPeriodicity =<sibClass3TargetPeriodicity

** Large SI-messages may be split into smaller messages for transmission, especially if they require more

RBs than the number of available RBs.

Each scheduling class should differ by the periodicity, the target MCS or both (this will be a WPS check in

LA4.0)






ALU LA3.0 Configuration Values

Shorter periodicities use more downlink radio bandwidth and should be avoided for the larger SIBs

Grouped in the same System Information message

Grouped in the same System Information message

* Note that scheduling Class 3 is not used in recommended ALU configuration






SI-Messages Scheduling

SIB 2 and upwards are carried in System Information Message (SI-Message), which contain one or several SIBs and are broadcast within recurring periods called SI-Windows.

The duration of the SI-window is fixed to 20ms in the ALU implementation (2 consecutive 10 ms frames) for all SI-Messages, and is broadcast in SIB1.

The first SI-Message to be scheduled (SI-Message #0) must contain SIB2 in the first position, and an SI-Message may only contain SIBs that have the same periodicity.

SI-window SI-window

Radio FrameWith SFN=0




SIB1: SI-message 0 SI-message 1:

SI-message Retransmissions

SI-Windows of different SI-Messages do not overlap, in other words only one SI-Message is broadcast and retransmitted within subframe of an SI-window.






SI-Message Scheduling

SI-Message 0:SIBs 2,3

Periodicity: rf64

SI-Message 1:SIBs 4,5,6,7

Periodicity: rf64

SI-Message 0:SIBs 2,3

Periodicity: rf64

SI-Message 0:SIBs 4,5,6,7,

Periodicity: rf64

64 radio Frames20 msSI-Window

16 radio frames

m m+1 n n+1 16m 16m+1 64n 64n+1

SI-Message scheduling example based on ALU recommended valuesApplicable to SIB2…8






SI-Message Scheduling

The DL semi static semi static scheduler computes the number of RBs needed for SI-message transmission, based on the size of the SI-message and Target MCS.

If an SI-message requires more RB than the number of available RBs, then it is split into smaller messages using any free RB which where allocated to, but not used by other SI-messages

Semi Static Scheduler:

Number of available RBs=Max Number of RB (BW dep)-

numberRBnotforSib

Number of available RBs (>=<)(RBs needed for SI-message transmission)

If: RBs number required for SI-Message transmission > Number of available RB, SI-message issplitt into smaller messages.

BW 5Mhz 10Mhz 20Mhz

Max Nb RBs 25 50 100

• An SI-message cannot have a size greter than 2216 bits due to a 3GPP limitation.

If an SI-message is above this maximum size, then it is split into 2 or more SI-message that are smaller than the original one.

If splitting SI-message # 0 containing SIB2, it is important to note that SIB 2 cannot be removed out of SI-message #0.

• The DL semi static semi static scheduler computes the number of RBs needed for SI-message transmission, based on the size of the SI-message and Target MCS, it is then, compared to the number of available RBs, which is determined by the parameter SysInfoConf::numberRBnotForSIB and the max number of RBsdetermined by system bandwitdh, fixed as follow:

• If after splitting still not enough RBs are available, the MCS is increased by 3 and retransmission is added (to account for the possible increase in BLER due to the higher MCS). Increasing the MCS reduces the number of RBs needed to be allocated







numberRBnotforSIB Parameter

A large SI message containing at least two SIBs may be split into smaller SImessages,

where each SIB from the large SI-message is allocated to one of the smaller SI-messages.

An SI-message may be split for the following reasons:

If the size of the SI-message is greater than 2216 bitsIf the SI-message requires more RBs than the calculated ‘number of RBs available for SIBs’.

Parameter numberRBnotForSIB

Object ENBEquipment/Enb/LteCell/SysInfoConf

Value 5Mhz& 10 Mhz& 20Mhz 8

After SI-messages have been splitted (if needed), if the number of RBs to allocate for an SI-message is still

greater than the ‘number of RBs available for SIBs’, the MCS is increased by 3, and a retransmission is

scheduled (to account for the possible increase in BLER due to the higher MCS), until the re-calculated

number of RBs to allocate is less than or equal to the ‘number of RBs available for SIBs’.






3.2.3.2 PCCH Scheduling

In each frame, the semi-static scheduler prebooks a set of contiguous RBs for PCCH. The resources are prebooked in subframe 9. The number of prebooked RBs depends on the MCS and is limited to 6.

SF#:1 2 3 4 5 6 7 8 9 10 1 2 3 4 5 6 7 8 9 10

BW

Up to 6 RB





3.2.3.2 PCCH Scheduling

pagingForceMCSmin Parameter

Parameter pagingForceMCSmin configures the index of the most robust MCS that can be used for SI messages:

The MCS used is determined by a specific algorithm and selected from the set:• [0 , 9] for all SIB messages if parameter pagingForceMCSmin is set to -1.• [pagingForceMCSmin, 9] if parameter pagingForceMCSmin is not set to -1.

Parameter pagingForceMCSmin

Object ENBEquipment/Enb/LteCell/CellL2DLConf

Range & Unit Integer [-1..9]


Value - 1

Note that regardless of the value of parameter pagingForceMCSmin, the MCS range never goes outside the

range [0, 9] for QPSK is mandatory for the transmission of paging messages.






3.2.4 DL Dynamic Scheduler

The input for the dynamic scheduler is on a per sub-frame:The RB allocation of the semi-static scheduler, which are not usable by the

dynamic scheduler.A number of remaining CCE resources to share among

The Dynamic scheduler can be decomposed into 3 sequential functions:

Measurement processing and transmission mode selection, updated every TTI and used in the 2 following functions.

Initial transmissions processing functions, allocating the remaining resources to new transmissions.

HARQ retransmissions processing functions, managing in priority the users with HARQ retransmissions.

1

2

3

users.The dynamic scheduler is in charge of scheduling all the logical channels which have non-stringent

timing constraints and non-regular usage of the resource.

The downlink dynamic scheduler assigns resources to:

• Non-VoIP DTCH (GBR2, GBR3, GBR4 and non-GBRs) and DCCH (SRB1 and SRB2) logical channels.• Timing Advance control messages.






3.2.5 DL Fairness Factor

Parameter alphaFairnessFactor tunes the alpha fairness factor (thus the behavior)of the scheduler:

• alphaFairnessFactor = 0 yields a maximum C/I scheduler. • alphaFairnessFactor = 1 yields a fair scheduler. • alphaFairnessFactor = 2 yields an increased fairness scheduler.

This parameter provides flexibility as to the choice of scheduler behavior, allowing The operator to choose the scheduler behavior they wants for their network.

Parameter alphaFairnessFactor

Object ENBEquipment/Enb/LteCell/CellL2DLConf

Range & Unit Float [0..2] step=0.5

Class/Cat B--Cell / O.D.

Value (ALU default: 1.0)

The initial transmission scheduling algorithm is the so-called Alpha Fairness

scheduler, which is a generalization, by means of parameter alphaFairnessFactor, of the widely used

Proportional Fair scheduler.

• alphaFairnessFactor = 0 yields a maximum C/I scheduler. The scheduler provides more resources to UEs in

better conditions. The better the radio conditions of the UE, the more resources (and hence the higher the

data rate) it gets.

• alphaFairnessFactor = 1 yields a fair scheduler. The scheduler attempts to

provide the same number of RBs to all the UEs (despite their different

conditions).

• alphaFairnessFactor = 2 yields an increased fairness scheduler. The scheduler attempts to allocate the

resources in such a way that all the UEs eventually get the same data rate (which is not the case of the fair

scheduler since different radio conditions result in different data rates even when the

number of resources is the same, hence the increased fairness of the scheduler, as compared to the

“regular” fair scheduler).

This parameter provides flexibility as to the choice of scheduler behavior, allowing The operator to choose

the scheduler behavior they wants for their network.






3.2.6 Resource Block Group Allocation

The downlink scheduler uses a bitmap of Resource Blocks (RB), PhyResBlocOccupancy. In the time domain, at each subframe (i.e. every 1 ms), the number of RBs available in

the PhyResBlocOccupancy bitmap is updated.

This procedure consists in allocating the Groups of Resource Blocks remaining after the semi-static scheduling and HARQ allocation stages.

These RBGs are provided by PhyResBlocOccupancy.The procedure allocates an RBG to one bearer chosen from the list of eligible bearers,

according to their respective allocation metric.

RBG Size (P) System BandwidthNRB

DL

1 ≤ 10

2 11- 26

3 27- 63

4 64- 110

When a bearer is selected for transmission, the scheduler checks whether there are enough PDCCH

resources available for the grant. If there are not enough resources available for the grant, the bearer is

not scheduled.





3 Schedulers

3.3 UL Scheduler

The main role of the uplink scheduler is to efficiently manage and allocate the available uplink resources to the UEs having contexts in the UL

RRCConnectedUserList.Scheduler selects bandwidth, modulation, use of MU-MIMO, and PC parametersPRBs assigned for a particular UE must be contiguous in the uplink (SC-FDMA)

UE AUE BUE C

TimeFr

eque

ncy

UL UE Context:• UE category• UE UL AMBR• UebearerList• UE MG status

UE AUE A

The UL UE context contains the UE category, the UE UL AMBR, UebearerList and

the UE MG status. The latter consists of the following 3 parameters:

MgActive: Flag indicating if MG is active for the UE.

MgPeriod: MG Repetition Period, derived from parametermeasurementGapsPattern.

MgOffset: MG Offset of the UE.

In the UEBearerList, a bearer context is identified by the Logical Channel Identifier (LCID) of the logical

channel it is mapped onto. The bearer context also contains, among other information:

• The VoIP flag (derived by CallP from QoS received from the MME over the S1-C).

• The UL GBR (derived by CallP from QoS received from the MME over the S1-C).





3 Schedulers

3.3 UL Scheduler [cont.]

The uplink scheduler consists of several functional parts:

• The Static Scheduler: assigns resources to RACH message 1 and RACH message 3.• The Dynamic Scheduler: assigns resources to non VoIP DTCH (GBR2, GBR3, GBR4 and non-GBRs) and DCCH (SRB1 and SRB2).• The MIMO Scheduler is part of the Dynamic Scheduler and is responsible for scheduling multiple UEs in the same time-frequency resources.

The PRBs are assigned every subframe in the following order:1. Static grants.2. Dynamic grants.





3.3 UL Scheduler

3.3.1 UL Static Scheduler

The uplink static scheduler assigns resources to RACH message 1 and RACH message 3.The RACH preamble (RACH message 1) is generated by the MAC layer on RACH and transmitted on PRACHRACH message 3 is transmitted 6 ms after RACH message 2.

RA•CH •U•L•-•SCH

•P•U•SCH •P•U•CCHPRACH

UL Transport Ch

UL Physical Ch

Random Access Preamble

Random Access Response

Scheduled Transmission

Contention Resolution

1

4

3

2

6ms





3.3 UL Scheduler

3.3.1 UL Static Scheduler [cont.]

RACH message 3 is scheduled as follows:RACH message 3 is transmitted 6 ms after RACH message 2.The starting PRB index for the transmission of RACH Message 3 is configured by parameter rACHMessage3StartingPRBIndex.The number of PRBs used for the transmission of RACH Message 3 is configured by parameter rACHMessage3NumberOfPRBs.The index of the MCS used for the transmission of RACH Message 3 is configured by parameter rACHMessage3MCSIndex.

ulbandwidth ul700MHzUpperCBlockEnabled prachFrequencyOffsetn25-5MHz False 2n50-10MHz False 3n100-20MHz False 4

Note that the static scheduler only reserves resources and allocates them to RACH message 3 when a

preamble is detected. Otherwise, the resources remain available and are considered as free by the dynamic

scheduler.

If the system is operating in the 700 MHz upper C band (i.e. if ul700MHzUpperCBlockEnabled is set to

“True”) parameter rACHMessage3StartingPRBIndex must be set to UL NRB - rACHMessage3NumberOfPRBs =

50 - rACHMessage3NumberOfPRBs.

RACH message 3 can only be at the upper end of Zone C .

If the system is not operating in the 700 MHz upper C band (i.e. if ul700MHzUpperCBlockEnabled is set to

“False”), parameter rACHMessage3StartingPRBIndex must be set so that RACH message 3

resources do not overlap with PUCCH resources, i.e. rACHMessage3StartingPRBIndex must be set in the

range [pucchPRBsize/2… UL NRB - pucchPRBsize/2 - rACHMessage3NumberOfPRBs].





3.3 UL Scheduler

3.3.1 UL Static Scheduler [cont.]

Parameter rACHMessage3StartingPRBIndex

rACHMessage3NumberOfPRBs

rACHMessage3MCSIndex

Object ENBEquipment/Enb/LteCell/CellRachConf

ENBEquipment/Enb/LteCell/CellRachConf/CellRachConfFDD

ENBEquipment/Enb/LteCell/CellRachConf

Range & Unit Integer[0..99]

Integer[1..4]

Integer[0..4]

Class/Cat B--Cell / Fixed B--Cell / Fixed B--Cell / Fixed

Value 2 2 3





3.3 UL Scheduler

3.3.2 UL Dynamic Scheduler

The dynamic scheduler is in charge of scheduling all the logical channels which have non-stringent timing constraints and non-regular usage of the resource.

The downlink dynamic scheduler assigns resources to Non-VoIP DTCH (GBR2, GBR3, GBR4 and non-GBRs) and DCCH (SRB1 and SRB2).

The uplink dynamic scheduling algorithm follows the following steps:

Buffer estimation.QoS priority weight calculation.Channel estimates update.Spectrum efficiency correction.Scheduling stage (scheduling of dynamic HARQ retransmissions and

scheduling of 1st HARQ transmissions).

The dynamic scheduler allocates the resources left by the static scheduler. When the system is not

configured in the 700 MHz Upper Block C mode, the resources available to the dynamic scheduler vary

depending on whether PRACH is present or message 3 is scheduled and/or the presence of on-going VoIP

calls.

However, if the system is not configured in the 700 MHz UpperBlock C, the area

[pRBStartIndexForDynamicPUSCHForCentralRegion, pRBStartIndexForDynamicPUSCHForCentralRegion +

numberOfPRBsForDynamicallyScheduledPUSCHForCentralRegion -1] is managed by the dynamic scheduler

every TTI.





3.3.2 UL Dynamic Scheduler

3.3.2.1 Alpha Fairness Scheduler

Parameter ulSchedPropFairAlphaFactor tunes the alpha fairness factor (thus thebahavior) of the scheduler:

This parameter provides flexibility as to the choice of scheduler behavior, allowing the operator to choose the scheduler behavior they want for their network.

ulSchedPropFairAlphaFactor = 1 yields a maximum C/I scheduler.ulSchedPropFairAlphaFactor = 0.5 yields a fair scheduler.ulSchedPropFairAlphaFactor = 0 yields an increased fairness scheduler.

Parameter ulSchedPropFairAlphaFactor

Object ENBEquipment/Enb/LteCell/CellL2ULConf

Range & Unit Float [0..1] step=0.5

Class/Cat B--Cell / O.D.

Value (ALU default: 0.5)

The dynamic scheduling algorithm is the so-called Alpha Fairness scheduler, which is a generalisation, by

means of parameter ulSchedPropFairAlphaFactor, of thewidely used Proportional Fair scheduler.

Parameter ulSchedPropFairAlphaFactor tunes the alpha fairness factor (thus the bahavior) of the scheduler:

• ulSchedPropFairAlphaFactor = 1 yields a maximum C/I scheduler. The scheduler provides more resources

to UEs in better conditions. The better the radio conditions of the UE, the more resources (and hence the

higher the data rate) it gets.

• ulSchedPropFairAlphaFactor = 0.5 yields a fair scheduler. The scheduler attempts to provide the same

number of RBs to all the UEs (despite their different conditions).

• ulSchedPropFairAlphaFactor = 0 yields an increased fairness scheduler.

The scheduler attempts to allocate the resources in such a way that all the UEs eventually get the same

data rate (which is not the case of the fair scheduler since different radio conditions result in different

data rates even when the number of resources is the same, hence the increased fairness of

the scheduler, as compared to the “regular” fair scheduler).





4 Physical Channels Configuration






4.1 Radio Resources Unit Definition

REG and CCE are defined to allocate resources to control channelREG = 4 consecutive useful RE CCE = set of 9 Resource Element Groups (REGs), i.e 36 useful RE

Reference symbols

1 slot

1 REG=4 RE

1 CCE= 9 REG=36 useful RE

1 CCE bandwidth = 0.62 MHz

REG = Resource Element Group

CCE = Control Channel Element





4. Physical Channels Configuration

4.2 Reference Signal

One Downlink Reference Signal is transmitted per downlink antenna portDepending on the number of antenna available in the eNodeB, the number of reference

Signals/ RB is different (8 for 1 antenna, 16 for 2 antennas).

Frequencies

Time

1

0

1

0

0

1

0

1

1

0

1

0

0

1

0

1

RB – 1st slot RB – 2nd slot

RE for RS on antenna 1 & unused on antenna 0

RE for RS on antenna 0 & unused on antenna 1






4.3 Synchronization Signals

In addition to the Reference Signals, the eNodeB also sends the Synchronization Signals, Primary and Secondary, at pre-determined position in the frequency and time domain.

The following drawing shows the format of the RB containing the Synchronization signals:

1

0

1

0

0

1

0

1

1

0

1

0

0

1

0

1

SSS: second to last OFDM symbol of the first slot) of subframes 0 and 5 for SSS

frequency domain: The 72 central subcarriers

PSS: last OFDM symbol of the first slot) of subframes 0 and 5

The synchronization signals are transmitted on 2 × 1 × 72 = 144 REs (72 subcarriers

of the same OFDM symbol are used in 2 of the 10 subframes) each:

• In the frequency domain: The 72 central subcarriers, i.e. if subcarriers used

by Reference Signals are not counted:

o Subcarriers 114 to 185 in case of a 5 MHz bandwidth.



• In the time domain:

o OFDM symbol 6 (last OFDM symbol of the first slot) of subframes 0

and 5 for the primary synchronization signal.

o OFDM symbol 5 (second to last OFDM symbol of the first slot) of

subframes 0 and 5 for the secondary synchronization signal






4.4 The Physical Broadcast Channel (PBCH)

The Broadcast Control Channel (BCCH) is used to broadcast system information: needs to be heard over entire cell coverage area

The BCCH conveys RRC messages called SystemInformation (SI)A particular SI carries a number of System Information Blocks (SIBs) that have the same scheduling period (i.e. RACH info, power control info, etc.)

A special SI that carries minimum required amount of information for PDCCH decoding, the Master Information Block (MIB)

RE for PBCH

Note:

PBCH is transparent from a DL scheduler perspective as there is no MAC header and this is not granted over PDCCH but permanently assigned, also the content of the PBCH is built at RRC level





4 Physical Channel Configuration

4.5 PCFICH

Physical Control Format Indicator Channel (PCFICH) indicates the number of OFDM symbols which are used to transmit L1/L2 control (PDCCH, PHICH)

CFI = {1, 2, 3, 4} (4 is reserved for future use) QPSK modulation is usedCFI indicates if n = 1, 2, or 3 OFDM symbols

PCFICH uses 4 REGs (= 16 RE) and is mapped to the 1st OFDM symbol in fixed positions

4 REGs are uniformly distributed over the system bandwidth for diversityShifted according to cell ID

1st OFDM symbol





4.5 PCFICH

4.5.1 cFI

Parameter cFI dynamicCFIEnabledObject ENBEquipment/Enb/LteCell/CellL1L2ControlChannelsConf

Range & Unit Integer [1..3] Boolean True/False

Class/Cat B--Modem+Cell(s) / Optimization - Tuning

ValueEngineeringRecommandation

n25- 5MHz 3 It is recommended to setdynamicCFIEnabled to “True”

n50- 10MHz 3

N100- 20Mhz 2

In LA3.0, if dynamic configuration of CFI is enabled by parameter dynamicCFIEnabled.

The Physical Control Format Indicator Channel is located in the first OFDM symbol of each subframe and

spans over 4 REGs uniformly distributed over the system bandwidth.

The REs of this time/frequency area are grouped 4 by 4 into Resource Element Groups (REGs). Note that

REGs do not contain RS REs.

It is recommended to set dynamicCFIEnabled to “True” so that the CFI is dynamically

adjusted to use the lowest value needed for PDCCH usage.

This makes more OFDM symbols available to PDSCH when PDCCH usage is low (fewer users),

resulting in higher throughputs. In this case parameter cFI is ignored.





4.5 PCFICH

4.5.1 cFI [cont.]

When dynamicCFIEnabled:: True, then CFI value is determined whenever a

UE context is added or removed by comparing the number of UE contexts with

predefined thresholds provided by configurable OAM parameters, as follows:

If numberOfUEContexts > cFIThreshold2

if cFI3Allowed = True, then the CFI is set to 3

else if cFI2Allowed = True, then the CFI is set to 2

else if cFI1Allowed = True, the the CFI is set to 1

If cFIThreshold1 < numberOfUEContexts ≤ cFIThreshold2

if cFI2Allowed = True, then the CFI is set to 2

else if cFI3Allowed = true, then the CFI is set to 3


If numberOfUEContexts ≤ cFIThreshold1

if cFI1Allowed = true, then the CFI is set to 1



where: numberOfUEContexts is the number of UE contexts (RRC Connected UEs) in the cell






4.6 PDCCH

PDCCH carries Downlin Control Information (DCI) used for scheduling grants and uplinkpower control

Depending on the cFI value, 3 configurations are possible for PDCCH.

The REs used by PDCCH are available over the entire bandwidth, thus the PDCCH capacity depends on the parameterfrequencyBandDownlink in addition to thecFI& PHICH configuration.

15 KHz

Freq

uenc

ies

Time

RB – 1st slot RB – 2nd slot

0.5 ms 0.5 ms

RE for PDCCH

PDCCH with CFI set to 3






4.6 PDCCH [cont.]

For PDCCH, the REGs are grouped into (Control Channels Candidates) CCEs, one CCE being composed of 9 REGs:

1 CCE is composed of 9 × 4 = 36 REs.PDCCH transmission is mapped to a set of 1, 2, 4, or 8 CCEs

RE

CCE=36RE

REG

The PDCCH area contains search spaces, which consist of a set of PDCCH candidates.

A PDCCH candidate is an aggregate of L CCEs There is a search space specific to each connected UE and a search space common to all UEs.

PDCCH with CFi = 3

Common search space UE1 UE2 UE3 UE4

The number of CCEs available per subframe (which determines the total number of scheduling grants

available) depends on the system bandwidth, CFI configuration & PHICH resources

Note that the common and UE-specific search spaces may overlap.

The PDCCH is divided into 2 spaces:

The common search space: The common search space is used by the DL scheduler to send pages and D-BCH data. It is decoded by any UE in the Idle or in RRC Connected state.

UE-specific search space: The principle is that a given UE does not decode all the CCEs over PDCCH but only part of them, i.e. its specific search space CCEs






4.6 PDCCH [cont.]

Each UE monitors the common search space and its specific UE search space for possible grants.At aggregation level L , the total number of PDCCH candidates M (L) per search space

is given by the following table:

Number of PDCCH candidates per search space

The common search space occupies the first 16 CCEs in the PDCCH region.

The UE-specific search space is identified by the UE’s C-RNTI

Search Space Type Aggregation L Number of PDCCH Candidates M(L)

UE Specific

1 6

2 6

4 2

8 2

Common4 4

8 2

The UE monitors a set of candidate PDCCHs every non-DRX subframe Set of candidate PDCCHs are

organized into “search spaces

A search space is a contiguous set of CCEs at a particular aggregation level

Starting CCE index for search space is a function of the subframe number and UE’s assigned C-RNTI

Number of control channel candidates a UE monitors in a given subframe depends

on the selected CCE aggregation level:

· 6 control channel candidates for CCE aggregation level = 1 or 2 (UE-specific)

· 2 control channel candidates for CCE aggregation level = 4 or 8 (UE-specific)

· 4 control channel candidates for CCE aggregation level = 4 (common)

· 2 control channel candidates for CCE aggregation level = 8 (common)





4.6 PDCCH

4.6.1 DCI

Format Purpose Description

0 UL PUSCH Grant RB assignment, MCS, hopping flag, NDI, cyclic-shift of DM-RS, CQI request, 2-bit PUSCH TPC command

1 DL PDSCH Grant for Single Code Word

Resource alloc. header, RB allocation, MCS, HARQ PID, NDI, RV, 2-bit PUCCH TPC command

1A Compact DL PDSCH Grant for Single Code Word

Same as format 1, but with reduced RB allocation flexibility (i.e. PRB must be contiguous). Shall be used for DL signaling.

1BCompact DL PDSCH Grant

with precodinginformation

Same as format 1A with transmission of PMI information forPrecoding

1C Very Compact DL PDSCH grant

Reduced payload for improved coverage: always uses QPSK on assoc. PDSCH, restricted RB assignment, restricted TBS, no HARQ information

1DCompact DL PDSCH Grant with precoding and power

offset information

Same as format 1A. Transmit PMI information for Precoding, DL power offset

2 CL MIMO DL GrantSame as format 1, but MCS/NDI/RV is per codeword, and information on the selected # of layers and precoding matrix index is included for each codeword. Used in CL-MIMO Mode.

2A OL MIMO DL Grant Same as format 2, without precoding matrix index. Used in OL-MIMO Mode.

3 2-bit UL Power Control TPC commands for 14 UEs plus 16 bit CRC3A 1-bit UL Power Control TPC commands for 28 UEs plus 16 bit CRC





4.6 PDCCH

4.6.2 UE specific and Common Search Spaces Parameters

Parameter pdcchAggregationLevelForUESearchSpace

pdcchAggregationLevelForCRNTIGrantsInCommonSearchSpace

Object ENBEquipment/Enb/LteCell/CellL1L2ControlChannelsConf

Range & Unit Enumerate {1, 2, 4, 8} Enumerate { 4, 8}


Value 4EngineeringRecommandation

n25- 5MHz 2

n50- 10MHz 2 & 4

N100- 20Mhz 4

dlBandwidth: pdcchAggregationLevelForUESearchSpacen25-5MHz: The only supported value is 2

n50-10MHz: The only supported values are 2 and 4

n100-20MHz: The only supported value is 4






4.7 PHICH

Physical HARQ Indicator Channel (PHICH) carries the ACK/NACK in the downlink to support uplink HARQPHICH channels are grouped in PHICH groups. Each PHICH group consists of 8 PHICH channels (hence conveys 8 ACK/NACKs).PHICH channels of a same group being separted by orthogonal sequences.PHICH group occupies 3 REGs (= 12 RE) and uses BPSK modulationImplicit mapping is used between location of 1st PRB in UL allocation and PHICH group/sequence

•REG for PCFICH •REG for PHICH group 1 •REG for PHICH group 2

•cell ID=0

•cell ID=1

•cell ID=2

•cell ID=3

•cell ID=4






4.7 PHICH [cont.]

In FDD, the number of PHICH groups in a subframe is:

Where: Ng €{1/6, ½, 1, 2 } and is configured by parameter PhichResourceA PHICH group consists of 3 REGs over either 1 or 3 OFDM symbols, depending on the value of parameter phich-Duration (“normal” or “extended”).

Parameter phichResourceObject ENBEquipment/Enb/LteCell/TxDivOrMimoResources/Power

Off setConfiguration

Range & Unit Enumerate {oneSixth , half , one , two }Class/Cat B--Cell / Optimization – Selection

Value 1

Total Number of PCFICH Group

n25- 5MHz 4

n50- 10MHz 7

N100- 20Mhz 13

In LA3.0, this parameter is hardcoded to “normal”. Hence PHICH is always

located in the first OFDM symbol of each subframe.






4.8 The Physical Downlink Shared Channel (PDSCH)

PDSCH consists of the remaining resources, i.e. the PRBs that are occupied neither by synchronization signals, nor by PBCH nor by control channels (PCFICH, PHICH, PDCCH).

PDSCH is transmitted in TxDiv or MU-MIMO (2-layer OL-MIMO, 2-layer CL-MIMO or 1-Layer CL-MIMO)






4.9 Sounding Reference Signal

Sounding reference signal (SRS) is used to sound uplink channel

to support frequency selective scheduling

Channel sensitive scheduling in both time and frequency

SRS parameters are UE specific and configured semi-statically:

1 symbol in subframe used for SRSPeriodicity: {2, 5, 10, 20, 40, 80, 160, 320} msBandwidth: typically transmitted over the entire PUSCH bandwidth

SRS

0.5ms 0.5ms

SRS

SRS is not sent when there is a scheduling request (SR) or CQI to be sent on PUCCH (to avoid multi-carrier transmission)






4.9 Sounding Reference Signal [cont.]

In LA3.0 The SRS is transmitted on on or two combs.Up to 8 SRSs ca be multiplexed in a single TTI (4 per comb)The eNB supports different SRS periods for different UEs: (the period grox as the number of users increases in order to fit the SRS of each UE)- In LA3.0, there can be up to 3 period configurations assigned among all users.- The first UEs have an SRS period of:

· 5ms if the maximum number of active UEs allowed in the cell is less than or equal to 100 (maxnumberofusers =<100)

· 2àms if the maximum number of active UEs allowed in the cell is greater than 100 (maxnumberofusers>100)

0.5ms

0.5ms

Comb 1 Comb 2

SRS





4.9 Sounding Reference Signal

4.9.1 SRS Related Parameters

Parameter srsEnabled sRSDuration srsBandwidthConfiguration

Object ENBEquipment/Enb/LteCe ll

ENBEquipment/Enb/LteCell/CellL1ULConf

Range & Unit Boolean True/False

Enumerate{one shot, infinite}

Enumerate{bw0, bw2, bw3, bw6, bw7}

Class/Cat B--Modem+Cell(s) / Fixed

Value true Infinite SRS BW inPRBs

5 Mhz 10 Mhz 20Mhz

Engineering Recommendation

bw0 36 48 96*

bw2 24 40 80*

bw3 20 * 36* 72

bw6 8 20 48

bw7 4 16 48

* Not supported in LA3.0






4.10 Physical Uplink Control Channel (PUCCH)

PUCCH carries ACK/NACK and CQI to support the downlink, as well as scheduling requests (SR) for the uplink.

The PUCCH occupies pucchPRBsize = 4 or 6 or 8 PRBs, depending on the system bandwidth

resource 1

resource 0

0.5ms slot

resource 0

resource 1

0.5ms slot

System BW

resource 2 resource 3

resource 2resource 3

PUCCHPUSCH

ulBandwidth NRB UL pucchPRBsize

n25 – 5MHz 25 4

n50- 10MHz 50 6

n100-20Mhz 100 8





4.10 Physical Uplink Control Channel (PUCCH)

4.10.1 Scheduling Request Over PUCCH

In LA2.0 UE is configured with 20ms SR, but sue to the collision with semi static PUSCH transmissions at the same TTI, it never transmits it.The scheduler considers that the UE is candidate for an UL grant if the corresponding UL Buffer Occupancy estimation is not equal to 0For that purpose, periodic small increases of the UL BO estimator are used in order to send small grants regularly to the UE.Lack of actual support SR causes resources waste, especially with a high number of UEs

In LA3.0, the support of SR is introduced:This provides more efficient method for the UE to request UL scheduling.Upon reception of a SR, the buffer occupancy estimate is increased in the amount configured by parameter macBOIncreasedUponResourceRequestUI, fo each of the related logical channels

SR periods grow as the number of UEs increases in order to fir the SR of each UE.





5 Transmit Power





5 Transmit Power

5.1 Downlink Transmit Power

Let Pmax-hardware be the maximum transmit power of one RF Module Power Amplifier,expressed in dBm.

The hardware equipments available in LA3.0 have either:

30 Watts power capacity (Pmax-hardware = 44.7 dBm).40 Watts power capacity (Pmax-hardware = 46.0 dBm).

Parameter cellDLTotalPower is used, if need be, to impose additional limits on the total power transmitted by a power amplifier;

The value of cellDLTotalPower is converted into linear scale according to the following Equation: P Max[mW]= 10 cellDLTotalPower/10

Parmeter cellDLTotalPower

Object ENBEquipment/Enb/LteCell

Range & Unit Float [0..50] step=0.1 dBm

Class/Cat B--Cell / Depends on capacity license

Value 10

If this parameter is set to a value higher than Pmax-hardware, the cell setup will fail

and an alarm will be generated by the eNB as a result of that.






5.1.1 cellDLTotalPower Parameter

The available transmit power per power amplifier is controlled by licensing. Consequently, the value of parameter cellDLTotalPower must not exceed certain values, as illustrated in the table below:

Power Amlifier HWCapacity Transmission Power

Max possible value forparameter

cellDLTotalPower

30 W

10 W 40.0

20 W 43.0

30 W 44.7

10 W 40.0

40 W

20 W 43.0

30 W 44.7

40 W 46.0






5.1.2 Reference Signal Power Setting

Parameter referenceSignalPower configures the DL RS absolute power applied per Resource Element (RE) and per transmit antenna.

This level is used as a power level reference (the power levels for all the other DL signals and channels are set relative to it).

This parameter is expressed in dBm. It is converted into linear scale (milliwatt) according To: P Max[mW]= 10ReferenceSignalPower/10

Parmeter referenceSignalPower

Object ENBEquipment/Enb/LteCell/TxDivOrMimoResources/PowerOffsetConfiguration

Range & Unit Float [0..50] step=0.1 dBm

Class/Cat Integer[-60..50] dBm






5.1.2 Reference Signal Power Setting [cont.]

The default setting for parameter referenceSignalPower is as follows:

CELLdl Total Power dlBandwidth ReferenceSignalPower

40.0

5MHz 15

10MHz 12

20MHz 9

43.0

5MHz 18

10MHz 15

20MHz 12

44.7

5MHz 19

10MHz 16

20MHz 13

46.0

5MHz 21

10MHz 18

20MHz 15

Parameter referenceSignalPower

This parameter is a key RF optimization parameter that influences the cell coverage. It is set according to

the cell size. The higher the setting, the larger the cell coverage on the downlink, but leaves smaller power

headroom available for other downlink signals and channels.






5.1.3 Synchonization Signals Power Setting

Parameters primarySyncSignalPowerOffset and secondarySyncSignalPowerOffsetconfigure the transmit power per RE and per transmit antenna

Parmeter primarySyncSignalPowerOffset secondarySyncSignalPowerOffset

Object ENBEquipment/Enb/LteCell/TxDivOrMimoResources/PowerOff setConfiguration

Range & Unit

Float [-25.6..25.5] step=0.1 dB

Class/Cat B--Cell / Optimization - Tuning

CELLdlTotal Power

Dl BW PSSPOffset

SSSPOffset

CELLdlTotal Power

DL BW PSSPOffset

SSSPOffset

40.0

5MHz 1.5 1.5

44.7

5MHz 3.0 3.0

10MHz 2.0 2.0 10MHz 3.0 3.0

20MHz 2.0 2.0 20MHz 3.0 3.0

43.0

5MHz 1.5 1.5

46.0

5MHz 1.5 1.5

10MHz 2.0 2.0 10MHz 2.2 2.2

20MHz 2.0 2.0 20MHz 2.3 2.3

Expressed in dB relative toPREF for PSS & SSS respectively. They are converted into linear scale (milliwatt)

according to

P P-SCH [mW]= PREF X 10 PrimarySyncSignalPowerOffset/10

P S-SCH [mW]= PREF X 10 SecondarySyncSignalPowerOffset/10





5 Transmit Power

5.2 PBCH

Parameter pBCHPowerOffset configures the transmit power per RE and per transmit antenna (expressed in dB relative to PREF ) for the PBCH channel.

PBCH is transmitted at – 3dB compared to the parameter setting due to TxDiv encoding.

Parmeter pBCHPowerOffsetObject ENBEquipment/Enb/LteCell/TxDivOrMimoResources/P

owerOff setConfiguration

Range & Unit Float[-25.6..25.5] step=0.1 dB


Parameter pBCHPowerOffset is a key RF optimization parameter.

This parameter is expressed in dB, relative to the RS power, PREF. It is converted into inear scale (milliwatt) according to:

P PBCH[mW]= PREF X 10 (pBCHPowerOffset-3)/10





5 Transmit Power

5.2 PBCH [cont.]

The higher the setting, the more robust the PBCH reception within the cell coverage area, but this reduces the power available for other downlink signals and channels.

The current default setting for parameter pBCHPowerOffset is the following:

CELLdl Total Power dlBandwidth pBCHPowerOffset

40.0

5MHz 3.5

10MHz 3.5

20MHz 3.1

43.0

5MHz 3.5

10MHz 3.5

20MHz 3.1

44.7

5MHz 3.1

10MHz 3.1

20MHz 3.1

46.0

5MHz 3.8

10MHz 4.5

20MHz 4.5





5 Transmit Power

5.3 PCFICH Power Setting

Parameter pCFICHPowerOffset configures the transmit power per RE and per transmit antenna (expressed in dB relative to PREF ) for the PCFICH.

This parameter is expressed in dB, relative to the RS power, PREF. It is converted intolinear scale (milliwatt) according to/

PPCFICH [mW] = PREF x 10 (pCFICHPowerOffset -3)/10

PCFICH is transmitted at –3dB compared to the parameter setting due to TxDiv encoding.

Parmeter pCFICHPowerOffset




This is a key RF optimization parameter: The higher the setting, the more robust the CFI reception within

the cell coverage area, but this reduces the power available for other downlink singals and channels.

Smaller settings will impair CFI, hence PDCCH reception.





5 Transmit Power

5.3 PCFICH Power Setting [cont.]

The current default setting for parameter pCFICHPowerOffset is the following:

CELLdl Total Power dlBandwidth pCFICHPowerOffest

40.0

5MHz 5.5

10MHz 6.0

20MHz 6.0

43.0

5MHz 5.5

10MHz 6.0

20MHz 6.0

44.7

5MHz 6.0

10MHz 6.0

20MHz 6.0

46.0

5MHz 6.0

10MHz 6.0

20MHz 6.0





5 Transmit Power

5.4 PHICH Power Setting

Parameter pHICHPowerOffset configures the transmit power per RE and per transmit antenna (expressed in dB relative to PREF ) for the PHICH channel.

This parameter is expressed in 3dB, relative to the RS power, PREF. It is convertedinto linear scale (milliwatt) according to:

P PHICH[mW]= PREF X 10(pHICHPowerOffset-3)/10

PHICH is transmitted at –3dB compared to the parameter setting due to TxDiv encoding.

Parmeter pHICHPowerOffset








5 Transmit Power

5.4 PHICH Power Setting [cont.]

The current default setting for parameter pHICHPowerOffset is as follows:

Celldl Total Power dlBandwidth pHICHPowerOffest

40.0

5MHz 5.6

10MHz 6.0

20MHz 6.0

43.0

5MHz 5.6

10MHz 6.0

20MHz 6.0

44.7

5MHz 6.0

10MHz 6.0

20MHz 6.0

46.0

5MHz 6.1

10MHz 6.4

20MHz 6.4





5 Transmit Power

5.5 PDCCH Power Setting

The PDCCH transmit power is either determined by the PDCCH power control algorithmor derived from parameters pDCCHPowerOffsetSymbol1 and pDCCHPowerOffsetSymbol2and3

pDCCHPowerControlActivation:: False >>>>>>The PDCCH transmit power is derived fromParameters:

pDCCHPowerOffsetSymbol1 andpDCCHPowerOffsetSymbol2and3.

pDCCHPowerControlActivation:: True>>>The PDCCH transmit power is initialized and derived from Parameters:pDCCHPowerOffsetSymbol1 andpDCCHPowerOffsetSymbol2and3:and then updated by the PDCCH power control algorithm

1

0

1

0

0

1

0

1

1

0

1

0

0

1

0

1

pDCCHPowerOffsetSymbol2and3(expressed in dB relative to PREF)

pDCCHPowerOffsetSymbol1(expressed in dB relative to PREF)

RB

Parameter pDCCHPowerOffsetSymbol1 configures the transmit power of PDCCH (expressed in dB relative

toPREF ) per RE and per Power Amplifier, in the first OFDM symbol.

Parameter pDCCHPowerOffsetSymbol2and3 configures the transmit power of PDCCH (expressed in dB

relative toPREF ) per RE and per Power Amplifier, in the second and third OFDM symbols.

These 2 parameters are expressed in dB, relative to the RS power, PREF. They are converted into linear

scale (milliwatt) according to:

PDCCH1= PREF X 10 (pDCCHPowerOffsetSymbol1_3)/10

PDCCH 2,3=P REF X 10 (pDCCHPowerOffsetSymbol2and3-3)/10





5 Transmit Power

5.5 PDCCH Power Setting [cont.]

Parmeter pDCCHPowerControlActivation pDCCHPowerOffsetSymbol1

pDCCHPowerOffsetSymbol2and3

Object ENBEquipment/Enb/LteCell/TxDivOrMi moResources/PowerOff setConfiguration

Range & Unit Boolean True/False Float[-25.6..25.5] step=0.1 dB

Class/Cat B--Cell / Fixed B--Cell / Optimization - Tuning

Value n25-5MHz, True See Recommandation

n50-10MHz True

n100-20MHz False





5.5.1 pDCCHPowerOffsetSymbol1 & pDCCHPowerOffsetSymbol2&3

Celldl Total Power dlBandwidth pDCCHPowerOffsetSymbol1 pDCCHPowerOffsetSymbol2&3

40.0

5MHz 3.2 3.2

10MHz 3.2 3.2

20MHz 3.4 3.4

43.0

5MHz 3.2 3.2

10MHz 3.0 3.0

20MHz 3.5 3.2

44.7

5MHz 4.0 3.9

10MHz 4.0 3.9

20MHz 4.0 3.9

46.0

5MHz 3.0 3.2

10MHz 3.2

20MHz 3.2





5 Transmit Power

5.6 PDSCH Power Setting

PPDSCH _ A[mW] is the transmit power of PDSCH REs in OFDM symbols 1, 2, 3, 5 and 6 and is configured by parameter paOffsetPdsch:

PPDSCH _ A[mW] = PREF X 10 paOffsetPdsch/10

PPDSCH _ B[mW] is the transmit power of PDSCH REs in OFDM symbols 0 and 4 and is derived based on parameters paOffsetPdsch and pbOffsetPdsch as follows:

pbOffsetPdsch PPDSCH _ B[mW]

0 PREF X 10 (1.0 + paOffsetPdsch)/10

1 PREF X 10 paOffsetPdsch/10

2 PREF X 10 (-1.2 + paOffsetPdsch)/10

3 PREF X 10 (-3.0 + paOffsetPdsch)/10

0 1 2 3 4 5 6 0 1 2 3 4 5 6

RS RS

RS RS RS

RS RS

RS

RSRS RS RS

RS RS RS RS





5 Transmit Power

5.6 PDSCH Power Setting [cont.]

The enumerate values are mapped to the values used in the equation

PPDSCH _ A[mW] = PREF X 10 paOffsetPdsch/10 according to the table below:

Enumerate Value Value used in the derivationPPDSCH _ A[mW] = PREF X 10 paOffsetPdsch/10

Enumerate Value

Value used in the derivationPPDSCH _ A[mW] = PREF X 10 paOffsetPdsch/10

dB-6(0) -6 dB dB0 (4) 0 dB

dB-4dot77(1) -4.77 dB dB1 (5) 1 dB

dB-3 (2) -3 dB dB2 (6) 2 dB

dB-1dot77 (3) -1.77 dB dB3 (7) 3 dB

Parmeter paOffsetPdsch pbOffsetPdsch


Range & Unit Enumerate{dB-6, dB-4dot77, dB-3, dB-1dot77, dB0, dB1, dB2, dB3 }

Integer[0..3]

Class/Cat B--Cell / Optimization - Selection B--Cell / Fixed

Value See below 1





5 Transmit Power

5.7 PDCCH Power Control

When PDCCH power control is activated, the corresponding algorithm aims at increasing the power of the UEs in bad radio conditions:>>> adapting the PDCCH transmit power to the UE’s radio conditions.

CQI-to-SINR lookup tableCQI ≈≈≈ Estimated SINR

CQI

Estimated SINR < Target SINR:The power is increased [target SINR-Estimated SINR] (in the linear scale) goes to zero. The power increase is limited though. The limit is configured by parameterpDCCHPowerControlMaxPowerIncrease.

Estimated SINR > Target SINR:The power is decreased [Estimated SINR-target SINR] (in linear scale) goes to zero. The power decrease is limited though.The limit is configured by parameterpDCCHPowerControlMaxPowerDecrease.

The UE’s SINR is derived based on the CQI it reports and by means of the CQI-to-SINR lookup table

configurable through parameter cQIToSINRLookUpTable.

• If the target SINR is not reached (Estimated SINR< target SINR), the power is increased so that the

difference [target SINR-Estimated SINR] (in the linear scale) goes to zero. The power increase is limited

though. The limit is configured by parameter pDCCHPowerControlMaxPowerIncrease.

• If the target SINR is exceeded (Estimated SINR> target SINR), the power is decreased so that the

difference [Estimated SINR-target SINR] (in linear scale) goes to zero. The power decrease is limited

though. The limit is configured by parameter pDCCHPowerControlMaxPowerDecrease.





5 Transmit Power

5.7 PDCCH Power Control [cont.]

Parmeter pDCCHPowerControlMaxPowerIncrease

pDCCHPowerControlMaxPowerDecrease

Object NBEquipment/Enb/LteCell/CellL2DLConfRange & Unit Float

[0..12.7] step = 0.1 dBFloat[0..12.8] step = 0.1 dB


Value 6.7 12.8





5 Transmit Power

5.8 Downlink Power Budget

While configuring the cell, the eNB verifies that the available power is not exceeded.The eNB computes the total power consumed in every symbol period as follows:

TotalPowerRS = nbRERS × PREFTotalPowerP-SCH = nbREP-SCH × PP-SCH

TotalPowerS-SCH = nbRES-SCH × PS-SCH

TotalPowerPBCH = nbREPBCH × PPBCH

If pDCCHPowerControlActivation is set to False

TotalPowerPDCCH = nbREPDCCH × PPDCCH1 (The first OFDM symbol of slot 0)TotalPowerPDCCH = nbREPDCCH × PPDCCH2,3 (The 2nd or 3rd OFDM symbol of slot 0)

While configuring the cell, the eNB verifies that the available power is not exceeded, taking into account

the RS power, the SCH powers, the PBCH power, the PCFICH power, the PHICH power, the PDCCH power

and the PDSCH power.

• nbRERS: ∑RE of the Reference Signal in the considered OFDM symbol.

• nbREP-SCH: ∑ RE of the primary SCH in the considered OFDM symbol.

• nbRES-SCH: ∑ RE of the secondary SCH in the considered OFDM symbol.

• nbREPBCH: ∑ RE of the PBCH in the considered OFDM symbol.

• nbREPDCCH: ∑ RE of the PDCCH in the considered OFDM symbol.

• nbREPCFICH: ∑ RE of the PCFICH in the considered OFDM symbol.

• nbREPHICH: ∑ RE of the PHICH in the considered OFDM symbol.

• nbREPDSCH: ∑ RE of the PDSCH in the considered OFDM symbol.

TotalPowerRS: total power used by Reference Signal in the current OFDM symbol.

TotalPowerP-SCH: total power used by the primary Synchronization signal in thecurrent OFDM symbol.

TotalPowerS-SCH: total power used by the secondary synchronization signal in thecurrent OFDM symbol.

TotalPowerPBCH: total power used by the PBCH in the current OFDM symbol.

TotalPowerPDCCH: total power used by the PDCCH in the current OFDM symbol.





5 Transmit Power

5.8 Downlink Power Budget [cont.]

If pDCCHPowerControlActivation is set to TrueTotalPowerPDCCH is initialized at cell setup as for the case when PDCCH power control is

deactivated and then updated by the PDCCH power control algorithm.

TotalPowerPCFICH = nbREPCFICH × PPCFICHTotalPowerPHICH = nbREPHICH × PPHICHTotalPowerPDSCH = nbREPDSCH × PPDSCH_A (For the OFDM symbol index 1, 2, 3, 5 or 6)TotalPowerPDSCH = nbREPDSCH × PPDSCH_B (For the OFDM symbol index 0 or 4)

The sum of the transmitted power on all physical channels and signals must be configured within the limit configured through parameter cellDLTotalPower for each OFDM symbol.

Thus, for every OFDM symbol, the power budget algorithm performs the following checking:

(TotalPowerRS + TotalPowerP-SCH + TotalPowerS-SCH + TotalPowerPBCH +TotalPowerPDCCH + TotalPowerPCFICH + TotalPowerPHICH + TotalPowerPDSCH) ≤ PMax

(TotalPowerRS + TotalPowerP-SCH + TotalPowerS-SCH + TotalPowerPBCH +TotalPowerPDCCH + TotalPowerPCFICH + TotalPowerPHICH + TotalPowerPDSCH) ≤ PMax

TotalPowerPCFICH: total power used by the PCFICH in the current OFDM symbol.TotalPowerPCFICH = nbREPCFICH × PPCFICH

TotalPowerPHICH: total power used by the PHICH in the current OFDM symbol.TotalPowerPHICH = nbREPHICH × PPHICH

TotalPowerPDSCH: total power used by the PDSCH in the current OFDM symbol• If the current OFDM symbol index is 1, 2, 3, 5 or 6TotalPowerPDSCH = nbREPDSCH × PPDSCH_A

• If the current OFDM symbol index is 0 or 4TotalPowerPDSCH = nbREPDSCH × PPDSCH_B

The sum of the transmitted power on all physical channels and signals must be configured within the limit configured through parameter cellDLTotalPower for each OFDM symbol.The power budget algorithm consists thus in performing the following checking for every OFDM symbol:(TotalPowerRS + TotalPowerP-SCH + TotalPowerS-SCH + TotalPowerPBCH + TotalPowerPDCCH +

TotalPowerPCFICH + TotalPowerPHICH + TotalPowerPDSCH) ≤ PMax

If the condition above is not satisfied for at least 1 OFDM symbol, the cell setup fails, (meaning the cell does not go on air) and an alarm is generated by the eNB.Note that the checking discussed above is only performed for subframes 0, 1 and 5 for if the conditions above are satisfied in these 3 subframes, they are statisfied in the other subframes (i.e. subframes 2, 3, 4, 6, 7, 8 and 9).





Slot Slot 0/ Subframe 1 Slot 0/ Subframe 1

OFDM Symbol 0 1 2 3 4 5 6 0 1 2 3 4 5 6

Number of REs 50 0 0 0 50 0 0 50 0 0 0 50 0 0

nbRERS 0 0 0 0 0 0 62 0 0 0 0 0 0 0

nbREP-SCH 0 0 0 0 0 62 0 0 0 0 0 0 0 0

nbRES-SCH 0 0 0 0 0 0 0 48 48 72 72 0 0 0

nbREPBCH 136 300 300 0 0 0 0 0 0 0 0 0 0 0

nbREPDCCH 16 0 0 0 0 0 0 0 0 0 0 0 0 0

nbREPCFICH 48 0 0 0 0 0 0 0 0 0 0 0 0 0

nbREPDSCH-A 0 0 0 300 0 228 228 0 228 228 228 0 300 300

nbREPDSCH-b 0 0 0 0 200 0 0 152 0 0 0 200 0 0

Unused RE 50 0 0 0 50 10 10 50 24 0 0 50 0 0

5.8 Downlink Power Budget

5.8.1 RE Distribution in slot 0 & 1 of Subframe 0 (5 Mhz)

The RE distribution for each OFDM symbol in subframe 0 for phichResource = one and cFI = 3 (with 5)

The RE distribution in subframe 1 is obtained by setting nbREP-SCH , nbRES-SCH and nbREPBCH to 0 in the

RE distribution of subframe 0.

The RE distribution in subframe 5 is obtained by setting nbREPBCH to 0 in the RE distribution of subframe 0.





6 Uplink Power Control





PUCCH power control is used to guarantee the required error rates of control

channels and to maintain orthogonally among the users that are code multiplexed in the

same time frequency resource.

The principles of PUCCH power control are the following:

PUCCH is power controlled independently from PUSCHPower control command is signaled to the UE: This is sent to the UE in DCI Format 1 or 2, when dynamic grant for DL allocation is available. Otherwise, the command is sent in DCI Format 3.DCI3 format is used for TPC group command: It uses the common search space of PDCCH and it is enabled disabled using dciFormatSelectorForTPC


6.1 PUCCH Power Control

PDCCH (DCI Format 1 or 2)/DCI Format 3

PPUCCH (i) = min{Pmax ,P0 _ PUCCH + PL + Δ F _ PUCCH + g(i)} [dBm]

ΔF _ PUCCH denotes the power offset. It depends on the PUCCH format. This parameter is hardcoded in formats 2/2a/2b. For formats 1 and 1b, it is

configured by parameters deltaFPUCCHFormat1 and deltaFPUCCHFormat1b, respectively.

Note that each of the signaled values ΔF_PUCCH is a 2-bit value in dB relative to PUCCH Format 1a.

• P0_ PUCCH is a parameter composed of the sum of a 5-bit cell specific component P0_NOMINAL_PUCCH configured

by OAM parameter

p0NominalPUCCH and a UE specific component P0_UE_PUCCH configured by OAM parameter p0uePUCCH.

• δ PUCCH is a UE specific correction value in dB, also referred to as a TPC command, included in a PDCCH

with DCI formats 1/1A/2/2A.

• Accumulated power control rule is used which is described by g(i) = g(i −1) +δ PUCCH (i − 4) where g(i) is the

current PUCCH power control adjustment state in subframe i .

The initial value of g(i) is defined as: g(0) = ΔPrampup +δ Msg2

Where: δ Msg2 is the TPC command indicated in the random access response (RACH message 2).

ΔPrampup is the total power ramp-up from the first to the last preamble configured by parameter

preambleTransmitPowerStepSize.

Mapping of TPC Command Field in DCI Format 1/1A/2/2A :: δ PUCCH [dB]

0 :: -1

1 :: 0

2 :: 1

3 :: 3






6.1 PUCCH Power Control [cont.]

Engineering Recommendation: Parameter p0NominalPUCCH

This parameter is a key RF optimization parameter. Higher settings of this parameter will improve PUCCH

reception, but will also drive higher UE Tx power leading to interference to neighboring cells, and vice-

versa.

The current default value for this parameter is -114.

The PUCCH power control procedure is used to guarantee the required error rate. For this purpose, it aims

at achieving a target SIR the value of which guarantees the required error rate. The SIR target is set to

sIRTargetforReferencePUCCHFormat for PUCCH Format 1A and to sIRTargetforReferencePUCCHFormat +

deltaFPUCCHFormat1b for PUCCH format 1B.

Engineering Recommendation: Parameter sIRTargetforReferencePUCCHFormat

This parameter is a key RF optimization parameter. Higher settings of this parameter will improve PUCCH

reception, but will also drive higher UE Tx power leading to interference to neighboring cells, and vice-

versa.

The current default value for this parameter is -3.0.

ALU recommends that the operator not change the settings for this parameter.






6.2 PUSCH Power Control

For PUSCH power control, the TPC command is embedded in the uplink scheduling grant with DCI0.

UL Power control for dynamic scheduled grant is based on an Open-Loop powercontrol with slow aperiodic Closed-Loop corrections:

The UE receives from the network information about the RS TxPower (in SIB2), andfrom there computes, at any instant, the PPUSCH of the message to be sent in the frame (i) based on the following function:

PPUSCH = 10Log10 (MPUSCH(i)) +p0NominalPUSCH+ PL+ …[dBm]

RS Tx Power• PL (DL RSRP Pathloss =RS TxPower - RSRP)• p0NominalPUSCH• MPUSCH = Number of RBs usedto transmit the message

>> UE Calculates PPUSCH ofthe message to be sent on the frame

Open-Looppower

Control

SIB2:• RS Tx Power

• p0NominalPUSCH

PMAX is the maximum allowed power (depends on the UE power class).

MPUSCH (i) is the bandwidth of the PUSCH transmission expressed in number of resource blocks taken from

the resource allocation valid for uplink

subframe i from the scheduling grant received on subframe i − KPUSCH (with KPUSCH = 4 in FDD).

• P0 _ PUSCH ( j) is the sum of an 8-bit cell specific nominal component P0 _ NOMINAL _ PUSCH ( j) configured

by parameter p0NominalPUSCH and

a 4-bit component P0 _UE _ PUSCH ( j) configured by parameter p0UePUSCH.

Parameter p0UePUSCH is logical channel specific. In case more than one logical channel is configured, the

highest value over the different logical

channels is used.

( The index j=0 is used for PUSCH (re)transmissions corresponding to a persistent scheduling grant and the index j=1 is used for PUSCH (re)transmissions corresponding to a dynamic scheduling grant).

• ΔTF ( TF(i )) = 10log10 (2MPR⋅Ks −1) , where:

- Ks is a cell specific parameter given by RRC. If Ks = 0 , the MCS compensation does not execute.

- TF(i) is the PUSCH transport format valid for subframe i.

- MPR = Modulation × CodingRate = NINFO/ NRE where NINFO is the number of information bits and NRE is the number of resource elements determined from TF(i) and MPUSCH (i) for subframe i.






6.2 PUSCH Power Control [cont.]

The eNodeB computes the SINR of the received message in the UL. Depending on the difference between the SINR measured and the SIR target, the eNodeB

will send TPC (Transmit Power Control) commands to ask the UE to increase or decrease The PPUSCH of its next message: this is the (slow inner-loop) Closed-Loop power control.

PPUSCH = 10Log10 (MPUSCH(i)) + p0NominalPUSCH + PL+ fi} [dBm]fi :is power control adjustments

p0NominalPUSCH is the the necessary level of the received signal at the eNodeB side for the signal to be properly decoded, and this for one RB. It can be expressed as:

p0NominalPUSCH = UL_Interference + SIR_Target

Closed-Looppower

Control

SIBs

SIB2:• RS Tx Power• p0NominalPUSCH

RSRP measured PPUSCH

TPC Command

PUSCH

SIR Target

with f(i) = power control adjustments (if parameter

numberofULmeasurementsNeededForSendingValidTPCCommandForPUSCHdynamicMode is set to 50 –

and because PUSCH SINR is computed from SRS measurement reports, and that SRS is sent every 5ms –,

there will be at the most one TPC command sent every 50*5 = 250ms)

• f (i) is the PUSCH power control adjustment state function.

• The term pUSCHPowerControlAlphaFactor × PL compensates for the path loss:

-PL is the downlink path loss estimate calculated by the UE as PL = RS power − filtered RSRP where the

filtered RSRP is the result of the averaging of RSRP using the configurable filter coefficient

filterCoefficient.

- pUSCHPowerControlAlphaFactor is a cell-specific parameter transmitted as a 3-bit IE in SIB type 2. It

takes values in the set : {0, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 1}:

>>When pUSCHPowerControlAlphaFactor is set to 1, pUSCHPowerControlAlphaFactor × PL = PL and hence

the uplink path loss is fully compensated.

>>When pUSCHPowerControlAlphaFactor is set in {0.9, 0.8, 0.7, 0.6, 0.5, 0.4},

pUSCHPowerControlAlphaFactor × PL < PL and hence the uplink path loss is only partially compensated.

This is known as fractional power control.

>> When pUSCHPowerControlAlphaFactor is set to 0, pUSCHPowerControlAlphaFactor × PL = 0 and hence

the uplink path loss is not compensated at all.






6.2 PUSCH Power Control [cont.]

Of course, the PPUSCH is limited by the maximum power of the UE power class and the maximum UE power allowed by the eNodeB:

PPUSCH = 10.log10(MPUSCH) + p0NominalPUSCH + PL + fi + … becomes then PPUSCH = min { PCMAX, 10.log10(MPUSCH) + p0NominalPUSCH + PL + fi + … }

For information, 3GPP TS36.213 specify the following formula on each subframe i:

PPUSCH = min {PMax,10Log10 (MPUSCH(i)) +P0_PUSCH (j)+ pUSCHPowerControlAlphaFactor x PL+ ΔTF(TF(i))+fi} [dBm]

with:ΔTF(TF(i)) = power offset depending on PUSCH transport format TF(i)pUSCHPowerControlAlphaFactor = αPL = alpha factor for Fractionnal Power Control. P0_PUSCH(for dynamic scheduled grant, j=1) = p0NominalPUSCH + P0_UE_PUSCH(1)

with P0_UE_PUSCH(1): UE specific component set for the moment to 0





6.2 PUSCH Power Control

6.2.1 p0NominalPUSCH & p0UePUSCH Parameters

Parameter p0NominalPUSCH p0UePUSCH

Object ENBEquipment/Enb/LteCell/ULPowerControlConf

Range & Unit Integer[-126..24] step = 1 dBm

Integer[-8..7] step = 1 dBm

Class/Cat B--Modem+Cell(s) / Optimization - Tuning C--New-set-ups / Optimization - Tuning

Value 0


PUSCHPowerControlAlphaFactor p0NominalPUSCH The current default value for parameter and p0UePUSCH is 0.1.0 -108

0.8 -90

0.7 -80

Parameters p0NominalPUSCH and p0uePUSCH are key RF optimization parameters. Higher settings will

improve PUSCH reception, but will also drive higher UE Tx power leading to interference to neighboring

cells, and vice-versa. The current default value for parameter and p0UePUSCH is 0.

The current default value for parameter p0NominalPUSCH given in the table are true for

ul700MHzUpperCBlockEnabled set to FALSE





6.2.2 FilterCoefficient & pUSCHPowerControlAlphaFactor Parameters

Parameter filterCoefficient pUSCHPowerControlAlphaFactor


Range & Unit Enumerate{fc0 (0), fc1 (1), fc2 (2), fc3 (3), fc4 (4), fc5 (5), fc6 (6), fc7 (7),fc8 (8), fc9 (9), fc11 (10), fc13 (11), fc15 (12), fc17 (13), fc19(14)}

Enumerate{ 0(0), 0.4(1), 0.5(2), 0.6(3), 0.7(4), 0.8(5), 0.9(6), 1.0(7) }

Class/Cat C--New-set-ups / Fixed B--Cell / Optimization - Selection

Value Default value is fc4 Default value is 1.0 in ALU templates


It is an optional parameter. If it is not set than it is not sent to the UE. The latter will use the defaut value defined that is fc4.With value fc0 corresponding to k = 0, fc1 corresponding to k = 1, and so on.

This parameter should be set by the operator depending on their strategy. It isdefaulted to 1.0 in ALU templates.

Parameter filterCoefficient is an optional parameter. If it is not set than it is not sent to the UE. The latter

will use the defaut value that is fc4.

Parameter pUSCHPowerControlAlphaFactor is a key RF parameter. Setting it to 1.0 deactivates fractional

power control (i.e. full path loss compensation). As this parameter decreases, the near-cell throughput and

overall cell throughput increase at the expense of a lower cell-edge throughput as a result of fractional

power control (partial path loss compensation).

This parameter should be set by the operator depending on their strategy. It is defaulted to 1.0 in ALU

templates.

Below, we also provide default settings for pUSCHPowerControlAlphaFactor =0.8 and

pUSCHPowerControlAlphaFactor = 0.7. Setting

pUSCHPowerControlAlphaFactor to 0.9 yields a performance quite close to that obtained by setting

pUSCHPowerControlAlphaFactor to 1.0. On the other hand, setting parameter

pUSCHPowerControlAlphaFactor to values lower than 0.7 causes a considerable decrease of cell-edge

throughput.






6.3 Fractional Power Control

Instead of fully compensating for the DL PathLoss, the principal of FPC is to only compensate partially for it:

PPUSCH = 10.log10(MPUSCH) + p0NominalPUSCH + αPLPL + fi + … }with 0 ≤ αPL ≤ 1 (αPL = 1 Full Compensation of PL FPC de-activated)

The partial compensation of the pathloss is equivalent to having a SIR target varying according to the pathloss:

PPUSCH = 10.log10(MPUSCH) + p0NominalPUSCH’ + PL + fi + … }With: p0NominalPUSCH’ = p0NominalPUSCH + αPLx PL – PL

= p0NominalPUSCH - (1-αPL) x PL= UL_Interference + SIR_Target - (1-αPL) x PL

SIR Target

As we reduce a, the range of target SINRs increases between UEs, and we can achieve higher spectral

efficiency at the

expense of cell edge rate In fractional power control, the transmit power adjustment

pUSCHPowerControlAlphaFactor × PL compensates for only a fraction of the estimated path loss PL . The

result is that the SINR achieved by the UE at the eNB varies linearly with the path loss.

Higher levels of path loss are associated with lower SINR and vice versa:

When the UE is close to the cell center, the pathloss decreases and hence the target SINR is increased.

When the UE is at the cell edge, the pathloss increases and hence the target SINR is decreased.

When the UE is close to the cell centre, target SINR is increased, whereas the target SINR of the UE at the

cell edge is decreased.






6.3.1 SINR Target Computation

For simplification purpose, in order to keep the SIR_Target within a reasonable and realistic range, a paramater PLNominal is introduced:

SIRNew_Target_PUSCH= min{ max {SIR Target_PUSCH_Initial -(1 - pUSCHPowerControlAlphaFactor ) x ( PL – pathLossNominal), minSIRtargetForFractionalPowerCtrl }, maxSIRtargetForFractionalPowerCtrl}

PLNominal is associated to SIR_TargetInitial and is the corresponding PathLoss when SIR_TargetCurrent = SIR_TargetInitial

where

• Parameter pathLossNominal configures the nominal path loss and corresponds to the path loss at which

we want the SINR target to be uplinkSIRtargetValueForDynamicPUSCHscheduling (i.e. the SINR

uplinkSIRtargetValueForDynamicPUSCHscheduling is also the nominal SINR target).

• Parameter maxSIRtargetForFractionalPowerCtrl configures the maximum SINR target.

• Parameter minSIRtargetForFractionalPowerCtrl configures the minimum SINR target so that the end-user experience remains acceptable.

• PLav is an estimate of the average path loss based on the power headroom reports of the UE

Note that when the full path loss compensation is used (i.e. when pUSCHPowerControlAlphaFactor is set

to 1.0), the target SINR is always equal to uplinkSIRtargetValueForDynamicPUSCHscheduling and

parameters pathLossNominal, maxSIRtargetForFractionalPowerCtrl, and

minSIRtargetForFractionalPowerCtrl are ignored.






6.3.1 SINR Target Computation [cont.]

From the following formula

SIR_TargetCurrent = SIR_TargetInitial – ( 1 – αPL ) x PL = SIR_TargetInitial – ( 1 – αPL ) x ( PL – PLNominal )

We can understand the need to adjsut the parameter network p0NominalPUSCH when FPC is introduced:

Consequence of a too low value of p0NominalPUSCH problem to attach to thenetwork at Cell Edge.

Consequence of a too high value of p0NominalPUSCH higher UL interference.

p0NominalPUSCH

SIR_TargetInitial – (1 –αPL )xPL

+( 1– αPL) x PLNominal

Note: p0NominalPUSCH can be approximately computed as:

= -121dBm + 3dB IoT + SIR_Target(PL = RStxpower - qRxLevMin) + (1 – αPL).(RStxpower – qRxLevMin)

For 20MHz, RStxpower = referenceSignalPower = 14dBm, qRxLevMin = -120dBm, αPL = 0.7,

SIR_TargetInitial = 10dB, PLNominal = 100dB, then we would have:

p0NominalPUSCH = -121 + 3 + 0 + 40 = -78dBm






6.3.2 SIR Target Vs UL Pathloss Simulation

SIR_TargetCurrent = SIR_TargetInitial–(1 – αPL) x( UL_PL–PLNominal)InitialSIR=15 dBMaxSIR= 15 dBMinSIR=0dBAlpha α= 0.7






6.3.2 SIR Target Vs UL Pathloss Simulation [cont.]

SIR_TargetCurrent = SIR_TargetInitial–(1 – αPL) x( UL_PL–PLNominal)InitialSIR=15 dBMaxSIR= 15 dBMinSIR=0dBPathloss Nominal= 60dB






6.3.3 Fractional Power related parameters

Parmeter pathLossNominal uplinkSIRtargetValueForDynamicPUSCHscheduling


Range & Unit Integer[0..127] dB

Float[-5..25] step = 0.1 dB


B--Modems+Cells-of-eNB / Optimization - Tuning

Value 60 PUSCHPowerControlAlphaFactor

uplinkSIRtargetValueForDynamicPUSCHscheduling

1.0 4.0

0.8 11.0

0.7 15.0


The higher the SINR target, the higher the near-cell throughput but the higher the interference generated in the different cells of the network (and thus the lower the cell-edge and overall cell throughput).

uplinkSIRtargetValueForDynamicPUSCHscheduling setting This parameter is a key RF optimization parameter.

In the trial mode, the higher the setting of this parameter the higher the throughput, but also, the higher

the setting the higher the interference generated in the neighboring cells. However, as in this mode the

focus is on the target cell performance rather than the overall network performance, this is not an issue.

In this case, the nominal SINR target uplinkSIRtargetValueForDynamicPUSCHscheduling is defaulted to

10.0.






6.3.3 Fractional Power related parameters [cont.]

Parmeter maxSIRtargetForFractionalPowerCtrl

minSIRtargetForFractionalPowerCtrl



Float[-5..25] step = 0.1 dB

Class/Cat B--Cell / Fixed B--Cell / Fixed

Value 15 0.0


The setting of this parameter must satisfy the condition:

maxSIRtargetForFractionalPowerCtrl ≥uplinkSIRtargetValueForDynamicPUSCHscheduling

The setting of this parameter must satisfy the condition:

minSIRtargetForFractionalPowerCtrl ≤uplinkSIRtargetValueForDynamicPUSCHscheduling





7 Link Adaptation





7 Link Adaptation

7.1 Link Adaptation Process

Link adaptation is the process by which the Modulation and Coding Scheme (MCS) used (to transmit data on the scheduled bearer) is adapted to changing radio conditions (or radio link quality) of the UE.

The selected MCS is the one that maximizes the transmission rate for a given targeted BLER.

Link adaptation involves the use of:

Adaptive Modulation and Coding (AMC): attempts to choose the modulation and coding scheme (per codeword) which results in the best throughput for the scheduled user’s current RF condition as influenced by both signal fading and interference variations

Error rate control (BLER control): monitors the actual error rate performance of each user (through ACK/NACK events) and dynamically adjusts the SINR thresholds use in the AMC scheme in order to ensure the desired error rate is achieved

MIMO mode selection: selects spatial multiplexing or transmit diversity in the downlink based on CQI/PMI/RI feedback from the UE

An improvement in the radio link quality causes the transmitter to use a less robust MCS and hence a higher

data transmission rate. Conversely, a degradation in the radio link quality causes the transmitter to use a

more robust MCS and hence a lower data transmission rate.





7 Link Adaptation

7.2 macOuterLoopBlerControlTargetBler (Traffic & Signaling)

Parmeter macOuterLoopBlerControlTargetBler macOuterLoopBlerControlTargetBler



Range & Unit Integer[0..50] %

Integer[0..50] %

Class/Cat B—Cells of eNB / Fixed B—Cells of eNB / Fixed

Value 10 10


[Note that when parameter cqiReportingModeAperiodic is set to “disabled”, the UE reports no CQI. In this

case, the downlink scheduler uses the MCS configured by parameter

rafficRadioBearerConf::macInitialMCSIndexForBearerSetupDl and

SignalingRadioBearerConf::macInitialMCSIndexForBearerSetupDl.]





7 Link Adaptation

7.3 cQIToSINRLookUpTable for DL Operations

At each new TTI, the link adaptation provides each scheduled bearer with a MCS common to all its PRBs.

The link adaptation algorithm converts CQI values into SINR values using a lookup table configured by parameter cQIToSINRLookUpTable.

CQI CQI ~~~SINRFrom

cQIToSINRLookUpTableMCS & TBS Selection

Parameter cQIToSINRLookUpTable


Range & Unit List of 15 Float values [-10..30] step = 0.25 dB


Value [-6.00, -4.00, -2.75, -0.75, 1.25, 2.75, 5.00, 6.75, 8.50,10.75, 12.50, 14.50, 16.25, 17.75, 20.00]


ALU recommends that the operator not change this value

12

PDCCH (MCS & TBS)3

4

PDSCH (MCS & TBS)

5

The link adaptation algorithm converts CQI values into SINR values using a lookup table configured by

parameter cQIToSINRLookUpTable.

These SINR values are used to produce one SINR value that is used to derive the MCS ( SINRMCS ).

Twentynine SINRMCS intervals are defined.

Each of them corresponds to an MCS. The lowest interval corresponds to the most robust MCS (and hence to

the lowest transmission rate). The highest interval corresponds to the least robust MCS (and hence to the

highest transmission rate). The selected MCS is the one that is mapped to the interval SINRMCS falls into.

The intervals do not overlap and the transition from an interval to another is defined by a threshold value.





7 Link Adaptation

7.4 dlMCSTransitionTable

The MCS is derived based on SINRMCS . 29 SINRMCS intervals are defined. Each of them corresponds to an MCS. Parameter dlMCSTransitionTable configures these 28 (MCS) transition thresholds.

Parameter dlMCSTransitionTable


Range & Unit List of 28 Float values: [-10..30] step = 0.25 dB

Class/Cat B--Cells-of-eNB / Optimization - Tuning

This parameter is defaulted to:

[-2.5, -1.75, -1.25, -0.5, 0.5, 1.0, 2.0, 3.0, 3.75, 4.75, 5.0, 6.0, 7.0, 7.5, 8.5, 9.0, 10.25, 11.5, 11.75, 12.75, 13.5, 14.25, 15.5, 16.25, 17, 17.75, 19.0, 0.0].


Higher threshold values will result in lower data rates. Lower values will lead to more optimistic MCS assignments and hence, more HARQ retransmissions and higher BLERs.

dlMCSTransitionTable(1)

dlMCSTransitionTable(2)dlMCSTransitionTable(3)



MCS0 MCS1 MCS2 MCS27 MCS28

SINR (MCS)

The lowest interval corresponds to the most robust MCS (and hence to the lowest transmission rate). The

highest interval corresponds to the least robust MCS (and hence to the highest transmission rate).

The selected MCS is the one that is mapped to the interval SINRMCS falls into.The intervals do not overlap and the transition from an interval to another is defined by a threshold value.





7 Link Adaptation

7.4 dlMCSTransitionTable [cont.]

Parameter macSINROffsetForLinkAdaptation macSINROffsetForLinkAdaptationObject ENBEquipment/Enb/DedicatedConf/




Float[-20..20] step = 0.25 dB

Class/Cat B--Cells-of-eNB / Fixed B--Cells-of-eNB / Fixed

Value 0.0 0.0

SINROffset represents a power offset used to support different BLER targets depending on the bearer type.

It is configured by either TrafficRadioBearerConf::macSINROffsetForLinkAdaptationDl or

SignalingRadioBearerConf::macSINROffsetForLinkAdaptationDl

(depending on whether it is a data radio bearer or signaling dedicated radio bearer).





7 Link Adaptation

7.5 Bloc Error Rate Loop Control

Control adaptively the link adaptation by introducing an ACK-NACK dependant power offset, in order to force the link adaptation to meet initial BLER target recommendation

Initial BLER estimation based on ACK/NACK first transmissionLow pass filtering BLER estimation Power offset calculation based on gap between the estimated first transmission BLER and the initial BLER target

One shot power offset estimation : correction range [-3,+3] dBOne procedure by bearerOne procedure by code word

CQI & ACK/NACK

FromcQIToSINRLookUpTable

MCS & TBS SelectionCQI ~~~SINR

ACK/NACKBLER Estimation

when the BLER estimation is too high (or too low) compared to

the SIR target (10%)

+/-dB

Performances of the adaptive modulation and coding functionality is upper limited by the CQI feedback

compared to the real radio channel quality. The purpose of the Bler control loop is to adaptively control

link adaptation by introducing an ACK/NACK dependent power offset.





7 Link Adaptation

7.6 Modulation TBS index for DL MCS

The Transport Block Size (TBS) is derived from Table 32 based on ITBS (mapped from the MCS) and NPRB (number of PBs used for the transmission of the Transport block in question).

Note that MCSs 9 and 10 give the same TBS (since they are mapped to the same value of ITBS).

Similarly, MCSs 16 and 17 give the same TBS, rate matching.

MCSs 29, 30, 31 indicate to use the previous MCS received in PDCCH (MCS 29 for the previous QPSK-based

MCS, MCS 30 for the previous 16-QAM based MCS and MCS 31 for the previous 64-QAM-based MCS), which

can be used when a Transport Block is repeated. In LA3.0, MCSs 29, 30, 31 are not supported.

Also, in LA3.0, MCS 28 is not supported.





7 Link Adaptation

7.7 SINR-to-MCS Look Up Table for UL Operations

The MCS is derived using a hardcoded SINR-to-MCS look up table The lookup table outputs the MCS scheme i.e.

The selected modulation: {QPSK, 16QAM}The selected coding scheme: Choices available are

{1/3; ½; 2/3; ¾} for QPSK, {1/2; 2/3; 3/4;7/8} for 16QAM SIMO {1/2; 2/3;3/4} for 16QAM MU-MIMO

CQI

SRS ~~~SINRFrom

SINR-to-MCS Look Up Table MCS & TBS Selection

12

PDCCH (MCS & TBS)3

4

PUSCH (MCS & TBS)

5

Like in DL, the MCS selection is based on a lookup table, but the UL radio conditions are estimated on the

SRS reception and not CQI.

The Sounding Reference Signal (SRS) is measured by the eNodeB to estimate the UL radio condition.





7 Link Adaptation

7.8 Modulation TBS index for UL MCS

Note that MCSs 10 and 11 give the same TBS (since they are mapped to the same value of ITBS).

Similarly, MCSs 20 and 21 give the same TBS.





8 H-ARQ





8 H-ARQ

8.1 H-ARQ Principle

Two major techniques are used to combat the effects of channel errors, Forward Error Control (FEC) techniques and Automatic Repeat Request (ARQ) techniques.

The FEC technique consumes bandwidth irrespective of the “goodness” of the channel

while the ARQ technique consumes bandwidth only when the channel is “bad”.

The FEC is quite faster to correct errors than the ARQ.

The combination of these two techniques has led to what is called the Hybrid ARQ (HARQ) mechanism.The Hybrid ARQ protocol is part of the MAC layer, while the soft-combining operation

is handled by the physical layer.

1 2 2 3

1 2 2 3

1 2 3

Error Error

Nack Time

Time

TimeStop and Wait H- ARQ

Fast hybrid ARQ with soft combining is used in LTE to allow the terminal to rapidly request

retransmissions of erroneously received transport blocks and to provide atool for implicit rate adaptation.

Retransmissions can be rapidly requested after each packet transmission, thereby minimizing the impact

on end-user performance from erroneously received packets. Incremental redundancy is used as the soft

combining strategy and the receiver buffers the soft bits to be able to do soft combining between

transmission attempts. The underlying protocol is that of a multiple parallel stop-and-wait hybrid ARQ

Processes:

Upon reception of a transport block, the receiver makes an attempt to decode the transport block and

informs the transmitter about the outcome of the decoding operation through a single ACK/NACK bit

indicating whether the decoding was successful or if a retransmission of the transport block is required.





8 H-ARQ

8.2 H-ARQ Process in UL & DL

The H-ARQ process runs in the eNodeB and in the UE.

PDSCH (PacketTransmission)

PUCCH (NACK)

PDSCH Re-Tx (H-ARQ)

PUCCH (ACK)

PUSCH (PacketTransmission)

PHICH (NACK)

PUSCH Re-Tx (H-ARQ)

PHICH (ACK)

H-ARQ Process in UL H-ARQ Process in DL

In the downlink, the ACK/NACK is received on the PUCCH assigned to the UE for a transmission on the PDSCH.There is one HARQ entity at the UE which maintains a number of parallel HARQ processes. Each HARQ process is associated with a HARQ process identifier. The maximum number of DL HARQ processes is 8 for FDD and 4, 6, 7, 9, 10, 12 or 15 for TDD depending on the UL/DL configuration.The HARQ entity directs HARQ information and associated TBs received on the DLSCH to the corresponding HARQ processes.When the physical layer is configured for spatial multiplexing, one or two Transport Blocks are expected per subframe. Otherwise, one Transport Block is expected per subframe.

In the uplink, the ACK/NACK is received on the PHICH for a transmission on the PUSCH.There is one HARQ entity at the UE, which maintains a number of parallel HARQ processes. The maximum number of UL HARQ processes is 8 for FDD and 1, 2, 3, 4, 6 or 7 for TDD depending on the UL/DL configuration.Each HARQ process is associated with a HARQ buffer. Each HARQ process maintains a state variable which indicates the number of transmissions that have taken place for the MAC PDU currently in the buffer. This variable is initialized to 0 when a new transmission is requested and incremented with each retransmission.The sequence of redundancy versions is 0, 2, 3, 1. The corresponding variable is set to 0 when a new transmission is initialized and updated modulo 4 with each retransmission.For a new transmission, the HARQ process delivers the MAC PDU, the uplink grant and the HARQ information to the identified HARQ process, and then instructs the identified HARQ process to trigger a new transmission. There is one HARQ entity in the UE as well as the eNB per UE context.For a retransmission, the HARQ process delivers the uplink grant and the HARQ information (redundancy version) to the identified HARQ process, and then instructs the identified HARQ process to generate a retransmission.






8.2.1 PDSCH H-ARQ Timing

There is one H-ARQ entity at UE which processes the HARQ process identifiers indicated by the HARQ information associated with TBs received on the DLSCH.8 parallel HARQ processes are used in the UE to support the H-ARQ entity.

PDSCH PDSCH

PUCCH

PUCCH

PDSCHPDSCH

8 subframes

UE DL Rx Processing(= 3TTI-2Tp)

eNB DL Tx Processing (=3TTI)

eNB Rx

eNB Tx

Ue Rx

Ue Tx

2Tp

Tp

SF#N SF#N+1 SF#N+2 SF#N+3 SF#N+4 SF#N+5 SF#N+6 SF#N+7 SF#N+8 SF#N+9

Tp: Propagartion delay

UE DL Rx processing tie: 3TTI – 2 Tp

eNB DL Tx processing time: 3TTI






8.2.2 PUSCH H-ARQ Timing

There is one HARQ entity at the UE. A number of parallel HARQ processes are used in the UE to support the HARQ entity, allowing transmissions to take place continuously while waiting for the feedback on the successful or unsuccessful reception of previous transmissions.At a given TTI, if an uplink grant is valid for the TTI, the HARQ entity identifies the HARQ process for which a transmission should take place.It also routes the receiver feedback (ACK/NACK information) relayed by the physical layer, to the appropriate HARQ process.

PUSCH

PDCCH

PUSCH

8 subframes

UE UL Tx Processing(= 4TTI-2Tp-(1-3 symbols))

eNB UL Rx Processing (=3TTI)

eNB Rx

eNB Tx

Ue Rx

Ue Tx

2Tp

Tp

SF#N SF#N+1 SF#N+2 SF#N+3 SF#N+4 SF#N+5 SF#N+6 SF#N+7 SF#N+8 SF#N+9

PUSCH

PUSCH

PDCCH

1-3 symbols

The number of HARQ processes is equal to 8. Each process is associated with a number from 0 to 7






8.2.3 H-ARQ Related Parameters

Parameter macHARQMaxNumberOfTransmissionDl

macHARQMaxTimerDl

macHARQMaxNumberOfTransmissionDl

macHARQMaxTimerDl



Range & Unit

Integer [1..8] Integer [1..500] ms Integer [1..8] Integer [1..500] ms

Class/Cat B--Cells-of-eNB / Fixed

Value

QCI

8 94

1 2 32

2 4 62

3 4 62

4 4 62

5 4 62

6 4 62

7 4 62

8 4 62

9 4 62











End of ModuleRadio Ressources Management





Module 3Session Management

Issue

Section 1





· 9400 LTE LA3.0 Radio Algorithms and Parameters description· Session Management1 · 3 · 2

Blank Page




Document History





Module Objectives


Describe the LA3.0 Radio parameters description and some engineering recommendations related to :

The Random Access procedure and the associated parametersThe RRC Connection procedure and the associated parametersThe Admission control and the paging mechanism and the associated parameters











Table of Contents


1 Cell Setup 71.1 Self Organizing Network (SON) 8

1.1.1 Automatic Neighbor relation (ANR) 91.1.2 Automatic Allocation of PCI: PCI 10

1.1.2.1 Automatic Allocation of PCI: PCI Parameters 121.1.3 Automatic Configuration of PCI Algorithms 13

1.1.3.1 Centralized PCI Allocation:Provisioning 141.1.3.2 Centralized PCI Allocation: Algorithm 161.1.3.3 Centralized PCI Allocation: PCI Auto Correction 171.1.3.4 Centralized PCI Allocation: PCI Auto Detection 18

1.1.4 Distributed PCI Allocation Algorithm 191.1.4.1 :eNB inputs 201.1.4.2 Collision & Conflict Resolution 21

Example 231.1.4.3 Maintenance Period 24

2 Random Access Procedure 252.1 Random Access Procedure 26

2.1.1 PRACH Configuration 282.1.1.1 Random Access Preamble 29

2.2 Random Access Procedure Related Parameters 302.3 Random Access Response: Message2 32

2.3.1 raResponseWindowSize 332.3.2 Message 2 & SRB0 Scheduling 34

2.4 UL Transmission: Message 3 352.4.1 Message 3 Scheduling 362.4.2 maxHARQmsg3Tx Parameter 37

2.5 Contention Resolution: Message 4 382.5.1 Message 4 Related Parameters 39

2.6 Random Access Failure 402.7 RACH Power Control 41

3 RRC Connection Management 423.1 Random Access Procedure 433.2 RRC Connection Establishement 443.3 RRC Connection Establishement Failures 46

3.3.1 Timers Parameters 484 UE EUTRAN Attach 49

4.1 UE EUTRAN Attach 504.2 S1-Setup 514.3 S1-Setup Failure 52

4.3.1 s1APProcedureDefenceTimer Parameter 544.4 Bearer Management 554.4 QoS Parameters 57

4.4.1 ALU QoS Templates 584.5 eRAB Establishement 59

5 Admission Control 605.1 Radio Admission Control 615.2 Admission Decision 63

6 Paging 676.1 Paging Channels 68

6.1.1 Paging Occasion Determination 696.1.1.1 Paging Related Parameters 716.1.1.2 Discontinuous Reception (DRX) Forced Mode 72













1 Cell Setup





1 Cell Setup

1.1 Self Organizing Network (SON)

SON domain has been brought into 3GPP specifications in R8, which is the first release that considers LTE.Aim of SON is to allow automation of configuration procedures, optimization processes and adaptation to network changes (new deployment, failures in surrounding eNB/cells)Reduce manual intervention needed in these operations and increase the reactivity of the system.SON features are being introduced progressively in Alcatel-Lucent LTE Solution:

Full support of ANR.Centralized and distributed PCI allocation.

Planning Deployement Optimization Maintenance

SON’s self configuration functions reduce CAPEX

SON’s self optimization and energy-saving

functions reduce CAPEX

SON’s self optimization and Self-healing functions

improve user experience

The Self Organizing Network (SON) introduced as part of the 3GPP Long Term Evolution (LTE) is a key driver

for improving O&M. It aims at reducing the cost of installation and management by simplifying operational

tasks through automated mechanisms such as self-configuration and self-optimization. While supporting

3GPP standard on LTE/SON, NEC’s hybrid management architecture will enhance robustness, scalability and

response of self-X functions and enable effective integration into the existing operations. Moreover, SON

will enhance user perceived qualities by optimizing intra-cell radio qualities with a radio planning tool.






1.1.1 Automatic Neighbor relation (ANR)

Automatic Neighbor Relation feature helps to avoid (or reduce) manualconfiguration of the neighboring relationships during network introduction and builtout of the network configuration.

ANR relies on various types of data received and processed by theeNB (configuration parameters, radio measurements performed by UEs, X2Messages

It provides full automatic neighboring configuration: autonomous acquisition of all neighbor cell identifiers (PCI, ECGI, TAC) and associated transport information (IP address) to establish X2 link to the serving eNB.

It is able to add or remove neighbor relations to adapt the eNBconfiguration to network evolution (addition of eNB in its vicinity, radio parameter tuning that affects neighbor cells coverage)







1.1.2 Automatic Allocation of PCI: PCI

Each Cell in eUTRAN will be known through two different identifiers:

ECGI (E-UTRAN Cell Global Identifier): The Global Cell Identity (ECGI) is a cell identifier unique in the world. It has a global scope, and is used for cell identification purposes with MME, with another eNB, etc.

PCI (Physical Cell Identifier): differs from the Global Cell Identity in that it has a Local scope, and is only used for identification purposes between UE and eNB.

Physical layerCell identity(1 out of 504)

PSS

SSS

12

13

1

13

2

31

2

13

21

12

3

222

3 3 3

Physical Layer cell identity

Physical Layer cell identity

The Physical Cell Identifier or PCI is the identity of the cell as it appears on the radio to a UE

The physical cell identity is used, among other things, to identify a cell in interactions

between eNB and UE, in particular measurement configuration and Reporting.

A physical cell identity must be unique within a given region and for a given frequency to avoid any

collision or confusion.







1.1.2 Automatic Allocation of PCI: PCI [cont.]

The automatic allocation of PCI to a particular cell aims to avoid the PCI collision, the PCI confusion.

PCI Collision: occurs when in a given location; the signals from two different cells radiating the same PCI can be received by a UE. (Two neighbors cells share the same PCI).

PCI Confusion: appears when a given cell, knowingly or unknowingly, has two neighbors sharing the same PCI.

Confusion area

A PCI collision occurs when in a given location; the signals from two different cells radiating the same PCI

can be received by a UE.

In the worst situation, a UE may be unable to access either of the two cells due to the interference

generated. At best, a UE will be able to access one of the cells but will be highly interfered.

Since the UE uses the PCI to identify the cell on which it reports measurements.

this will cause confusion in the eNB, as it will not know which of the two cells the report relates to. In the

best case, the eNB knows of the two cells and will ask the UE to report the CGI before triggering a

handover.

In the worst case, the eNB knows of only one cell and will trigger a handover to that cell, whereas the UE

may have been reporting the other cell. This may lead to a high number of handover failures and/or call

drops.






1.1.2 Automatic Allocation of PCI: PCI

1.1.2.1 Automatic Allocation of PCI: PCI Parameters

Parameter physicalLayerCellIdentityGroupIndex

physicalLayerCellIdentityIndex

relativeCellIdentity

Object ENBEquipment/Enb/LteCell

Range & Unit

Integer[0..167]

Integer[0..2]

Integer0 to 255, Step 1

Class/CatB--Cell / I&C OMC B--Modem+Cell(s) /

I&C OMC

Value we can count on 504 unique cell identities (168 cell identity groups with 3 cell identities in each group).

O.D (set by the operator)

Each Physical cell Identity corresponding to a unique combination of one orthogonal sequence and one

pseudo-random sequence, we can count on 504 unique cell identities (168 cell identity groups with 3 cell

identities in each group).

The Physical cell ID can be computed with the following formula:

PCI=physicalLayerCellIdentityIndex + 3 x physicalLayerCellIdentityGroupIndex







1.1.3 Automatic Configuration of PCI Algorithms

3GPP specifies three solutions for automatic configuration of the PCI:

Centralized solution: all the mechanism and algorithms are implemented inOAM system (for instance in SAM/WPS). SAM/WPS is then in charge for the PCI allocation.

Distributed solution is implemented within the eNB. The automatic PCI allocation is managed by the eNB. (Introduced in LA3.0)

Hybrid solution is mixing the centralized solution with the distributed one.

Note that in Alcatel-Lucent LA3.0. solution, the Centralized and Distributed algorithms are implemented for the Automatic configuration of the PCI (SAM/WPS is in charge for the PCI allocation).

SONSelf Optimizing Network concept

Centralized(XMS/WPS)

Hybrid Solution(XMS/eNB)

Distributed(eNB)

In order to minimize the provisioning during the deployment of LTE Networks, 3GPP specified algorithms

allowing eUTRAN network to be able to automate the configuration of some network parameters. These

algorithms are part of Self Optimizing Network concept (SON).

One of the parameters that can be automatically configured is the Physical Cell ID (PCI).

The eUTRAN system automatically assigns a PCI for each of its supported cells, ensuring that each ID is

unique when compared against itself neighbor cells and neighbors’ neighbor cells.

3GPP (TS 32.500) is specifying three solutions for automatic configuration of the Physical Cell ID:

•







1.1.3.1 Centralized PCI Allocation:Provisioning

PCI Provisioning algorithm is integrated in WPS cell creation wizardIts objective is to allocate each cell the first PCI found in the list of available PCIs that is

not already used by another cell having the same frequency and located closer than a configurable secure distance (called Secured Radius).

WPS Configuration Tool PCI#

PCI#

PCI#

PCI#

PCI#

PCI#

PCI#

PCI#

PCI#

PCI#

PCI#

PCI#

PCI#

PC#

PCI#

PCI#

PCI#

PCI#

PCI#

PCI#PCI#

PCI#

PCI#

PCI#

PCI#

PCI#

PCI#

PC# PCI#

PCI#

PCI#

PCI#

PCI#

PCI#PCI#

Secure Radius

Available PCI ListPCI# freePCI# freePCI# AllocatedPCI# freePCI#AllocatedPCI#AllocatedPCI# freePCI#FreePCI#FreePCI#Free







1.1.3.1 Centralized PCI Allocation:Provisioning [cont.]

PCI Provisioning Algorithm This algorithm is based on a specific set of the following configurable parameters:

Geographical coordinates (lteCellPositionLongitude & lteCellPositionLatitude):used to compute the distance from the current cell to each of its neighbors.

Cell Frequency: algorithm being executed only on cells using the same freq.cellRadius: parameter used to identify the cell coverage and define the default value

of Secured Radius that can guarantee collision free and confusion free condition. It is used to compute the default value of SecuredRadiusSecuredRadius is a WPS internal parameter that can be accessed by the customer

during the PCI configuration operation via the PCI configuration wizard. SecuredRadius = N * cellRadius

with N ≥ 3 (The default value of SecuredRadius is computed based on a N = 4)List of PCI allowed: The PCI list is a set of PCI that the operator can pre-define at eNB

level and use to allocate the PCI.

Engineering Recommendation: SecuredRadius

Even if SecuredRadius (computed in km) is modifiable by the operator (within PCI configuration wizard in

WPS), it is highly recommended to keep the default value (implying N = 4).

In case securedRadius need to be changed (due to customer and/or geographical constraints), it must be

done carefully as it can have the following negative effects:

- a too low securedRadius will increase drastically the risk of PCI collision and confusion; on the other hand

- a too high securedRadius will increase the risk to have no free PCI available.

SecureRadius vs. cellRadius configuration

The SecureRadius value can be directly modified in the WMS PCI Configuration wizard, or indirectly through

the cellRadius value.

If SecureRadius need to be modified (to increase PCI algorithm precision), it is highly recommended to

directly change its value in the PCI Configuration wizard.

As it interacts with other features, the modification of cellRadius is not advisable.







1.1.3.2 Centralized PCI Allocation: Algorithm

- pciListTobeUsed = pciAllowedList- sort pciListTobeUsed

pciListTobeUsed

Remove from pciListToBeUsed the PCI of the cellsfor which lteCellA has a neighbour relation.neighbour relation with lteCellA

geographicalDistance(lteCellA, lteCell_j)< secured

Radius

pciListToBeUsed empty ?

Search the first PCI in pciListTobeUsedrespecting the rule PCI MOD 6 or PCI MOD 3

Display an error messageto the operator. No enough

PCI in pciAllowedList

Does PCI exist

Display an error message to theoperator. No PCI respecting therule PCI MOD 6. Increase thelist or set manually the PCI

lteCellA is selected

YesNo

No

Yes

Remove PCI of lteCell_jFrom pciListTobeUsed

Allocate the PCIto lteCellA

No Yes

For each lteCell_j of the network having the samefrequency (dlEARFCN) as lteCellA :- compute geographicalDistance(lteCellA, lteCell_j)

Each time a new cell (LteCellA) is created on an eNB (with the above mentioned mandatory parameters

correctly set and the PCI not set), the PCI allocation/provisioning algorithm is run.







1.1.3.3 Centralized PCI Allocation: PCI Auto Correction

The algorithm for auto corrective PCI consists in checking then fixing all the potential PCI collisions and PCI confusion.

The algorithm is implemented in WPS and is running according to the existing neighbour relations.

Following elements are taken into account by the PCI auto-correction algorithm:

1.ECGI composed of macroEnbId, relativeCellIdentity and PLMN Identity.2.PCI composed of physicalLayerCellIdentityGroupIndex and

physicalLayerCellIdentityIndex3.List of PCI allowed

PCI Auto Correction has the capability to detect and fix the PCI conflicts on theentire network contrary to the algorithm for PCI provisioning which is fixing the

conflict only per eNB.

This auto corrective algorithm is taking advantage of the fact that the different lteNeighboringCellRelation

of each LteCell contain all the information needed to know the PCI used by the served cell and also the

neighbour cells.

The geographical coordinates are not used by the algorithm (for performance reasons).







1.1.3.4 Centralized PCI Allocation: PCI Auto Detection

For each lteCell of eNB- collect (ECGI, PCI) of its local cells- collect (ECGI, PCI) of its neighbour cells

Search the first PCI in pciAllowedListcompliant to:- Unique around the local and neighbour cells- Rule PCI MOD 6

Check the uniqueness of PCI of lteCell around itslocal and neighbour cells.Collect (ECGI, PCI) of lteCell having the same PCI

go to the next lteCell

Does PCI exist in thepciAllowedList?

Display an error message to the operator

Check is OKAmong the lteCell having the samePCI, select the one having theminimum of neighbour relation

Allocate the PCI to lteCEll

Is lteCell has aneighbour relation?

Is PCI lteCell alreadyused?

YesNo

Yes

YesNo

No

The algorithm is selecting each LteCell of the network and is comparing it with its neighbour cells. If the

PCI of LteCell is already used by one of its neighbour cells, the algorithm is identifying the cell having the

lower number of neighbouring relations then provides it a new PCI by respecting the following conditions:

- New PCI must belong to pciAllowedList defined by the operator.

- New PCI must be unique around of the neighbour cells and the neighbour neighbour’s cells.

- New PCI must respect the rule (“PCI MOD 6/MOD 3”)







1.1.4 Distributed PCI Allocation Algorithm

In Release LA3.0, a distributed algorithm for PCI allocation is introduced in connection with the Automatic Neighbor Relation (ANR) Feature. The distributed PCI allocation feature is directly associated with the ANR

Feature, as a result, it can only be enabled if the ANR feature is enabled (a WPS check enforces this relationship) by setting the value of parameter anrEnable to “True”.

isSonPciAllocationEnabled :This flag combined to anrEnable attribute, allows the activation and the deactivation of PCI allocation by eNodeB.

Parameter isSonPciAllocationEnabledObject ENBEquipment/Enb/ActivationServiceRange & Unit Boolean [false; true]

Class/Cat C--Immediate-propagation/ Optimization - Selection

Value TRUE

Enabling ANR feature is a pre-requisite for PCI allocation by eNodeB.






1.1.4.1 :eNB inputs

Distributed allocation is made using different kinds of inputs:

ANR function: ANR measurement report PCI values that are (detected” by the UEs in the neighboring cells of the eNB.

X2 served cells information: eNBs exchange information about the cells they serve, and in particular, the PCIs they use. So an eNB is capable of knowing which PCIs are in use by neighboring eNBs

X2 Neighbor information: Two eNBs can also share information about their neighbors.

This way, an eNB can know the PCIs of the neighbors of its neighbos.

These mechanisms combined allow an eNB to allocate PCI values and to detect and repair PCI collisions and confusions






1.1.4.2 Collision & Conflict Resolution

In the eNB, PCI allocation is performed if a cell does not have a configured value during it’s strat up.

Conflict and confusion detection is triggered each time any information about PCI values allocated to neighbor cells is updated (received over X2)

If conflict existethen, the operator is warned.

If the conflict can be solved though an update of a local PCI, the update is performed during maintenance period.

To avoid simultanious resolution attempts by 2 peer eNs, random timers are started before the update is actually made.

The first eNB that succeeds in changing the PCI value sends the information to the other eNB, and it will abort its resolution attempt







1.1.4.2 Collision & Conflict Resolution [cont.]

PCI conflicts (collision and confusion) that are detected by the distributed PCI

allocation algorithm are corrected during a maintenance period.

The following general rules are used:

Correction of PCI conflict is regarded as a higher priority than correction of PCI confusion.

If a newly commissioned eNB chooses a PCI that causes a collision or confusion, then it rather than the previously-existing eNB, will attempt to find a conflict-free PCI.

Default: 2C--New-set-ups / Fixed

Integer, h (hour) [1..24] step = 1

maintenancePeriodStartTimeParameter enableMaintenancePeriod

Object ENBEquipment/Enb/SelfOrganizingNetwork/AutomaticPhysicalCellIdentity

Range & Unit Boolean [false; true]

Class/Cat C--New-set-ups / Fixed

Value Default: True

The use of the maintenance period can be enabled or disabled with the enableMaintenancePeriod

parameter.

Typically, if the isSonPciAllocationEnabled value is “True”, then the value of the enableMaintenancePeriod

parameter should be “True”

enableMaintenancePeriod : This parameter allows the operator to disable the maintenance period for PCI

conflict correction if needed. By default, the maintenace period is enabled.





1.1.4.2 Collision & Conflict Resolution

Example

A new eNB “B”chooses a timer value in the range of 0-15 minutesA mature eNB “A” in this example chooses a timer value in the range of

16-60 minutes

Timer A

Timer B

eNB A

eNB B

Conflictdetection

ConflictResolution by eNB A

Update sent over X2







1.1.4.3 Maintenance Period

The eNB maintenance period happens once a day and is used by the automatic PCI

feature to solve potential PCI confusion situations.

The eNB maintenance period begins This will happen when:

current time is equal to maintenancePeriodStartTime &“enableMaintenancePeriod parameter” is set to ‘true’.

maintenancePeriodStartTime: determines the time of day, during which the eNB will begin trying to clear conflict and confusion situations.

Parameter maintenancePeriodStartTimeObject ENBEquipment/Enb/SelfOrganizingNetwork

/AutomaticPhysicalCellIdentity

Range & Unit Integer, h (hour) [1..24] step = 1Class/Cat C--New-set-ups / Fixed

Value Default: 2

When the maintenance period (by default, 2 hours) begins, the eNB will:

1. For each cell it serves, look for detected PCI confusion situations the cell isvinvolved in.

2. If there is at least one confusion existing (please note that conflict conditions are treated even if a critical alarm has been raised to request manual intervention to solve

the issue):

a. If the cell is new, start a timer which duration is randomly chosen between 0 and 15 minutes

b. If the cell is mature, start a timer which duration is randomly chosen between 16 and 60 minutes






2 Random Access Procedure







2.1 Random Access Procedure

The random access procedure is performed for the following five events:Initial access from RRC_IDLE RRC Connection Re-establishment procedure (after radio link failure).After handover, in the target cell.DL data arrival during RRC_CONNECTED (requiring random access procedure, e.g. when

UL synchronization status is “nonsynchronized”)UL data arrival during RRC_CONNECTED (requiring random access procedure, e.g. when

there are no PUCCH resources for Scheduling Request available)

• Parameter contentionFreeRACHenabled enables/disables the contention freerandom access procedure.

Parameter contentionFreeRACHenabled

Object ENBEquipment/Enb/LteCell/CellRachConfRange & Unit Boolean True/False


Value True

Note that for the last 3 events the UE already has a Cell-Radio Network Temporary Identifier (C-RNTI) while

in the first 2 events the UE does not already have a C-RNTI.

In the case of the handover event, the C-RNTI of the UE is allocated to it in the Handover Command.

Furthermore, the random access procedure takes two distinct forms:

• Contention based, applicable to all five events.

• Non-contention based, applicable only to handover and DL data arrival. Note that both events, the UE

already has a C-RNTI.







2.1 Random Access Procedure [cont.]





PRACH

PUSCH (RRC Connection Request)

PDCCH (RA-RNTI,TA, RA Preamble)

PDSCH (UE Contention Resolution identity)

1

2

3

4

• Message 1: This message contains the random access preamble. It is randomly selected from a set of Random Access Preambles the number of which is configured by parameter numberOfRAPreambles.Once message 1 is transmitted, the UE starts monitoring the PDCCH for Random Access Response • Message 2 (Random Access Response): This message is generated by MAC on DL-SCH and intended for a variable number of UEs.It conveys a Random Access preamble identifier, assignment of Temporary C-RNTI, as well as timing advance information and initial grant for the transmission of message 3.It is addressed to RA-RNTI on PDCCH and does not use HARQ.• Message 3 (First scheduled UL transmission on UL-SCH):For users that do not already have a C-RNTI, this message conveys either the RRC Connection Request (for initial access from RRC_IDLE) or the RRC Connection Re-establishment Request (after radio link failure). After the first transmission of message 3, the UE starts the mac-contention resolution timer. This timer is restarted after each HARQ retransmission of message 3.• Message 4 (Contention Resolution on DL-SCH): This message contains a UE Contention Resolution identity.It is addressed on PDCCH either to the C-RNTI (for UEs that already have one) or to the Temporary C-RNTI (for UEs that do not already have a CRNTI).







2.1.1 PRACH Configuration

The starting subframe number for PRACH RACHMsg1SubFrameNumber is derived from the setting of parameter physicalLayerCellIdentityIndex.

In the frequency domain, PRACH occupies 6 PRBs starting from the PRB configured by parameter prachFrequencyOffset.

physicalLayerCellIdentityIndex RACHMsg1SubFrameNumber0 11 42 7

Parameter prachFrequencyOffset


Range & Unit Integer [0..94] PRBs


Value n25-5MHz 2

n50-10MHz 3

n100-20MHz 4






2.1.1 PRACH Configuration

2.1.1.1 Random Access Preamble

The random access preamble, consists of a cyclic prefix of length TCP and a sequence part of lengthTSEQ .

Values of TCP and TSEQ depend on the preamble format.

There are 64 preambles available in each cell. This index is broadcast as part of System Information.

SequenceCP

TSEQTCP

Preamble format TCP TSEQ

Preamble transmissionwindow duration

Maximum cellradius

0 3168⋅Ts 24576 ⋅Ts 1 subframe 14.53 km

1 21024 ⋅Ts 24576 ⋅Ts 2 subframes 77.34 km

2 6240 ⋅Ts 2 24576 ⋅Ts 2 subframes 29.53 km

321024 ⋅Ts 2 ⋅ 24576 ⋅Ts 3 subframes 100.16 km

The set of 64 preamble sequences in a

cell is found by including first, in the order of increasing cyclic shift, all the available cyclic

shifts of a root Zadoff-Chu sequence with the logical index v =rootSequenceIndex.







2.2 Random Access Procedure Related Parameters





PRACH


PDCCH (RA-RNTI,TA, RA Preamble)

PDSCH (UE Contention Resolution identity)

preambleTransMax

maximumNumberOfDLTransmisionsRACHMessage4

maxHARQmsg3TxNack

Nack

Nack

numberOfRAPreambles







2.2 Random Access Procedure Related Parameters [cont.]

Parameter numberOfRAPreambles

maxHARQmsg3Tx maximumNumberOfDLTransmisionsRACHMessage4

macContentionResolutionTimer


ENBEquipment/Enb/LteCell/CellRachConf/CellRachConfFDD


Range & Unit

Integer[56..64] step = 4

Integer[1..8]

Integer[1..8]

Enumerate{ sf8(0), sf16(1), sf24(2), sf32(3), sf40(4), sf48(5), sf56(6), sf64(7)}

Class/CatB--Cell / Fixed C--Immediate-

propagation / Fixed

Value 56 3 8 sf64







2.3 Random Access Response: Message2

RACH message 2 is sent to the UE within a time window (named the RA Responsewindow and configured by parameter raResponseWindowSize) after the transmission of RACH message1.

This time window starts at subfame (N + 3) where N is the subframe where the end of the preamble transmission occurred.

BW #

5M

hz

SF#0 SF#1 SF#2 SF#3 SF#4 SF#5 SF#6

RA Response window

PDCC

H M

essa

ge(2

)

DL

BW #

5M

hz

PRACH(Preamble)

SF#0 SF#1 SF#2 SF#3 SF#4 SF#5 SF#6UL

DL-SCH

If no Random Access Response is received within the RA Response window, or if none of all received

Random Access Responses contains a Random Access Preamble identifier corresponding to the transmitted

Random Access Preamble, the Random Access Response reception is considered not successful.







2.3.1 raResponseWindowSize

Parameter raResponseWindowSizeObject ENBEquipment/Enb/LteCell/CellRachConfRange & Unit Enumerate

{ sf2(0), sf3(1), sf4(2), sf5(3), sf6(4), sf7(5), sf8(6), sf10(7)}


Value Sf3 (3 subframes)







2.3.2 Message 2 & SRB0 Scheduling

RACH message 2 is scheduled in the following RBGs:With a 5 MHz bandwidth: RBGs 11 and 12 (RBs 22, 23 and 24).With a 10 MHz bandwidth: RBG 0 (RBs 0, 1 and 2).With a 20 MHz bandwidth: RBG 0 (RBs 0, 1, 2 and 3).

SRB0 is scheduled in 18 RBs in the subframe the number of which Is configured by parameter cCCHSRB0SubFrameNumber.

Parameter rachMsg2ForceMCSmin cCCHSRB0SubFrameNumber

Object ENBEquipment/Enb/LteCell/CellRachConfRange & Unit Integer [-1..9] Integer [0..9]


Value 1 8

Parameter rachMsg2ForceMCSmin configures the index of the least robust MCS used for the transmission of

RACH message 2. The range is 0-9 since QPSK is mandatory.








2.4 UL Transmission: Message 3

For users that do not already have a C-RNTI, this message conveys either the RRC Connection Request (for initial access from RRC_IDLE) or the RRC Connection Re-establishment Request (after radio link failure).

This message uses HARQ. Parameter maxHARQmsg3Tx configures the maximum number of attempts for this message.

Scheduled TransmissionmaxHARQmsg3Tx

Nack

Msg3 1st Tx

Nack

Msg3 2nd Tx

Nack

Msg3 xth Tx

After the first transmission of Msg 3, the UE starts the mac-contention resolution timer.

This timer is restarted after each HARQ retransmission of Msg 3.

After the first transmission of message 3, the UE starts the mac-contention resolution timer.

This timer is restarted after each HARQ retransmission of message 3.

After the (re)transmission of message 3, the UE monitors the PDCCH for a PDCCH transmission (message 4),

identified by either C-RNTI (for UEs that already have a C-RNTI) or Temporary C-RNTI (for UEs that do not

already have a C-RNTI).







2.4.1 Message 3 Scheduling

Parameter rACHMessage3StartingPRBIndex


Range & Unit

Integer [0..99]


Value If the system is not operating in the 700 MHzrACHMessage3StartingPRBIndex must be set in the range[pucchPRBsize/2… NUL

RB - pucchPRBsize/2 - rACHMessage3NumberOfPRBs]

Parameter rACHMessage3NumberOfPRBs rACHMessage3MCSIndex

Object ENBEquipment/Enb/LteCell/CellRachConf/CellRachConfFDD


Range & Unit Integer [1..4] Integer [0..4]


Value 2 3

The static scheduler only reserves resources and allocates them to RACH message 3 when a preamble is

detected. Otherwise, the resources remain available and are considered as free by the dynamic scheduler.

The starting PRB index for the transmission of RACH Message 3 is configured by parameter:

rACHMessage3StartingPRBIndex.

The number of PRBs used for the transmission of RACH Message 3 is configured by parameter

rACHMessage3NumberOfPRBs.

The index of the MCS used for the transmission of RACH Message 3 is configured by parameter

rACHMessage3MCSIndex.







2.4.2 maxHARQmsg3Tx Parameter

Parameter maxHARQmsg3TxObject ENBEquipment/Enb/LteCell/CellRachConf/CellRachConfFDD

Range & Unit Integer [1..8]


Value 3







2.5 Contention Resolution: Message 4

Message 4 (Contention Resolution on DL-SCH): This message contains a UE Contention Resolution identity.

It is addressed on PDCCH either to the C-RNTI or to the Temporary C-RNTI.It uses HARQ. Parameter maximumNumberOfDLTransmisionsRACHMessage4

configures the maximum number of attempts for this message.


Nack

Msg4 1st Tx

Nack

Nack

ACK

Msg4 2nd Tx

Msg4 3rd Tx

Msg4 1st Tx

Msg3 Tx

If the mac-contention resolution timer expires, the contention resolution Is considered not successful. maximumNumber

OfDLTransmisionsRACHMessage4

If message 4 is successfully received and the UE contention resolution identity contained in the message

matches the content of message 3 (RRC connection request or RRC Connection Re-establishment Request)

for UEs that do not already have a C-RNTI), the Contention Resolution is considered successful and:

- The mac-contention resolution timer is stopped.

- The UEs that already have a C-RNTI resume using it.

- The UEs that do not already have a C-RNTI promote their Temporary C-RNTI to a C-RNTI.

If the mac-contention resolution timer expires, the contention resolution is considered not successful.

Parameter macContentionResolutionTimer configures the mac-contention resolution timer.






2.5 Contention Resolution: Message 4

2.5.1 Message 4 Related Parameters

Parameter maximumNumberOfDLTransmisionsRACHMessage4

macContentionResolutionTimer



Range & Unit

Integer [1..8] Enumerate{ sf8(0), sf16(1), sf24(2), sf32(3), sf40(4), sf48(5), sf56(6),sf64(7)}

Class/Cat B--Cell / Fixed C--Immediate-propagation / Fixed

Value 8 sf64







2.6 Random Access Failure

If the Random Access Response or the Contention Resolution fails, the UE backs off for a certain period of time selected randomly in the range [0, rABackoff], then restarts the procedure.

After a certain number of attempts (preambleTransMax) the MAC layer declares the Random Access procedure as failed, and notifies higher layers of the failure.

Parameter rABackoff


Range & Unit Integer [0..12]

Class/Cat B--Modem+Cell(s) / Fixed

Value 0 1 2 3 4 5 6 7 8 9 10 11 12

BackoffParameter (ms) 0 10 20 30 40 60 80 120 160 240 320 480 960

Parameter preambleTransMax


Range & Unit Enumerate { n3(0), n4(1), n5(2), n6(3), n7(4), n8(5), n10(6), n20(7), n50(8), n100(9), n200(10) }

Class/Cat C--Immediate-propagation / Fixed

Value n3(0)







2.7 RACH Power Control

Open-loop power control is applied for initial transmission of RACH.The transmit power is determined taking into account the total uplink interference

level and the required SINR operating point.Transmit power can be determined at the UE as:

PRACH_msg1 = min {PMax, PL + P0_PREAMBLE + ∆PREAMBLE + ( N PREAMBLE– 1) x P ∆RAMP_UP)

Parameter preambleInitialReceivedTargetPower preambleTransmitPowerStepSize


Range & Unit

Enumerate{ dBm-120(0), dBm-118(1), dBm-116(2), dBm-114(3), dBm-112(4), dBm-110(5), dBm-108(6), dBm-106(7), dBm-104(8),dBm- 102(8), dBm- 100(10), dBm-98(11), dBm 96(12),dBm-94(13), dBm-92(14), dBm-90(15) }

Enumerate{dB0(0), dB2(1), dB4(3), dB6(4)}

Class/Cat C--Immediate-propagation / Optimization - Tuning

Value -104 6

• The term PL is the downlink path loss estimated at the UE from DL RS.

• P0 _ PREAMBLE is the starting preamble transmit power offset configured by parameter

preambleInitialReceivedTargetPower.

• ΔPREAMBLE is the power offset value dependent on PRACH preamble format. It is harrcoded to 0 dB in LA3.0.

• ΔPRAMP_UP is the power ramping step size. It is configured by parameter preambleTransmitPowerStepSize.

• NPREAMBLE is the maximum number of preamble transmissions.

Engineering Recommendation: Parameter preambleInitialReceivedTargetPower This parameter is a key RF

optimization parameter that impacts connection setup performance and UL interference to neighboring

cells. Higher values will minimize the repetitions/ RACH attempts and hence expedite connection setup,

but will cause higher interference to other cells. Lower values will tend to increase RACH repetition/

connection setup delay. Ideally initial power should be set high enough to achieve good success at 1st

attempt at reasonable IoT loading levels.






3 RRC Connection Management








It is supposed that during the cell setup phase the PRACH is configured and setup in the cell.The PRACH configuration is indicated to the UE in System Information SIB2

RACH

UplinkTransport channels

UplinkPhysical Channels

PRACH PUCCH

Random Access PreambleRACH: 5 bits RA-RNTI

Random Access ResponseDL-SCH: RA-RNTI, TA, initial UL grant,Temp C-RNTI

No HARQ, semi-sync with message 1, RA-RNTI

RRC Connection Establishement

The UE transmits a Random Access Preamble. When the eNB correctly receives a Random Access Preamble

and if eNB resources are available it will respond with Random Access Response:

In the Random Access Preamble the eNB MAC will transmit:

- the RA-RNTI corresponding to the received Random Access Preamble, RA-RNTI = 1+ sub-frame number.

- the Timing Advance (received from L1),

- an initial UL grant to be used by the UE for the next UL RRC message (i.e. RRC CONNECTION REQUEST)

A temp C-RNTI (The IE C-RNTI identifies a UE having a RRC connection within a cell).

The temp C-RNTI allocation is done at MAC layer. The association of tempcCRNTI and granted UL

resources is stored at MAC layer.







3.2 RRC Connection Establishement

RRC connection establishment involves SRB1 establishment. It is used to transfer the initial NAS dedicated information/ message from the UE to

EUTRAN.

Signaling Radio Bearers (SRB) are defined as Radio bearers that are used only to transmit RRC and NAS messages.

SRB’s are classified into:

Signaling Radio Bearer 0: SRB0: RRC message using CCCH logical channel.Signaling Radio Bearer 1: SRB1: is for transmitting NAS messages over DCCH logical channel.Signaling Radio Bearer 2: SRB2: is for high priority RRC messages. Transmitted over DCCH logical channel.

Note: the SRB0 is established at cell setup. SRB1 is secure; that is, it is integrity protected and, if a

ciphering algorithm is available, then it is also ciphered by the PDCP layer.

NAS messages, using DCCH logical channel.

SRB2 is secure; that is, it is integrity protected and, if a ciphering algorithm is available, then it is also

ciphered by the PDCP layer







3.2 RRC Connection Establishement [cont.]

RRC Connection RequestUE Identity, Establishment cause

RRC Connection SetupRadioResourceConfigDedicated

RRC Connection Setup CompleteSelected PLMN-Identity,RegisteredMMENAS-DedicatedInformation

UERRC-Idle

UERRC-

Connected

CCCH/SRB0

CCCH/SRB0

DCCH/SRB1

It is assumed that a CCCH is available in the cell in order to receive the RRC CONECTION REQUEST message on UL-CCCH.After the UE initiates Random Access procedure (contention-based) by sending a Random Access Preamble, the eNB will respond with a Random Access Response allocation a Temp C-RNTI.If ADMISSION CONTROL is passed, a new UE context is created and SRB1 is setup in the eNB. The initial UE identity and the allocated C-RNTI are stored in the UE context.The RRCConnectionSetup is transmitted to the UE using CCCH. The message will contain SRB1 configuration.

Defense mechanisms: An internal guard timer is started on transmission of RRC CONNECTION SETUP message.The procedure ends on eNB when it receives the RRC CONNECTION SETUP COMPLETE message and the guard timer is stopped.On reception of the RRCConnectionSetupComplete message, the eNB will use the IEs NAS-DedicatedInformation , SelectedPLMN-Identity, RegisteredMME (if present) to initiate the S1 dedicated establishment procedure.UE is in RRC connected state. SRB1 is established.







3.3 RRC Connection Establishement Failures

RRC Connection RequestUE Identity, Establishment cause

RRC Connection Reject T302(information element waitTime)

eNBInternalFailure

T302

RRC Connection Setup

T300

SIB2 ( T300)

RRCConnectionRequest message with RRCConnectionReject including the IE waitTime set to the MIM

parameter t302 in MO UeTimers.

The ENB may fail to set up the RRC Connection for the following reasons:

- ADMISSION CONTROL failure

- The cell is barred (indicated by MIM parameter LteCell/cellBarred)

- All S1 links are down (indicated by the fact that all MmeAccess managed objects are in state different from Enabled/None)

- Internal reasons.

- No UE context is created.

• t302: This UE timer is started upon reception of RRCConnectionReject and is stopped upon successful RRC

establishment or cell re-selection.

Sent in RRCConnectionReject (information element waitTime)

• t300: This UE timer is started when sending RRCConnectionRequest and is stopped upon reception of

RRCConnectionSetup or RRCConnectionReject. Broadcast in SystemInformationBlockType2







3.3 RRC Connection Establishement Failures [cont.]

RRC Connection Complete

RRC Connection SetupNAS UE-ID

SRB Radio Resources Configuration

defense timerCCCH/SRB0

DCCH/SRB1

When the eNB transmits the RRC CONNECTION SETUP message to the UE a defense timer is started in order

to prevent the scenario when the UE does not receive the message due to e.g; cell reselection. If the eNB

does not receive RRC CONNECTION SETUP COMPLETE before the timer expiry, the RRC connection is

considered as failed and the eNB will delete UE context and release any associated

eNB resources.






3.3 RRC Connection Establishement Failures

3.3.1 Timers Parameters

Parameter t302 t300 rrcProcedureDefenceTimer

Object ENBEquipment/Enb/DedicatedConf/UeTimers ENBEquipment/Enb

Range & Unit

Integer in s[1..16] step=1

Enum in s[ms100, ms200, ms400, ms600, ms1000, ms1500, ms2000]

Integer in ms[50..3000] Step = 10

Class/Cat C--New-set-ups / Fixed C / Optimization - Tuning

Value5 ms100 1000

rrcProcedureDefenceTimer: This eNB internal defence timer is used to monitor the non answer from the

UE in case of any RRC procedure. The timer is started in the eNB at message transmission and stopped at

response message reception from the UE. At timer expiry the procedure is failed.






4 UE EUTRAN Attach






Security mode Command

RRC Connection Establishment

4 UE EUTRAN Attach

4.1 UE EUTRAN Attach

Measurement Configuration Phase N°01

S1-AP Initial UE Message Request

NAS Service Request

S1-AP Initial context setup request

RRC Connection ReconfigurationFor Default Bearer Establishment

RRC Connection Reconfuguration

RRC Connection Reconfiguration Complete

S1-AP Initial context setup response

MME

RRC Connection Setup complete

Measurement Configuration Phase N°02

S1AP E-RAB Setup RequestRRC Connection ReconfigurationFor Subsequent

Radio Bearer Establishment

S1-AP E-RAB Setup Response






4 UE EUTRAN Attach

4.2 S1-Setup

S1 SCTP Association is set up

MME

S1 SETUP REQUESTGlobal eNB IDeNB NameSupported TAs (1 to 256)>TAC>Broadcast PLMNs (1 to 6)>>PLMN Identity

S1 SETUP RESPONSEMME Name

Served PLMNs (1 to 32)>PLMN Identity

Served GUMMEIs (1 to 256)>GUMMEI

Relative MME CapacityCriticality Diagnostics

The eNB initiates the procedure by sending a S1 SETUP REQUEST message including its own configuration

data to the MME. This message shall be the first S1AP message sent after the TNL association has become

operational, i.e. the S1 SCTP association is successfully setup

The MME responds with S1 SETUP RESPONSE including its own configuration data.

The received data shall be stored in the eNodeB and used for the duration of the TNL association. It may be

updated by a subsequent MME Configuration Update procedure. It shall not be erased during a Reset

procedure. When this procedure is finished, S1 interface is operational and other S1 messages can be

exchanged; in particular, calls can be set up.

To avoid memory consumption, the ENB will limit the number of saved information to 16 Served GroupIDs

and 16 Served MMECs. In LTE networks, one MME should support only one GroupID and one MME code. The

potential issue is with configuration data received for other RATs (2G or 3G) which may exceed our design

values. If more than 16 instances of Served GroupIDs and Served MMECs are received, they will be ignored

by ENB, only the first ones will be stored by ENB.

In case there is at least one X2 instance setup already, on reception of a S1 Setup Response message from a

MME, an ENB shall compute the GU Group ID List






4 UE EUTRAN Attach

4.3 S1-Setup Failure


MME

S1 SETUP REQUEST

S1 SETUP FailureCause (M)

TimeToWait (O)CriticalityDiagnostics(O)

MME rejects the setupprocedure by sendingS1 SETUP FAILURE

if TimeTo Wait (O) is not received:- set timer T with a duration randomly Chosen.

if TimeToWait (O) is received:- set timer T with a TTW (O) duration

S1 SETUP REQUEST

Set s1 Setup Timer

Set s1 Setup Timer

Set s1 Setup Timer

Stop s1Setup Timer

Timer T expires

ENB resends S1 SETUP REQUEST to the MME at most two times (for atotal of three attempts), considers the setup failed after three

consecutive failures and raises an alarm to XMS

S1 SetupFailure






4 UE EUTRAN Attach

4.3 S1-Setup Failure [cont.]


MME

S1 SETUP REQUEST

S1 SETUP REQUEST

Set s1 Setup Timer

Set s1 Setup Timer

s1Setup Timer expires

ENB resends S1 SETUP REQUEST to the MME at most two times (for atotal of three attempts), considers the setup failed after three

consecutive failures and raises an alarm to XMS

No Response To S1 Setup






4.3 S1-Setup Failure

4.3.1 s1APProcedureDefenceTimer Parameter

s1APProcedureDefenceTimer: This eNB internal defense timer is used to monitor the non answer from the MME in case of any S1-AP procedure.

The timer is started in the eNB at message transmission and stopped at response message reception from the MME. At timer expiry the procedure is failed.

Parameter s1APProcedureDefenceTimerObject ENBEquipment/Enb

Range & Unit Integer in ms[50..3000] Step = 10

Class/Cat C--New-set-ups / Optimization - Tuning

ValueCurrently the default value is 3000; but be careful because this one is subject to modification.






4 UE EUTRAN Attach

4.4 Bearer Management

Each EPS bearer is either a GBR or a non-GBR bearerA GBR bearer is associated with a GBR and a MBRGBR is the guaranteed bit rate provided by the bearer serviceMBR limits the bit rate that can be expected to be provided by a GBR bearerA non-GBR bearer is not associated with a GBR (but may be associated with a MBR)

ePC

RRC Connection

ePS Default Bearer

ePS Dedicated Bearer

Guaranteed Bit Rate (GBR)Service will not experience congestion-related packet loss (provided that the user traffic is compliant to

the agreed GBR QoS parameters)

Established on demand because it blocks transmission resources by reserving them in the admission control

Function Precedence of service blocking over service dropping in congestion situation

Non-Guaranteed Bit Rate (NGBR)

Service must be prepared to experience congestion-related packet loss

Can remain established for long periods of time because it does not block transmission resources

Precedence of service dropping over service blocking in congestion situation






4 UE EUTRAN Attach

4.4 Bearer Management [cont.]

Label ARP

Bearer Type

DelayBudget

Loss Tolerance

GBR Non GBR

GBR AMBR

MBR

SAE Bearer QoS

Each bearer is assigned one and only one QoS Class Identifier (QCI).

QCI is used within the access network as a reference to node-specific parameters that control packet-forwarding treatment (e.g. scheduling weights, admission thresholds, queue management thresholds, link layer protocol configuration such as ARQ and HARQ parameters, etc.)

The standardized QCI label characteristics describe the packet forwarding treatment through the network based on the following parameters:

Resource Type (GBR or non-GBR)

Priority

Packet Delay Budget (PDB)

Packet Error Loss Rate (PLR)



Section 1 · Module 3 · Page 57Section 1 · Module 3 · Page 57Section 1 · Module 3 · Page 57



4 UE EUTRAN Attach

4.4 QoS Parameters

9 QoS classes are standardized for LTE. A given QoS Class ensures that applications/services mapped to that QoS Class

receive the minimum level of QoS.

QCI Bearer Type Priority Packet delay budget Packet Loss Rate

1 GBR 2 100 ms 10-2

2 GBR 3 150 ms 10-3

3 GBR 4 50 ms 10-3

4 GBR 5 300 ms 10-6

5 NGBR 1 100 ms 10-6

6 NGBR 6 300 ms 10-6

7 NGBR 7 100 ms 10-3

8 NGBR 8 300 ms 10-6

9 NGBR 9 300 ms 10-6

An SAE bearer is a logical aggregate of one or more Service Data Flows (SDFs) running between a UE and a

PDN Gateway. These SDFs share the same QoS treatment and performance characteristics for that bearer.

SDFs with different QoS requirements need the establishment of another bearer.

The service level (i.e., per SDF or per SDF aggregate) QoS parameters are QCI, ARP, GBR, and MBR.



Section 1 · Module 3 · Page 58Section 1 · Module 3 · Page 58Section 1 · Module 3 · Page 58



4.4 QoS Parameters

4.4.1 ALU QoS Templates

Parameter qCI trafficRadioBearerConfName packetDelayBudget logicalChannelPrio

rityDL

ObjectENBEquipment/Enb/DedicatedConf/TrafficRadioBearerConf

Range & Unit

Integer [1…255]

String of up to 64 characters

Integer [30..10000] step = 10 ms

Integer[1..255]


C—Immediate-propagation / Fixed B--Cells-of-eNB / Fixed

Value1 QCI1-GBR 2 80

2 QCI1-GBR 4 130

3 QCI1-GBR 3 30

4 QCI1-GBR 5 280

5 QCI1-nGBR 1 80

6 QCI1-nGBR 6 280

7 QCI1-nGBR 7 80

8 QCI1-nGBR 8 280

9 QCI1-nGBR 9 280

An instance of object TrafficRadioBearerConf needs to be generated for each QCI. Up to 255 instances can

be generated, 9 of which are

mandatory and correspond to the standardized QCIs (i.e. QCIs 1-9). Up to 246 additional instances can be

generated by the operator to define customized QCIs

(adapted to their own services if none of the standardized QCIs meets the PDB requirement(s) of the

service(s) in question).

In ALU templates, only 9 instances corresponding to the standardized QCIs are generated and listed in the

Table shown on the slide.

The Packet Delay Budget (PDB) is defined in 3GPP (see Table 1 for standardized QCI PDBs) as an end-to-end

delay, i.e. it corresponds to the delay between the UE and the Packet Data Network – Gateway (PDN-GW).

The values provided in the table above were derived by subtracting 20 ms to the end-to-end delay so as to

obtain the radio interface packet delay budget (i.e. delay between eNB and UE).

This delay is the average between the case when the PDN-GW is located "close" to the eNB (roughly 10 ms)

and the case when the PDN-GW is located "far" from the eNB, e.g. in case of roaming with home routed

traffic (the one-way packet delay between Europe and the US west coast is roughly 50 ms). Note that the

20 ms average is weighted average, meaning that it takes into account the fact that roaming is not a typical

scenario.

Subtracting this 20ms average delay to the end-to-end PDB will lead to the desired performance in most

cases.






4 UE EUTRAN Attach

4.5 eRAB Establishement

CACBased on ARP

• List Of Successful RAB(s) Established

• List Of RAB(s) Failed to be setup

• S1 : Initial ContextSetup Failure

• S1 : Initial Context Setup Response

S1 : Initial Context Setup FailureS1 : Initial Context Setup Response

CACBased on ARP

CACBased on ARP

Support of partial failures during Initial Context Setup and E-RAB setup is always enabled beginning with

Release LA3.0.

The eNB continues to setup the remaining radio bearers in case one of radio bearers fails to be setup.






5 Admission Control






5 Admission Control

5.1 Radio Admission Control

Radio Call Admission Control (Radio CAC) is a key functionality of the RRC layer, it:Provides the means to decide whether to accept or reject the request for the addition of a new UE context or new bearer. Manages the deletion of bearers or UE contexts.Maintains RDL/ RUL (Current estimated cell resource consumption in DL/UL).

Parameters dlSigConsumption and ulSigConsumption configure the projected DL/ULconsumptions (in PRBs/s) of the SRB1 & SRB2 respectively of the UE.

Parameter dlOverheadConsumption

ulOverheadConsumption

dlSigConsumption ulSigConsumption

Object ENBEquipment/Enb/LteCell/RadioCacCellRange & Unit

Integer [0..100000] PRBs/second


Value 2200 5600 2 1

The estimated cell resource consumptions (RDL and RUL) are updated afterwards as bearers are created or

deleted:

• When a radio bearer is created, the estimated cell consumption is increased by the amount corresponding to the bearer’s projected consumption, in PRBs/s.

• When a bearer is deleted, the estimated cell consumption is decreased by the same amount.

When a UE context (i.e. UE SRB1 berarer) is created:

• The Radio CAC function updates the cell resource consumption metrics RDL and RUL as follows:

RDL = RDL + dlSigConsumption and RUL = RUL + ulSigConsumption

• The Radio CAC function updates the UE’s individual resource consumption as follows:

R(UE)DL = dlSigConsumption and R(UE)UL = ulSigConsumption

When a UE context is deleted:

• The Radio CAC function updates the cell resource consumption metrics RDL and RUL as follows:

RDL = RDL - R(UE)DL and RUL = RUL - R(UE)UL

i.e. the individual resource consumption of the UE is removed from the total cell resource consumption.

• The Radio CAC function decrements the number of active users Nusers.

In the case when there are no more active UEs in the cell (Nusers = 0) after the deletion, RDL and RUL are

reset equal to parameters dlOverheadConsumption and ulOverheadConsumption, respectively.






5 Admission Control

5.1 Radio Admission Control [cont.]

Parameters dlVOIPConsumption and ulVOIPConsumption configure the projected downlink and uplink consumptions (in PRBs/s) of a VoIP radio bearer .

Parameters dlPRBconsumptionPerKbps and ulPRBconsumptionPerKbps configure the projected downlink and uplink consumptions (in PRBs/s per Kbps of GBR) of a non VoIP GBR radio bearer (i.e. GBR-2 or GBR-3 or GBR-4 radio bearer).

Parameter dlVOIPonsumption

ulVOIPConsumption

dlPRBconsumptionPerKbps

ulPRBconsumptionPerKbps

Object ENBEquipment/Enb/LteCell/RadioCacCell

Range & Unit

Integer [0..100000] PRBs/second

0..100] step = 0.1 PRBs/second per kbps of GBR

Class/Cat C--New-set-ups / Fixed C--New-set-ups / Fixed

Value 0 600 0,8 5,7

When a VoIP radio bearer is created:

• The Radio CAC function updates the cell resource consumption metrics RDL and RUL as follows:RDL = RDL + dlVOIPConsumption and RUL = RUL + ulVOIPConsumption

• The Radio CAC function updates the UE’s individual resource consumption as follows:R(UE)DL = R(UE)DL + dlVOIPConsumption and R(UE)UL = R(UE)UL + ulVOIPConsumption

When a (non-VoIP) GBR radio bearer with a GBR of BRUL kbps in the UL and a GBR of BRDL kbps in the DL is

created:

• The Radio CAC function updates the cell resource consumption metrics RDL and RUL as follows:RDL = RDL + dlPRBconsumptionPerKbps × BRDL and RUL = RUL + ulPRBconsumptionPerKbps × BRUL

The Radio CAC function updates the UE’s individual resource consumption as follows:R(UE)DL = R(UE)DL + dlPRBconsumptionPerKbps × BRDL and R(UE)UL = R(UE)UL + ulPRBconsumptionPerKbps × BRUL

When a VoIP radio bearer is deleted:

• The Radio CAC function updates the cell resource consumption metrics RDL and RUL as follows:RDL = RDL – dlVOIPConsumption and RUL = RUL - ulVOIPConsumption

• The Radio CAC function updates the UE’s individual resource consumption as follows:R(UE)DL = R(UE)DL – dlVOIPConsumption and R(UE)UL = R(UE)UL – ulVOIPConsumption

When a (non-VoIP) GBR radio bearer with a GBR of BRUL kbps in the UL and a GBR of BRDL kbps in the DL is

deleted:

• The Radio CAC function updates the cell resource consumption metrics RDL and RUL as follows:RDL = RDL - dlPRBconsumptionPerKbps × BRDL and RUL = RUL - ulPRBconsumptionPerKbps × BRUL

• The Radio CAC function updates the UE’s individual resource consumption as follows:R(UE)DL = R(UE)DL - dlPRBconsumptionPerKbps × BRDL and R(UE)UL = R(UE)UL - ulPRBconsumptionPerKbps × BRUL






5 Admission Control

5.2 Admission Decision

The acceptance of a UE context creation is conditioned by the availability of enough(time/frequency) resources to accommodate the corresponding dedicated SignalingRadio Bearers (SRB1 and SRB2) or data radio bearer.

When a UE context creation request is received:

If((RDL + dlSigConsumption)/ dlTotalDLresourceCount ) × 100 ≥ dlAdmissionThresholdor((RUL + ulSigConsumption)/ ulTotalULresourceCount ) × 100 ≥ ulAdmissionThresholdthen the Radio CAC function rejects the request.

The total uplink resource count and the total downlink resource count are defined by parameters

dlTotalDLresourceCount and dlTotalDLresourceCount, respectively.

Parameters dlAdmissionThreshold and dlAdmissionThreshold configure the percentage of the total

resource count to consider for the acceptance of a UE context creation request or a radio bearer creation

in the downlink and the uplink, respectively.






5 Admission Control

5.2 Admission Decision [cont.]

When a VoIP radio bearer creation request is received:

if((RDL + dlVOIPConsumption) / dlTotalDLresourceCount × 100) ≥ dlAdmissionThresholdor((RUL + ulVOIPConsumption) / ulTotalULresourceCount × 100) ulAdmissionThresholdthen the Radio CAC function rejects the request.

When a request for the creation of a (non-VoIP) GBR radio bearer with a GBR of BRUL kbps in the UL and a GBR of BRDL kbps in the DL is received,

if((RDL + (dlPRBconsumptionPerKbps × BRDL))/ dlTotalDLresourceCount ×100)

≥ dlAdmissionThresholdor((RUL + (ulPRBconsumptionPerKbps × BRUL))/ ulTotalULresourceCount ×100)

≥ ulAdmissionThresholdthen the Radio CAC rejects the request.






5 Admission Control


If at least one of the following (configurable) limits has already been reached when a request for the creation of a UE context is received, the request is rejected:

The maximum number of connected users on the cell (including emergency and non emergency users), configured by parameter maxNbrOfUsers.The maximum number of connected users per eNodeB, configured by parameter maxNumberOfCallPerEnodeB.

Parameter maxNumberOfCallPerEnodeB maxNbrOfUsers nbOfContextsReserved

ForEmergencyCallsObject ENBEquipment/Enb/LteCell/RadioCacCell

Range & Unit Integer [0..200] Integer [0..20]


Value180 (LA3.0.1)

20(LA3.0.1)

0

Also, if the UE context creation is for a non-emergency call and the number of connected non-emergency

users has already reached (maxNbrOfUsers - nbOfContextsReservedForEmergencyCalls), then the

request is rejected.

In other words, the number of non-emergency users is limited to (maxNbrOfUsers

nbOfContextsReservedForEmergencyCalls).

This is to reserve nbOfContextsReservedForEmergencyCall for emergency call setup.

Engineering Recommendation: Parameter nbOfContextsReservedForEmergencyCalls

This parameter imposes an additional limit on the number of non emergency users that can be connected

simultaneously in the cell. High settings will reserve many contexts for emergency users but will leave

fewer contexts for non emergency calls. If set to a too high value, contexts will be wasted given that the

average number of emergency calls is generally low.






5 Admission Control


If at least one of the following (configurable) limits has already been reached when a request for the creation of a data bearer is received, the request is rejected:

The maximum number of data bearers per UE: maxNbOfDataBearersPerUe.The maximum number of data bearers per eNodeB: maxNbOfDataBearersPerEnodeB.The maximum number of data bearers setup on the current cell: maxNbOfDataBearersPerCell.The maximum number of data bearers per the QCI in question: maxNbrOfBearersPerQci.

Parameter maxNbOfDataBearersPerUe

maxNbOfDataBearersPerEnodeB

maxNbOfDataBearersPerCell maxNbrOfBearersPerQci

Object ENBEquipment/Enb/LteCell/RadioCacCell

Range & Unit Integer [1…8] Integer [1…600] Integer [0..756] Integer [0..756]


A--full-eNB-reset / Fixed

C--New-set-ups / Fixed C--New-set-ups / Fixed

Value4

240(3 Cells)

80

QCI1

QCI2

QCI3

QCI4

QCI5

QCI6

QCI7

QCI8

20 60 60 60 80 80 80 80






6 Paging






6 Paging

6.1 Paging Channels

Paging messages are sent over the PCCH logical channel. PCCH is mapped onto the PCH transport channel, which itself is carried on the PDSCH

physical channel.Transport format and resource allocation for the PCH channel is signalled on the

PDCCH channel, using the dedicated P-RNTI (defined as 0xFFFE)

BCH DL-SCH MCH

Downlink

Transport channels

Downlink

Physical ChannelsPDSCHPBCH PHICH P M CH

PCH

Note: PCH and DL-SCH are both carried at L1 on PDSCH. The L1 channel PDCCH informs the UE about DLf-SCH and PCH allocation.






6.1 Paging Channels

6.1.1 Paging Occasion Determination

The moment at which a given UE can be paged in a paging frame is called a Paging Occasion. The paging occasion for a given UE is calculated using the 3 following parameters:

UE_ID: equal to the UE IMSI modulo 1024DRX Paging Cycle: either the default value transmitted in the System

Informationparameter nB, transmitted in the System Information (in SIB2), which defines a sort of "paging occasion density" within a radio frame.

These three parameters participate in creating time diversity for the sending of paging messages.

The On duration timer is equal to 10ms in LA3.0.

The (long) DRX cycle length values supported in LA3.0 for ANR are 160 ms and 320 ms.

UE ID equal to IMSI modulo 1024 (but appeared like s-TMSI in the paging traces) .

This is provided to the eNodeB in the S1 Paging message by mandatory information element "UE Identity

Index Value", DRX Paging Cycle: either the default value transmitted in the System Information

(defaultPagingCycle in SIB2 / and Enb::defaultPagingCycle in the MIM), or the UE-specific value received in

the S1 Paging message if it is shorter.






6.1 Paging Channels

6.1.1 Paging Occasion Determination [cont.]

The UE_ID splits the UE population into groups with identical paging occasions.

All UEs with the same UE_ID shall be paged within the same unique paging occasion.

The DRX Paging Cycle defines the period over which paging messages will be spread.

A given UE will have one and only one paging occasion during the paging cycle.Parameter nB is expressed as a multiple or divisor of the paging cycle: it defines the ratio

of paging occasions to the number of radio frames.

1023

1022

3

0

2

1

n

n -1

1

0

mod 1024IMSI

(Up to 1021

Values)

Paging Occasion1 to 1024

UE_ID

A given paging occasion is always shared by at least four UE_ID groups, and generally much more

(in the "worst" case, all UEs share a single paging occasion).

if the occasion was missed (because the S1 Paging came after the occasion or because there were too many

paging messages buffered for the given paging occasion), the eNodeB will have to buffer the paging until

the next paging cycle length of the paging cycle is a trade-off between mobile terminating call

establishment performance on one hand (the shorter the cycle the sooner the mobile will be paged)

and paging capacity on the other hand (the longer the cycle, the more paging occasions there will be). The

DRX Paging Cycle may be set to 32, 64, 128, or 256 radio frames






6.1.1 Paging Occasion Determination

6.1.1.1 Paging Related Parameters

Parameter defaultPagingCycle nB

Object ENBEquipment/Enb ENBEquipment/Enb/LteCell

Range & Unit Enumerate[rf32, rf64, rf128, rf256]

Enumerate[fourT, twoT, oneT, halfT, quarterT, oneEightT, onSixteenthT, oneThirtySecondT]

Class/Cat C--Immediate-propagation / Fixed C--Immediate-propagation / Fixed

Value rf32 oneTEngineeringRecommendation

To allow fixed VoIP and PCCH bandwidth allocation, up to 1 paging sub-frame per frame is supported: nB <= T. As a result, the values fourTand twoT should not be used.






6.1.1 Paging Occasion

6.1.1.2 Discontinuous Reception (DRX) Forced Mode

Downlink scheduler does not schedule the UE anymore for initial HARQ transmissions

DRX Forced Mode

DL Scheduler

DRX MAC Command

DRX Configured

UL Scheduler

12 UE stops transmitting

the SRS 3

Uplink scheduler detects the lack of SRS as a loss of uplink sychnronizationand stops scheduling the UE until starts transmitting the SRS again (once it gets out of DRX mode).

4

Meas Report, UL RRCMesg (e.g. HO) 5SRB 1

The UE comes out of DRX mode if it sends a measurement report or some other UL RRC message (e.g. for handover) on SRB1.

5

The UE comes out of DRX mode if it sends a measurement report or some other UL RRC message (e.g. for

handover) on SRB1.

If the UE does not get out of the DRX mode at the end of the DRX cycle, the Downlink scheduler sends a

Timing Advance MAC command (during the DRX ON duration of the next DRX cycle) in order to force the UE

out of the DRX mode.

Note that the measurement during the DRX mode is of best effort type, meaning that some UEs may get out

of DRX mode without performing any measurement. Also, some UEs may get out of DRX mode by themselves

and thus do not need a Timing Advance command.











End of ModuleSession Management





Module 4Mobility Management

Issue

Section 1





· 9400 LTE LA3.0 Radio Algorithms and Parameters description· Mobility Management1 · 4 · 2

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Document History





Module Objectives


Describe the mobility procedures within eUTRAN network for UE in RRC Idle Mode and UE in RRC Connected mode.List the different mobility features supported in LA3.0 and the parameters related to the activation and optimization of each.Describe the inter RAT mobility algorithms, triggers and parameters











Table of Contents


1 Intra-LTE Mobility 71.1 Intra Frequency RRC Idle Mode Mobility 8

1.1.1 Cell Reselection Algorithm Description 91.1.1.1 Pcompensation 111.1.1.2 Sintrasearch Parameter 121.1.1.3 Cell Reselection Priority 13

1.1.2 Cell Reselection Criteria 141.1.2.1 SIB 4 Broadcasting And Blacklisted Cells 17

1.2 Intra Frequency RRC Connected Mode Mobility 201.2.1 Intra eNB Mobility 21

1.2.1.1 Failure Cases 231.2.2 Inter eNB-X2 Mobility 24

1.2.2.1 Inter eNB-X2 Mobility: Handover Preparation 25Handover Preparation Parameters 26

1.2.2.2 Inter eNB-X2 Mobility: Execution and Completion 271.2.2.3 Failure Cases 28

1.2.3 Inter eNB-S1 Mobility 291.2.3.1 Inter eNB-S1 Mobility: Preparation 301.2.3.2 Inter eNB-S1 Mobility: Execution & Completion 311.2.3.3 Failure Cases 321.2.3.4 eNB-S1 Mobility Parameters 33

1.3 The Last Visited Information 341.4 Intra-frequency Measurement Reporting Setting 35

1.4.1 measurementPurpose Parameter 361.4.2 RrcConnectionReconfiguration Parameters 37

1.5 Event A3 and HO Measurement 381.6 Measurement Configuration Model 39

1.6.1 sMeasure, trigger/reportQuantity Parameters 401.6.2 hystere sis and timeToTrigger Parameters 411.6.3 maxReportCells Parameter 42

1.7 Automatic Neighbor Relation (ANR) 431.7.1 ANR Phases 441.7.2 ANR Activation 451.7.3 ANR Neighbor Relation Creation Function 46

1.7.3.1 Neighbor Relation Process 47Main Parameters Included in Neighbor Relation 49

1.7.4 ANR Measurement Configuration 501.7.5 Set Up X2 Links 51

1.8 Inter-Frequency RRC Connected Mode Mobility 522 Inter-RAT Mobility: eUTRAN-UTRAN 53

2.1 RRC Idle Mode Mobility: Cell Reselection 542.1.1 Cell Reselection Algorithm Description 55

2.1.1.1 Limit the UTRA FDD Measurement 572.1.1.2 Cell Reselection Related Parameters 582.1.1.3 Cell Reselection Priorities Handling 61

2.2 RRC Connected Mode Mobility: Redirection 632.2.1 eUTRA To UTRA Redirection Procedure 64

2.2.1.1 eUTRA To UTRA Measurement Reporting Setting 662.2.1.2 UTRA Event B2 Configuration 67

RRC Measurement Configuration 68Report Configuration 69

2.2.2 Thresholds For Inter-Rat Mobility Foe Event B2 702.2.2.1 Thresholds & Measurement Parameters For B2 71

3 RRC Connected Mobility: PS Handover 723.1 PS Handover to UTRAN 73







3.1.1 PS HO Related Parameters 743.2 PS HO Procedure In eNB: Preparation Phase 753.3 PS HO Procedure In eNB: Handover Execution 763.4 PS HO Preparation Phase Related Parameters 77

4 CS FALLBACK 784.1 CSFB Function 79

4.1.1 CS Fallback Procedure in eNB 804.2 CSFB Triggered By An Idle UE 814.3 CSFB Triggered By a Connected UE 824.4 CSFB Triggered by PS Handover 834.5 CSFB UE Measurement Configuration 85

5 Evolved Multi-Carrier Traffic Allocation (e-MTCA) 865.1 e-MTCA Overview 875.2 e-MCTA Triggers & Filter 91

5.2.1 Coverage Alarm Entry Measurement Configuration 925.3 Input/Output: Unsorted RAT/Carrier List 935.4 e-MCTA Filtering Algorithm 945.5 Service Table 96

5.5.1 e-MTCA Priority 975.5.2 service Type Parameter 98

5.6 e-MTCA Process for RRC Measurement 996 Measurement Gap Configuration 100

6.1 Measurement Gaps 1016.1.1 Measurement Gaps Pattern 1036.1.2 DRX Configuration With Measurement GAP 104






1 Intra-LTE Mobility






1.1 Intra Frequency RRC Idle Mode Mobility

Cell Reselection is a procedure triggered by the UE in Idle Mode to determine which LTE cell to camp on.

When a UE, camps on a cell it monitors its broadcast and paging channels. The cell selection and reselection is controlled by the System Information parameters

provided in SIB1, SIB3 and SIB4

SIB1,S

IB 3,

SIB4

BCH






1.1.1 Cell Reselection Algorithm Description

Cell Reselection is a procedure run in the UE that relies on: - Measured RF quality related metrics of camped on and detected cells - System parameters broadcast by the cell on which the UE is currently camping on. Cell Reselection criterion is fulfilled when when : Srxlev > 0

Where: Srxlev = Qrxlevmeas – ( Qrxlevmin + Qrxlevminoffset) - Pcompensation

Srxlev Calclated by the UE Cell Selection RX level value (dB).

Qrxlevmeas Measured by the UE Measured cell RX level value (RSRP

Qrxlevmin qRxLevMin or qRxLevMinIntraFreqNeighbor

Minimum required RX level in the cell (dBm).

Qrxlevminoffset qRxlevminoffset Offset to the signalled Qrxlevmin

Pcompensation Calculated by the UE(See below) max(Pemax – Pumax, 0) (dB).

Pemax CellSelectionReselectionConf::pMax Maximum TX power level an UE may use when transmitting on the uplink in the cell (dBm)

Pumax Hardcoded Maximum RF output power of the UE (dBm) according to the UE power class as defined.

The signalled value QrxlevminOffset is only applied when a cell is evaluated for cell selection as a result of a

periodic search for a higher priority PLMN while camped normally in a VPLMN. During this periodic search for

higher priority PLMN the UE may check the S criteria of a cell using parameter values stored from a different

cell of this higher priority PLMN.






1.1.1 Cell Reselection Algorithm Description [cont.]

Parameter pMax qRxLevMin qRxlevminoffset Object ENBEquipment/ Enb/ LteCell/ CellSelectionReselectionConf

Range & Unit Integer,dBm [-30..+33] step = 1

dBm [-140..-44] step = 2

dB [2..16] step = 2


Value 0 -120 2 (default:2)


Currently, we recommend set a pMax value in order to get Pcompensation to 0: The value 23 dBm is the recommended value.

The field tests trial have shown best results with the value : -120 dBm This parameter has impact on idle mode coverage

• qRxLevMin : This parameter configures the min required RSRP level used by the UE in cell reselection on the frequency Carrier for the neighbors cells.The value sent over the RRC interface is half the value configured. The UE then multiplies the received value by 2.Broadcast in SystemInformationBlockType 3 or 5. Actual value Qrxlevmin = IE value*2 [dBm]. Specifies the minimum required Rx RSRP level in the cell. (WhereIE

value specify the message value send to the UE) Changing this value will affect cell size in terms of re-selection area. Increasing this value will lead the mobile

to start cell-selection/re-selection procedure sooner and then will artificially decrease cell size in idle mode.

• qRxlevminoffset: This parameter defines an offset to be applied in cell selection criteria by the UE when it is engaged in a periodic search for a higher priority PLMN.

The value sent over the RRC interface is half the value configured Defined in TS. Broadcast by the eNB in SystemInformationBlockType1

traSearch : This parameter specifies the threshold for the serving cell reception level, below which the UE triggers intra-frequency measurements for cell reselection.The value sent over the RRC interface is half the value provisioned; the UE then multiplies the received value by 2.

The RRC parameter is broadcast in SystemInformationBlockType3. However, if this parameter is not configured, then the RRC parameter is not broadcast in the cell, in which case, UEs in idle mode in the cell will measure for intra-frequency reselection unconditionally.






1.1.1.1 Pcompensation

Pcompensation is a compensation factor to penalize the low power mobiles. Pcompensation = max(PEMAX - PUMAX, 0)

Where: PEMAX = pMaxPUMAX = maximum UE output power (dBm) according to its power class in LTE and

operating band.

Operating BandUE LTE maximum output

power (Pumax)Class3

LTE 2100 Mhz +23dBm

LTE 2600 Mhz +23dBm

LTE 700 Mhz Upper +23dBm

LTE 700 Mhz Lower +23dBm

LTE 800 Mhz +23dBm






1.1.1.2 Sintrasearch Parameter

In order to further restrict the amount of measurement carried out by the UE in RRC-Idle mode, the following rules are used by the UE:

Sintrasearch : This specifies the threshold (in dB) for intra frequency measurements. Configuration parameter is sIntrasearch

- If SServingCell > Sintrasearch UE may choose to not perform intra-frequency measurements.

- If SServingCell ≤ Sintrasearch UE shall perform intra-frequency measurements.

SservingCell = Qrxlevmeas – (Qrxlevmin + Qrxlevminoffset) - Pcompensation

Parameter sIntraSearch Object ENBEquipment/ Enb/ LteCell/ CellSelectionReselec Range & Unit dB [0..62] step = 2

Class/Cat C--Immediate-propagation / Optimization - Tuning

Value 62 dB.

UE starts intra-frequency measurements for cell re-selection when serving cell’s RSRP value <= qRxLevMin + sIntraSearch.

(SServingCell is a S Criterion in the Serving cell, i.e SServingCell = SRxLev like formula above)

Increasing sIntraSearch value will make UE to start intra-frequency neighbor search earlier.

Test results indicate sIntraSearch should be set to the highest allowed value to minimize SINR degradation in

reselection boundaries.






1.1.1.3 Cell Reselection Priority

cellReselectionPriority: This parameter specifies the relative priority for cell reselection (0 means lowest priority).

Broadcasted in SystemInformationBlockType3 for the intra-frequency neighborhood or in SystemInformationBlockType5 for inter-frequency neighborhood.

Parameter cellReselectionPriority

Object ENBEquipment/ Enb/ LteCell/ LteNeighboring/ LteNeighboringFreqConf/ CellReselectionConfLte

Range & Unit Integer [0..7] step = 1

Class/Cat C / Optimization - Tuning

GSM

UMTS

LTE

Hrpd

LTE

The value 5 for cellReselectionPriority should be good.

With this value, we can build the following priority rancking cells:

The LTE cells with the highest priority: setting CellReselectionConfLte::cellReselectionPriority to 5

The UMTS cells with a priority less high: setting CellReselectionConfUtra::cellReselectionPriority to 3 for

example

The GERAN cells with lowest priority: setting CellReselectionConfGERAN::cellReselectionPriority to 2 for

example






1.1.2 Cell Reselection Criteria

The cell-ranking criterion Rs for serving cell and Rn for neighboring cells is defined:

Rs = Qmeas,s + QHyst

Rn = Qmeas,n - Qoffset

In all cases, the UE will actually reselect the new cell, only if the following conditions are met:

1- The new cell is better ranked than the serving cell during a time interval tReselectionEUTRANs or tReselectionRATs

Qmeas,s + QHyst < Qmeas,n – QOffset

2- More than 1 second(s) has elapsed since the UE camped on the current serving cell. 3- If the UE is in high mobility state multiply TreselectionEUTRAN or tReselectionRATs by the IE "Speed dependent ScalingFactor” if sent on system information.

Qoffset: For intra-frequency: Equals to Qoffsets,n, if Qoffsets,n is valid, otherwise this equals to zero.

For inter-frequency: Equals to Qoffsets,n plus Qoffsetfrequency, if Qoffsets,n is valid, otherwise this equals to Qoffsetfrequency.

QHyst: This parameter configures the hysteresis value of the serving cell used by the UE for ranking criteria in cell reselection

1. The UE will perform ranking of all cells that fulfil the cell selection S criterion,

2. The cells are be ranked according to the R criteria,

3. If a cell is ranked as the best cell the UE will perform cell re-selection to that cell.






1.1.2 Cell Reselection Criteria [cont.]

RSRP Serving Cell

tReselectionEUTRAN

Cell1

Cell2

tUE triggers intra-frequency

measurementsTimer is aborted Cell 2 is Reselected

Serving Cell

Cell2

RSRP

t

Qoff

QHyst

sIntrasearch

Timer is started

Cell2 becomes better than the serving cell






1.1.2 Cell Reselection Criteria [cont.]

Parameter qHyst tReselectionEUTRAN qOffsetCell

Object eNBEquipment/ Enb/ LteCell/CellSelectionReSelect ionConf

ENBEquipment/ Enb/ LteCell/LteNeighboring/teNeighboringFreqConf/CellReselectionConfLte

ENBEquipment/ Enb/ LteCell/ LteNeighboring/ LteNeighboringFreqConf/LteNeighboringCellRelation

Range & Unit Range & Unit Enumerate in dB [dB0, dB1, dB2, dB3, dB4, dB5, dB6, dB8, dB10, dB12, dB14, dB16, dB18, dB20, dB22, dB24]

s [0..7] step = 1 Enumerate in dB [dB-24, dB-22, dB-20, dB-18, dB-16, dB-14, dB-12, dB-10, dB-8, dB-6, dB-5, dB-4, dB-3, dB-2, dB-1, dB0,dB1, dB2, dB3, dB4, dB5, dB6, dB8, dB10, dB12, dB14, dB16, dB18, dB20, dB22, dB2

Class/Cat C / Optimization - Tuning

Value dB2 2 dB3


Decreasing qHyst leads to do cell-reselection earlier.

This parameter avoid ping pong radio phenomena during the RA-Update & idle mobility.

qHyst : This parameter configures the hysteresis value of the serving cell used by the UE for ranking criteria in cell reselection. Broadcast in SystemInformationBlockType3

This parameter configures the hysteresis value of the serving cell used by the UE for ranking criteria in cell

reselection.

Decreasing qHyst leads to do cell-reselection earlier.

tReselectionEUTRAN : This parameter specifies the value of the cell reselection UE timer in the serving cell.

The parameter value under the LteNeighboringFreqConf MO pointed to by LteCell::lteNeighboringFreqConfId

(corresponding to the serving frequency) is broadcasted in SystemInformationBlockType3.

The parameter value for all other instances are broadcasted in SystemInformationBlockType5

qOffsetCell : This parameter defines the offset between the current LteCell and the LteNeighboringCell.

This parameter will be present and configured if the neighbor cell is included in the neighbor cell list to be

provided in the System Information.

In dB.Broadcast in SystemInformationBlockType4, and in SystemInformationBlockType5

qOffsetCell : This parameter defines the offset between the current LteCell and the LteNeighboringCell. This parameter will be present and configured if the neighbor cell is included in the neighbor cell list to be provided in the System Information. In dB. Broadcast in SystemInformationBlockType4, and in SystemInformationBlockType5.





SIB4:at least one neighbour EUTRAN carrier is configured. at least one instance of LteCell/LteNeighboring CellRelation

containing mandatory parameters for cell reselection. The SIB4 intraFreqNeighCellList includes the intra-frequency

neighboring cells: these are neither blacklisted nor with zero-valued.

LteNeighboringCellRelation ::qOffsetCell.If there is no neighboring cell meeting the above

requirement, the intraFreqNeighCellList is not included in SIB4. If more than 16 neighboring cells meet, only the 16

neighboring cells with the highest absolute qOffsetCell are selected. Otherwise all neighboring cells are included in the SIB4 intraFreqNeighCellList

1.1.2 Cell Reselection Criteria

1.1.2.1 SIB 4 Broadcasting And Blacklisted Cells

System Information SIB4 is broadcast only if at least one neighbour EUTRAN carrier MO has been configured.

SIB1,S

IB 3,

SIB4

BCH

A neighbor cell is defined: there exists at least one instance of LteCell/LteNeighboringCellRelation

containing mandatory parameters for cell reselection.

The SIB4 intraFreqNeighCellList includes the intra-frequency neighboring cells: these are neither blacklisted

nor with zero-valued LteNeighboringCellRelation::qOffsetCell in MIM.

If there is no neighboring cell meeting the above requirement, the intraFreqNeighCellList is not included in

SIB4.

If more than 16 neighboring cells meet the above requirement, only the 16 neighboring cells with the

highest absolute qOffsetCell are selected. Otherwise all neighboring cells meeting the above requirement

are included in the SIB4 intraFreqNeighCellList






1.1.3 Intra-frequency And Different Priorities [cont.]

Parameter threshServingLow threshXHigh threshXLowObject ENBEquipment/ Enb/

LteCell/CellSelectionReselectionConf

ENBEquipment/ Enb/ LteCell/ LteNeighboring/ LteNeighboringFreqConf/CellReselectionConfLte

Range & Unit Integer, dB [0..62] step = 2

Integer, dB [0..31] step = 1

Class/Cat C--/ Optimization - Tuning

Value 16 10 0


To get the option to reselect as soon as possible, with serving cell reception level below sNonIntraSearch, we can set threshServingLow at the same level than sNonIntraSearch.

threshServingLow: Threshold for serving cell reception level used in reselection evaluation towards lower

priority E-UTRAN frequency or RAT. The value sent over the RRC interface is half the value configured (the UE then multiplies the received value by 2) is Broadcast in SystemInformationBlockType3

threshXHigh: This parameter configures: the IE s-IntraSearch for intrafrquency included in IE

SystemInformationBlockType3 for intra-frequency, and, the IE threshX-High included in IE

SystemInformationBlockType5 for inter-frequency.

threshXLow: This parameter configures:The IE threshServingLow included in IE SystemInformationBlockType3

for intra-frequency, and, the IE threshX-Low included in IE SystemInformationBlockType5 for inter-frequency.






1.1.3 Intra-frequency And Different Priorities [cont.]

Sour

ce C

ell

Cand

idat

e ce

lls f

or

Low

er

And

upp

er p

rior

ity

TreselectionEUTRAN = 2s

RSRP

RSRP

RSRP

-110dBm

-120dBm

-104dBmUE

Chrologic State of the largestLTE Cell Measures Cell

SelectedCell

ReSelected

Qrxlevmin(SIB3)+sintrasearch

Intrasearch =62thresholdServinglow=16

Qrxlevmin(SIB3)+thresholdServinglow

UEQrexlevmin + Qrxlevminoffset+max[(pMax-Pumax),0]+threshXlow

-120+0+ Max[(23-23), 0] +0 = -120dBm

Qrexlevmin + Qrxlevminoffset+max[(pMax-Pumax),0]+threshXHigh

-120+0+ Max[(23-23), 0] +10 = -110dBm

Use case with UE Class 31 2

3

34

1 : Serving cell become less good and the RSRP level decrease under [Qrxlevmin(SIB3)+sIntraSearch]. Then cell detection of better cell is possible twice more frequently in average towards all cells, and we can detect and measured lower priority cells than the serving.

2 : Serving cell becomes worse and the RSRP level decrease under [Qrxlevmin(SIB3)+threshServingLow]. Cell

reselection would be possible, but not yet candidate cell, reaching [Qrxlevmin+Qrxlevminoffset

+Pcompensation+threshXLow].

3 : The situation just above is still reached and also, in the target cell, threshold

[Qrxlevmin+Qrxlevminoffset+Pcompensation+threshXLow] and none higher cell priority are known.

tReselectionEUTRAN is started.

During tReselectionEUTRAN, NO higher cell priority reaches[Qrxlevmin+Qrxlevminoffset+

Pcompensation+threshXHigh]

4 : tReselectionEUTRAN is achieved, reselection is triggered.






1.2 Intra Frequency RRC Connected Mode Mobility

The parameters below are in the scope of mobility activation and information options.

Be careful, it is mandatory to activate them, for mobility.

They’re “Fixed” category and they are C classparameters:

The mobility is enabled via Configuration parameter isIntraFreqMobilityAllowed set to True.ActivationService

The mobility with data forwarding enabled, the parameter isDataForwardingAllowed need to be set to True.

BTS Equipement

Activation Service

eNB

isDataForwardingAllowed:: True

isIntraFreqMobilityAllowed :: True

isInterFreqMobilityAllowed :: True/False






1.2.1 Intra eNB Mobility

• Pre-conditions:

The UE is RRC CONNECTED in the source cell.The default E-RAB is established .

• Initial state: UE in RRC CONNECTED in the source cell: SRB1/SIB2 + default bearer (+dedicated bearer) are established.

• Final state: UE in RRC CONNECTED in the target cell:

All bearers from the source cell are handed over to the target cell

UE context and associated resources are deleted in the source cell

MME SGW

S1

RRC Connection New RRC Connection

The eNB may trigger an intra-LTE handover only after the default bearer is established and security activated.






1.2.1 Intra eNB Mobility [cont.]

MME/SGW


DL Data

HO Decision

Measurement Report

RRC Connection Reconfiguration

Detach from oldcell and synchronize

to new cell

Random Access preamble

DL Data

Start transmitting DL in target cell

RRCConnectionReconfigurationComplete

Release UE associated resources in the source cell

RrcIntraEnbHo Timer

T304 Timer

MeasurementConfiguration MobilityControlInformation

TargetPCI, dlEARFCN, measurementBandwidth, Target cell, pmax, radioResourceConfigCommon.

T304.rach-ConfigDedicated RadioResourceConfigDedicated

Setup UE associated resources in the target cell

Switch DL to Target cell Start receiving UL

in Target cell

When the eNB receives a MeasurementReport it will decide if a handover procedure needs to be triggered.

In case of handover trigger, the eNB selects the target cell based on the UE measurement report and trigger

an intra-eNB handover procedure if the selected target cell belongs to the same eNB. If the selected target

cell belongs to a different eNB then trigger an inter-eNB handover procedure:

In case of intra-eNB handover, the eNB will:

- Perform admission control

- Setup L1/L2 resources in the target cell

- Perform U-plane actions in the source cell.

- Transmit the RRC CONNECTION RECONFIGURATION to the UE.

In LA3.0, in the meantime, up to 8 Bearers is supported per UE.

So, for handover, the up to 8 Bearer HO is also supported.

When the UE receives RRC CONNECTION RECONFIGURATION it is not aware whether an intra-eNB or inter-

eNB handover is to be executed. The UE has the same behaviour for both cases.

The UE stops receiving/transmitting from the source cell reconfigures its L1/L2 as requested in RRC

CONNECTION RECONFIGURATION.

The UE performs synchronization to the target cell and accesses it via a contention-based random access.

If the UE succeeds to access the target cell it will transmit RRC CONNECTION RECONFIGURATION COMPLETE.

When the eNB receives the RRC CONNECTION RECONFIGURATION COMPLETE, it will perform U-plane

actions in the target cell ALU and release UE resources in the source cell





1.2.1 Intra eNB Mobility

1.2.1.1 Failure Cases

MME/SGW


DL Data

HO Decision

Measurement Report


Switch DL to Target cell Start receiving UL

in Target cell

Detach from oldcell and synchronize

to new cell

Random Access preamble

DL Data

Start transmitting DL in target cell


Release UE associated resources in the source cell

RrcIntraEnbHo Timer

T304 Timer

HO Fails

HO Fails

HO Fails

CAC target CellFails for All TRBs

If the internal defence timer RrcIntraEnbHo expires without RRCConnectionReconfigurationComplete

reception, the handover procedure is failed the eNB initiates the S1 UE context release procedure.

Partial failure is supported.

So, only when all TRBs fail CAC (i.e. no TRBs can be established at target cell) will lead to HO cancel.

If at least one TRB succeeds (and at least one TRB fails) in RRM in target cell, the HO execution will continue.

The TRB that was successful in RRM will be handed over to the target cell and the failed TRB will be released.

In case the eNB is requested to release a non-existent radio bearer Id or a duplicate request to delete the

same radio bearer Id, the eNB should respond back with an appropriate cause value to indicate this.

If any UL RRC messge is received with integrity verification failure, the procedure is aborted, and the eNB

initiates the S1 UE context release procedure.






1.2.2 Inter eNB-X2 Mobility

MME SGW

X2

S1

RRC ConnectionNew

RRC Con

necti

on

• Pre-conditions:

The UE is RRC CONNECTED.X2 is setup towards the Target eNB

• Initial state:

SRB1/SIB2 + default bearer (+dedicated bearer) are established.

• Trigger:

The ENB receives a Measurement Report from the UE for event A3_intra-frequency mobility that indicates a potential target cell.

• Final state:

UE in RRC CONNECTED in the target cell: All bearers from the seNB are handed

over to the teNBUE context and associated resources are

deleted in the source cell

According to 3GPP an intra-LTE handover should not be triggered until the security is activated (“the UE only

accepts a handover message when security is activated”).

The eNB may trigger an intra-LTE handover only after the default bearer is established and security

activated Applicable eNB procedures:

X2-AP Handover preparation procedure

X2-AP SN status transfer procedure only if PDCP SN status preservation applies for at least one of the Radio Bearers handed over. This is applicable only to RB using RLC-AM mode

RRC Connection Reconfiguration (mobility) procedure

X2 U-plane data forwarding (if enabled via MIM configuration);

X2-AP UE CONTEXT RELEASE procedure

S1-AP path switch request procedure






1.2.2.1 Inter eNB-X2 Mobility: Handover Preparation

MME

Measurement Report

X2 Handover Request

SeNB teNB

Handover Decision withTarget Cell Selection

Setup UE context & associatedresources in the target cell

AS security algorithms selectionand key derivation

X2 Handover Request Acknowledge

Start Forwarding DLPackets to Target

RRC Connection ReconfigurationMeasurementConfiguration

RadioResourceConfigDedicatedMobilityControlInformation

UE Related Information security information

DL Data

DL Data Forwarding

Start Buffering DLPackets

DL Data

Handover Preparation

Phase 1: handover preparation: This phase involves the Source eNB, the target eNB and finally the UE.

In case of inter-eNB handover trigger, the Source eNB will initiate the X2-AP handover preparation providing in X2-AP HANDOVER REQUEST the necessary information to prepare the handover in the Target eNB.

If the data forwarding is enabled in the Source eNB then the Source eNB will propose to the target eNB to

perform DL data forwarding via X2.

The eligibility to DL forwarding of each supported QoS Label (QCI) is configured via MIM. If Integrity Protection and Confidentiality services are enabled, AS security data is also included in the X2 HANDOVER REQUEST message.

Target eNB prepares the handover based on the received request from the Source eNB and includes in

HANDOVER REQUEST ACKNOWLEDGE the RRC CONNECTION RECONFIGURATION message to be transmitted

transparently by the Source eNB to the UE.

If the data forwarding is enabled in the Target eNB then the Target eNB will accept the proposal from the

Source eNB to perform DL data forwarding via X2 by establishing the one DL X2 tunnel for each E-RAB subject to forwarding.

The eligibility to DL forwarding of each supported QoS Label (QCI) is configured via MIM. After this step the

target eNB is ready to receive UL transmission from the UE and DL data forwarded over X2 from the Source

eNB if configured previously.

If AS security services are enabled, the target eNB also derives keys that will be used for integrity

protection and ciphering.





1.2.2.1 Inter eNB-X2 Mobility: Handover Preparation

Handover Preparation Parameters

Parameter isDataForwardingAllowed dataForwardingForX2HoEnabled

Object ENBEquipment/ Enb/ ActivationService

Range & Unit Boolean [False, True] Boolean [False, True]

Class/Cat C / Fixed

Value TRUE OD True







1.2.2.2 Inter eNB-X2 Mobility: Execution and Completion

MME/SGW


SeNB teNB

DL Data

Start Transmitting DL Packets

Handover Execution



Handover Com

pletion

S1 Path Switch RequestUE Security Capabilities

S1 Path Switch Request Ack Security Context

Start buffering packets from S1

Transmit all DL X2 packets before S1 packets

X2 UE Context Release

Release UE context and associated resources

X2 Releaseresource

Phase 2: handover execution: This phase involves the UE, the Source eNB and the Target eNB- If data forwarding was configured in the handover preparation phase, the Source eNB forwards over X2 the

DL PDCP SDUs numbered but not acknowledged by the UE (only applicable for RLC-AM DRBs) followed by fresh REQUEST ACKNOWLEDGE reception and stops transmitting in the source cell the fresh unnumbered DL PDCP SDUs.

- When the UE receives RRC CONNECTION RECONFIGURATION in the source cell it will stop receiving/transmitting data in the source cell and will initiate synchronization to the target cell followed byrandom access procedure as indicated in the received message.

Both contention-based and non-contention based random access is supported. If resources are available the eNB allocates a dedicated preamble to the UE.

Phase 3: handover completion: This phase involves the the Source eNB, the Target eNB end the ePCWhen the Target eNB receives the RRC CONNECTION RECONFIGURATION COMPLETE it will send the S1-AP PATH SWITCH REQUEST to the MME to inform the that the UE changed the cell After the transmission of S1-AP PATH SWITCH REQUEST, the Target eNB is ready to receive DL data over S1 Upon request from the MME (at reception of S1-AP PATH SWITCH REQUEST), the SGW switches the DL data path to the Target eNB. The SGWsends one or more GTP-U End Marker per GTP-U tunnel through the old path (i.e. old S1 U-plane interface) to the Source eNB and then release the U-plane resources and confirms the path switch to the MME which in turnsends S1 PATH SWITH REQUEST ACKNOWLEDEGE to the Target eNB.

This message contains the security information for the NAS signalling messages that will have integrity protection. During the handover completion the UL data transmission occurs normally in the Source or the Target eNBif DL data forwarding was configured, the Source eNB continue to forward via X2 interface the received DL S1

packets until reception of GTP-U End Marker or resources are released DL data forwarding was configured, the Target eNB shall transmit the over the radio the DL X2 received packets until reception of X2 GTP-U End Marker or resources are released. Only after that DL S1 packets are transmitted.







MME/SGW

Measurement Report

SeNB teNB


Admission Control

DL Data


RrcIntraEnbHo Timer

HO Fails

X2 Handover Request

X2 Handover Request AcknowledgeAll eRAB teNB fail

Intra eNB Ho Canceled

X2 Handover Cancel

If at least one TRB is successful, the HO continues

S1 SetupNot completed successfully

S1 SetupNot completed successfully

Tcell is not available

Handover Preparation Failure

The incoming handover fails in the target eNB at the level of the HO preparation phase :1. If mobility is not enabled (i.e. configuration parameter isIntraFreqMobilityAllowed is not set to TRUE in MO

ActivationService) or if the cell is barred; in this case the Cause IE is set to Radio Network Layer Cause "Cell not Available"

2. If the S1 link to the MME identified by the GUMMEI information element is down or the S1 Setup procedure has not completed successfully; in this case the Cause IE is set to Radio Network Layer Cause "Cell not Available"

3. If the GUMMEI is unknown; in this case the Cause IE is set to Radio Network Layer Cause "Invalid MME Group ID" or "Unknown MME Code"

4. Or due to failure to establish the requested resources (admission control failure, eNB internal failure, RLC mode is not the same, etc); in this case the Cause IE is set to Radio Network Layer Cause "Cell not Available"






1.2.3 Inter eNB-S1 Mobility

MME SGW

S1

RRC ConnectionNew

RRC Con

necti

on

• Pre-conditions:

The UE is RRC CONNECTED.S1HoAllowed:: TrueThere is no X2 link between the two eNBs. Orthe target eNB is not connected to the MME currently serving the UE. Orthe operator has favored (through provisioning) S1 handover over X2 handover for this source to target eNB air.

• Initial state:

SRB1/SIB2 + default bearer (+dedicated bearer) are established.

• Trigger:

The eNB receives a measurement report for event A3_intra-frequency mobility that indicates a potential target cell.

In order to use S1 handover, the overall activation parameter “isIntraFreqMobilityAllowed” must be set to “true”. In addition, an activation flag isS1HoAllowed must also be set to activate S1 handover capability

As with X2 handover, an S1 handover is triggered by an A3 event trigger for which the measurement purpose is intra-LTE mobility. With the introduction of S1 handover, the eNB must decide whether to use X2 handover or S1 handover. The basic eNB logic is that the eNB will use S1 handover when X2 handover cannot be used. In addition, with

the ANR feature, the operator can favor S1 handover over X2 handover through the use of the “noX2HO”flag

The scenarios that lead to S1 handover being triggered are:

There is no X2-C interface setup towards the target eNB, or the X2-C interface is not available (e.g., SCTP down): The target eNB is not connected to the serving MME; The target eNB rejected the X2HO Request with an appropriate cause (e.g., invalid MME Group ID); Configuration data indicates a preference for S1 handover (i.e., “noX2HO” parameter introduced by ANR is set)






1.2.3.1 Inter eNB-S1 Mobility: Preparation

MME

Measurement Report

S1 Handover RequiredHandover Type & Target ID UE Context Information AS Information E-RABs List

SeNB teNB


Setup UE Context &Assoc Resources

Including UE Capabilities

DL Data


S1 HO RequestHandover Type (Intra LTE)

E-RABs to Setup List UE Security Capabilities

Security Context

S1 HO Request AcknoledgeE-RABs Admitted List E-RABs Failed to Setup List

Start BufferingForwarded Packet

S1 Handover CommandHandover Type & Target ID

E-RABs Subject to Forwarding List

E-RABs to Release List

RRCConnectionReconfiguration

mobility control informationsecurityConfigurationHO

handoverType = LTE S1 eNB Status Transfer

S1 MME Status Transfer






1.2.3.2 Inter eNB-S1 Mobility: Execution & Completion

MME

DL Data Forwarding

SeNB teNB

Start Forwarding DLPacket to Target eNB

DL Data

Random Access Preamble Random Access Response

Start Transmitting forwarded DL Packet to UE

DL Data

S1 HO Notification

DL DataDL Data ForwardingPossibly through SGW

Start buffering packet from S1

Start Transmitting forwarded DL Packet before S1 packets to UE

Path Switch

DL Data

Handover Execution and Com

pletion

S1 UE Context Release Command

Release data forwarding resourcesRelease UE context andassociated resources

S1 UE Context Release Complete







MME

Measurement Report

S1 Handover Required

SeNB teNB


DL Data

S1 HO Request

S1 HO Request Acknowledge

Start BufferingForwarded Packet

S1 Handover Command


S1 eNB Status Transfer S1 MME Status Transfer

HO Fails

TS1RelocPrepForS1Handover Timer

S1 Handover CancelS1 Handover Cancel Ack

S1UE Context Release Command

HO Fails

tS1RelocOverallForS1Handover

S1 UE Context Release CommandS1UE context Release Command

A timer , TS1RelocPrepForS1Handover, is introduced with S1 handover capability. This timer is started in

the source eNB when it sends the S1 HANDOVER REQUIRED message, and the timer is cancelled when the S1

HANDOVER COMMAND message is received from the MME. If the timer expires before the S1 HANDOVER

COMMAND message is received from the MME, then the source eNB sends an S1 HANDOVER CANCEL message to the MME, and expects to receive an S1 HANDOVER CANCEL ACKNOWLEDGE message in response from the MME.

The UE context is returned to its state prior to the handover trigger.

When the source eNB receives the S1 HANDOVER COMMAND from the MME, it starts timer

tS1RelocOverallForS1Handover. The timer is stopped when the source eNB receives the S1 UE CONTEXT

RELEASE COMMAND message from the MME. If the timer expires before the source eNB receives the S1 UE

CONTEXT RELEASE COMMAND message from the MME, then the source eNB sends an S1 UE CONTEXT RELEASE

REQUEST message. The expected result is that the MME will send an S1 UE CONTEXT RELEASE COMMAND

message to the source eNB, and the UE context will be released.






1.2.3.4 eNB-S1 Mobility Parameters

Parameter isS1HoAllowed dataForwardingForS1HoEnabled

directFwdPathAvailability

tS1RelocPrepForS1Handover

tS1RelocOverallForS1Handover

Object ENBEquipment/ Enb/ ActivationService ENBEquipment/ Enb/ S1AccessGroup/ S1Timers/ S1HoTimersConf

Range & Unit

Boolean [False, True] Integer ms [1 – 10000] step = 1

Class/Cat C / Fixed Optimization & TuningValue TRUE 4000






1.3 The Last Visited Information

During handover process, the the target eNB receives, either by X2 handover or by S1 handover, the “last visited cell information” IE coming from souce eNB.

The “last visited cell information” IE consists of the Cell Global ID (CGI), the cell size and the time the UE stayed in the cell.

FrequencyDense Urban/ Urban Suburban Rural

CellRadius Cell Size CellRadius Cell Size CellRadius Cell Size

Type I (2100) 1

SMALL

2.5

Medium

5

Large

Type III (1800) 1 2.5 6

Type IV (AWS) 1 2.5 6

Type VII (2600) 1 2 6

Type XII (700 Lower) 2 5 14

Type XIII (700 Upper) 2 5 14

Type XVII (700 Lower) 2 5 14

Type XX (EDD) 2 5 14






1.4 Intra-frequency Measurement Reporting Setting

S/PGW


SeNB

RRCConnectionReconfigurationMeasurementPurpose:: MobilityIntra Freq

Default SAE Bearer establishment and security activation



MeasurementPurpose ≠MobilityIntra Freq (If Any)

RRCConnectionReconfiguration:dlEARFCN offsetFreq (MeasObjectEUTRA)offsetFreq (LteNeighbouringFreqConf)neighCellConfig

The measurements are setup, modified or deleted in the UE using RRC signalling, more precisely the RRCConnectionReconfiguration message including the IE “MeasurementConfiguration”.

The measurements defined as intra-frequency LTE mobility triggers are configured as early as possible in the UE.

The handover strategy relies entirely on measurement reports from the UE.

The UE reports to the eNB when the handover trigger conditions are met. Upon receipt of the measurement

report the eNB is expected to trigger a handover procedure;

The measurements are setup, modified or deleted in the UE using RRC signalling, more precisely the

RRCConnectionReconfiguration message including the IE “MeasurementConfiguration”.


These measurements are identified by a measurement identity configured to measId and the attribute

MeasurementIdentityConf. measurementPurpose equal to “Mobility-Intra-Freq”






1.4.1 measurementPurpose Parameter


measurementPurpose: This parameter configures the purpose of this measurement reporting.

Parameter measurementPurpose Object ENBEquipment/ Enb/ RrmServices/ UeMeasurementConf/

MeasurementIdentityConfRange & Unit Enumerate [Mobility-Intra-Freq, Mobility-Iner-RAT-to-HRPD,

Automatic-Neighbor-Relation, Report-CGI, Leaving-Coverage-Alarm, Entering-Coverage-Alarm, Below-Serving-Floor, Mobility-Inter-RAT-to-UTRA, Mobility-Inter-RAT-to-GERAN, Mobility-Inter-Freq-to-EUTRA]

Class/Cat C- FixedValue OD

The measurements are setup, modified or deleted in the UE using RRC signalling, more precisely the

RRCConnectionReconfiguration message including the IE “MeasurementConfiguration”.


These measurements are identified by a measurement identity configured to measId and the attribute

MeasurementIdentityConf.measurementPurpose equal to “Mobility-Intra-Freq”

measObjectLink for MeasurementIdentityConf insance with measurementPurpose = 'Automatic-Neighbor-

Relation' can only be set to the same value as the measObjectLink for MeasurementIdentityConf instance with measurementPurpose = ‘Mobility-Intra-Freq’, where both MeasurementIdentityConf instances are pointed to by the same instance of RrcMeasurementConf.

measObjectLink for MeasurementIdentityConf insance with measurementPurpose = 'Report-CGI ' can only

set to the same value as the measObjectLink for MeasurementIdentityConf instance with measurementPurpose

= ‘Mobility-Intra-Freq’, where both MeasurementIdentityConf instances are pointed to by the same instance of RrcMeasurementConf.






1.4.2 RrcConnectionReconfiguration Parameters

Parameter dlEARFCN offsetFreq neighCellConfig Object ENBEquipment/

Enb/0RrmServices/UeMeasurementConf/MeasObject/MeasObjectEUTRA

ENBEquipment/ Enb/0 LteCell/ LteNeighboring/ LteNeighboringFreqConf

ENBEquipment/ Enb/RrmServices/UeMeasurementConf/ easObject/ MeasObjectEUTRA

ENBEquipment/ Enb/0 LteCell/ LteNeighboring/ LteNeighboringFreqConf

ENBEquipment/ ENb/0 LteCell/ LteNeighboring/ LteNeighboringFreqConf

Range & Unit

Integer [0..39649] step=1

Enumerate in dB [dB-24, dB-22, dB-20, dB-18, dB-

16, dB-14, dB-12, dB-10, dB-8, dB-6, dB-5, dB-4, dB-3, dB-2, dB-1, dB0, dB1, dB2, dB3, dB4, dB5, dB6, dB8, dB10, dB12, dB14, dB16, dB18, dB20, dB22, dB24, spare]

Enumerate in dB[NoMbsfnSubframesArePresent, DifferentUlDlAllocation]

Class/Cat C--New-set-ups / Fixed C--New-set-ups / Optimization - Tuning

Value OD dB0 [NoMbsfnSubframesArePresent, DifferentUlDlAllocation]

dlEARFCN: This parameter configures the RRC IE carrierFreq of MeasObjectEUTRAFDD IE

Note: dlEARFCN = 10 × ( - FDL_low ) + NOffs-DL [where FDL_low and NOffs-DL are some constants which

various with E-UTRA Band using for radio. is the central carrier frequency of the bandwidth.]

offsetFreq is used in the process Event A3 (Neighbor becomes offset better than serving) Ofs; it is used to

set both Ofs and Ofn.

The function of this parameter is to favor or not, HO between some specific neighboring frequencies.

offsetFreq: This parameter configures the RRC IE q-OffsetFreq, included in the SIB5.

The offset value is applicable to the carrier frequency. Not used for Intra frequency mobility.

neighCellConfig: This parameter advises the eNodeB of information related to MBSFN and TDD UL/DL

configuration of neighbor cells of this frequency.






1.5 Event A3 and HO Measurement

Event A3 (Neighbor becomes offset better than serving) : The UE shall: apply inequality A3-1, as specified below, as the entry condition for this event apply inequality A3-2, as specified below, as the leaving condition for this event

Inequality A3-1 (Entering condition)

Inequality A3-2 (Leaving condition)

Mn + Ofn + Ocn – Hys > Ms + Ofs + Ocs + Off

Mn + Ofn + Ocn + Hys < Ms + Ofs + Ocs + Off

Measurement Event3Mn

Mn-Hyst

Time To Trigger

Ms + Off

Ms

off

Hyst

Mn is the measurement result of the neighboring cell. Not taking into account any offsets.

Ofn is the frequency specific offset of the frequency of the neighbor cell (equals Ofs for intra-frequency

measurements and is included in MeasObjectEUTRA corresponding to the the frequency of the neighbor cell: offsetFreq, or including in LteNeighboringFreqConf if interfrequency mobility (SIB5) ).

Ocn is the cell specific offset of the neighbor cell. If not configured zero offset will be applied (included in LteNeighboringCellRelation of the serving frequency as parameter cellIndividualOffset corresponding to the frequency of the neighbor cell).

Ms is the measurement result of the serving cell, not taking into account any offset.

Ofs is the frequency specific offset of the serving frequency (i.e. offsetFreq within the MeasObjectEUTRAcorresponding to the serving frequency,or including in LteNeighboringFreqConf if interfrequency mobility (SIB5)).

Ocs is the cell specific offset of the serving cell (included in LteNeighboringCellRelation of the serving

frequency as parameter cellIndividualOffset), and is set to zero if not configured for the serving cell.

Hys is the hysteresis parameter for this event (i.e. hysteresis as defined within reportConfigEUTRA for this event).

Off is the offset parameter for this event (i.e. eventA3Offset (3GPP name:a3-Offset) as defined within

reportConfigEUTRA for this event).

Mn, Ms are expressed in dBm in case of RSRP, or in dB in case of RSRQ.

Ofn, Ocn, Ofs, Ocs, Hys, Off are expressed in dB.






1.6 Measurement Configuration Model

RrcMeasurement

Conf

UeMeasurement

Conf

MeasObjecteUTRA

MeasObjectUTRA

MeasObjectcdma2000

MeasObjectGERAN

ReposrtConfigGERAN

ReposrtConfigCDMA2000

ReposrtConfigUTRA

ReposrtConfigeUTRA

LteCell

Measurement IdentityConf

ReposrtConfig MeasObject

In each cell, the UE measurements configuration (i.e. the list of one or more measurement identities and

their related measurement configuration parameters) is provided by the MO RrcMeasurementConf.

Each measurement (i.e. measurement identity and its related configuration parameters) is defined by one

instance of the MO MeasurementIdentityConf.

Each instance of the MeasurementIdentityConf together with associated MOs ReportConfig and

MeasObject form a complete configuration of one RRC measurement configuration.

One instance of the MO MeasurementIdentityConf is a profile of one RRC measurement configuration.

In the eNB one or more profiles (instances of MeasurementIdentityConf) could be configured.

The profiles are shared in the cells under the eNB among the measurement configurations

(RrcMeasurementConf).






1.6.1 sMeasure, trigger/reportQuantity Parameters

sMeasure : This parameter configures the RRC IE s-Measure used to define the serving cell quality threshold controlling whether or not the UE is required to perform measurements of intra-frequency, inter-frequency and inter-RAT neighboring cells.

triggerQuantity: This parameter configures the RRC IE triggerQuantity included in

the IE reportConfigEUTRA in the MeasurementConfiguration IE

reportQuantity: This parameter configures the RRC IE reportQuantity included in the IE reportConfigEUTRA in the MeasurementConfiguration IE

Parameter sMeasure triggerQuantity reportQuantityObject ENBEquipment/Enb/RrmServi

ces/UeMeasurementConf/RrcMeasurementConf

ENBEquipment/ Enb/ RrmServices/ UeMeasurementConf/ ReportConfig/ ReportConfigEUTRA

Range & Unit

Integer in dBm [-140 .. -43] step = 1

Enumerate [rsrp, rsrq]

Boolean [sameAsTriggerQuantity,

both]Class/Cat C--New-set-ups /

Optimization - Tuning C--New-set-ups / Fixed

Value -43 rsrp sameAsTriggerQuantity

For all mobility related measurements, triggerQuantity may be set to RSRP in ReportConfigEUTRA/0 and/or

RSRQ in ReportConfigEUTRA/1.

If both measurements are activated, the measurement which trigger the HO is the one first met the HO

criterions

· ALU Internal: The recommended value for triggerQuantity is RSRP for all mobility related measurements.

· For ‘Automatic-Neighbor-Relation’ trigger, triggerQuantity can only be set to ‘rsrp’.






1.6.2 hysteresis and timeToTrigger Parameters

hysteresis: This parameter defines the hysteresis used by the UE to trigger an intra-frequency or blind Inter-RAT event-triggered measurement report.

The value sent over the RRC interface is twice the value configured (the UE then divides the received value by 2).

timeToTrigger : This parameter defines the period of time during which the conditions to trigger an event report have to be satisfied before sending a RRC measurement report in event triggered mode

Parameter hysteresis timeToTrigger Object ENBEquipment/ Enb/ RrmServices/ UeMeasurementConf/

ReportConfig/ ReportConfigEUTRA Range & Unit dB

[0.0..15.0] step = 0.5 Enumerate, ms [ms0, ms40, ms64, ms80, ms100, ms128, ms160, ms256, ms320, ms480, ms512, ms640, ms1024, ms1280, ms2560, ms5120]

Class/Cat C--New-set-ups / Optimization - Tuning Value 2dB 40ms

Note: hysteresis is used in several process: Event A3 (Neighbor becomes offset better than serving); Event A2 (Serving becomes worse than threshold); Event A1 (Serving becomes better than threshold); Event A4

(Neighbor becomes better than threshold); Event A5 (Serving becomes worse than threshold1 and neighbor

becomes better than threshold2).

When triggerTypeEutra is set to ‘eventA3’, triggerQuantity is set to ‘rsrp’, the recommended value from

performace testing team for hysteresis is 2.0 dB.

When triggerTypeEutra is set to ‘eventA5’, triggerQuantity is set to ‘rsrp’, 4G OPENED recommended value for hysteresis is 2.0 dB.

When triggerTypeEutra is set to ‘eventA1’, triggerQuantity is set to ‘rsrp’, 4G OPENED recommended value for hysteresis is 2.0 dB.

For ‘Automatic-Neighbor-Relation’ trigger, hysteresis should be set to the same value as the hysteresis

(corresponding to triggerQuantity = ‘rsrp’ if it exists; otherwise, corresponding to triggerQuantity = ‘rspq’)

used for ‘Intra-frequency-handover-trigger’.

For ‘Report-CGI’ trigger, hysteresis is not used but must not be left unset.

Rule: timeToTrigger :

For ‘Automatic-Neighbor-Relation’ trigger, timeToTrigger can only be set to the same value of the

timeToTrigger (corresponding to triggerQuantity = ‘rsrp’ if it exists; otherwise, corresponding to

triggerQuantity = ‘rspq’) used for ‘intra-frequency-handover-trigger’.

For ‘Report-CGI’ trigger, timeToTrigger is not used but must not be left unset.

timeToTrigger is used in several process: Measurement identity removal; Measurement identity addition/

modification; Measurement object removal; Measurement object addition/ modification; Reporting

configuration removal; Reporting configuration addition/ modification; Quantity configuration; in general in

Measurement report triggering; Measurement related actions upon handover and re-establishment






1.6.3 maxReportCells Parameter

maxReportCells: This parameter configures the RRC IE maxReportCells included in the IE reportConfigEUTRA in the MeasurementConfiguration IE

ParametermaxReportCells

Object ENBEquipment/ Enb/RrmServices/UeMeasurementConf/ ReportConfig/ ReportConfigEUTRA

Range & Unit integer [1..8] step = 1


Value 8

This parameter allows UE to report up to number of maxReportCells neighbor cells in each

MeasurementReport message. UE may include less than maxReportCells neighbor cells in the

MeasurementReport message based on environment (e.g. how many neighbor cells actually exist) and the

settings of other measurement configuration parameters (e.g. how many neighbor cells are good enough to

trigger the report based on measurement configuration).

For all mobility related measurements, the default value of the corresponding maxReportCells is set to ‘1’.

Setting the parameter to a value greater than ‘1’ will not be useful currently. This is because in the current

target cell selection algorithm, only the best neighbor cell will be considered as the handover target. The

setting of the parameter will need to be updated once more candidate cells are considered in handover target selection.

For ‘Automatic-Neighbor-Relation’ trigger, the value of the corresponding maxReportCells should be set to the maximum value of ‘8’. This is to ensure UE to report as many new neighbor cells as possible in a short

time.






1.7 Automatic Neighbor Relation (ANR)

The Automatic Neighbor Relation (ANR) Configuration and Optimization feature are for the eNB cells to automatically create and update their neighbor relations.

ANR will minimize the need for the manual provisioning of the neighbor relations by operators.

More important, the ANR feature provides more accurate neighbor relations than the manual method.

Neighboring Relation

OAM controlledNR Attributes

NR LCellID

TCI No Remove

No HO

No X2

1 LCI#1 TCI#1 √

2 LCI#1 TCI#2 √

3 LCI#1 TCI#3 √

X2 Management

Setup X2

O&M

ANR Function

Neighbor Removal Function

Neighbor Detetion Function

NR TableManagement

Function

Internal Information

NR Remove

NR Add

ANRUpdate

Neighbor Relation Attributes Update

Neignbor RelationUpdate

RRC

Measurement Report/Request

Handover

32

2

1

1

54

The ANR feature includes the ANR neighbor relation creation function, the ANR neighbor relation

maintenance function, the ANR synchronization function and the ANR reset function.

The ANR neighbor relation creation function builds up the neighbor relations by requesting the UEs to

search for neighbor cells or by receiving the neighbor relations from the neighbor eNB.

The ANR neighbor relation maintenance function deletes the obsolete neighbor relations and obsolete X2

links.

With ANR, the neighbor relations are created and constantly updated based on the actual measurement

and report from UE. Therefore, for a well implemented ANR feature, the neighbor relations will only include the neighbor cells that are good target candidates for handover.

The goal of ANR is to manage neighbour relation. Since OAM also has some restrictions on neighbour

relation due to the requirements of operators, ANR also needs to consider the restrictions from OAM. So how to describe the neighbour relation based on the restrictions and how to manage the neighbour relation is a question ofimplementation.

The Neighbour Relation Detection procedure could be as as follows:

0. Neighbour Detection Function instructs RRC to measure the cells on some certain frequency or in

another RAT.

1. RRC forwards the measurement reports to Neighbour Detection Function.

2. Neighbour Detection Function decides to add a new Neighbour Relation.

3. Neighbour Relation Table Management Function updates the Neighbour Relation Table.

4. Neighbour Relation Table Management Function sends the updated Neighbour Relation through some

standard interface to OAM.

5. OAM will ask Neighbour Relation Table Management Function to update the Neighbour Relation

Attributes if necessary.






1.7.1 ANR Phases

ANR Idle

ANR Active Phase

ANR Wakeup phase

ANR activation& (LTE Cell>anrstate

=complete)

ANR activation& (LTE Cell>anrstate=

Not complete)

ANR deactivation

ANRdeactivation

ANR Dormant

Phase

HO meas report wt Best PCI being unknown

HO eas report w/t best PCI being unknown

Nb PCI meas > Threshold 1 &Nb PCI meas w/o unknown PCI> threshold

Dormat Phase Timer for ecgDiscovery Timeout

Or ECGI for unknown PCI received

ANRdeactivation

1

2

3’

3”

4’

5’4””

4” 5”

The ANR feature activation (ActivationService::anrEnable) is controlled on per eNB basis.

When ANR is activated, each of its cells can be in one of the three phases independently, ANR active phase,

ANR dormant phase and ANR wake-up phase

An “active” phase, which is triggered at first ANR activation and aims at pro-actively search new

neighbours by soliciting all establishing UEs that will then all participate to the ANR task.

A “dormant” phase, following the active phase, in which ANR function is no longer configuring any specific measurements.

Transition from active to dormant phase is triggered when thresholds, defined in terms of UE measurement reports received, are crossed.

A “wake-up” phase, which is triggered by a UE reporting (through mobility measurement) an unknown

neighbour. ANR behaviour in this phase is quite similar to the one in the active phase, with differences being that the aim is only to look at one particular neighbour and the duration of the wake-up phase is limited.

A “garbage collection” period during which the ANR function will remove obsolete neighbour relations

(meaning never used for mobility) and associated X2 links. Garbage collection is launched periodically.






1.7.2 ANR Activation

ANR feature is activated by setting anrEnable parameter to True. This parameter can be set to 'True' only if licensing (Tokens) are available for

the feature. The total number of activations for each feature is counted across all eNBs by SAM.

Parameter anrEnable Object ENBEquipment/ Enb/ ActivationServicRange & Unit Boolean [false, true] Class/Cat C – Immediate Propagation / Fixed

When setting anrEnable to ‘True’: Each LteCell instance served by the eNB must add a reference (through rrcMeasurementconfId attribute) to an instance of RrcMeasurementConf that references (through

measurementIdentityConfIdList attribute) one and only one instance of MeasurementIdentityConf with

measurementPurpose set to ‘Automatic-Neighbor-Relation’.

LteCell instance served by the eNB must add a reference (through rrcMeasurementConfId attribute) to an instance of RrcMeasurementConf that references (throughmeasurementIdentityConfIdList attribute) an

instance of MeasurementIdentityConf with measurementPurpose set to ‘Report-CGI’.






1.7.3 ANR Neighbor Relation Creation Function

eNB A

eNB B

Cell BPCI = 5

ECGI = 19Cell APCI = 3

ECGI = 17

Report ANR meas (PCI = 5)2

Configure reportCGI (PCI 5)

3 Report ECGI (ECGI = B)4

Configure ANR meas

Read SIB1 t

o get E

CGI1

1

Request B IP @

5

Request B IP @

6

Provide B IP @ Provide B IP @

7

8

Establish SCTP and X2 link9

MME

When Cell A is in ANR active phase, eNB A will send ANR measurement configuration to all UEs that are in

RRC connected state in Cell A to search for neighbor cells.

UE will send a measurement report with Cell B’s PCI when triggered by ANR measurement configuration.

If eNB A does not know the ECGI associated with the reported PCI, it will direct UE to read from PBCH of

Cell B to obtain the ECGI.

UE finds out the ECGI of Cell B, it will report back to eNB A.

UE can detect Cell B’s PCI and makes reference signal measurements directly. Since the neighbor eNB ID

used for X2 link setup is not contained in PCI but in ECGI, eNB A has to direct the UE to read Cell B’s PBCH for its ECGI if it does not know the ECGI associated with the PCI.

In order for the UE to read PBCH of Cell B, eNB A will force the UE into DRX cycle.

After ECGI of Cell B is received, if the X2 link does not already exist between eNB A and eNB B, ANR will

attempt to set up the X2 link .

X2 link may already exist if any cell in eNB A already has a neighbor relation with one or more cells in eNB.





1.7.3 ANR Neighbor Relation Creation Function

1.7.3.1 Neighbor Relation Process

Neighbor relations are used in a cell to route the handover request. When a UE reports the PCI of a handover target candidate cell, source cell will check the stored neighbor relations to find out whether the X2 link exists between the source eNB and the target eNB.

If the X2 link exists, and X2 handover is permitted, source eNB will initiate the X2 handover procedure.

If X2 link does not exist, or X2 handover is not permitted, but S1 handover is possible, S1 handover will be attempted.

Otherwise, the handover request will be discarded.

NR LCellID

TCI No Remove

No HO

No X2

1 LCI#1 TCI#1 √

2 LCI#1 TCI#2 √

3 LCI#1 TCI#3 √

4 LCI# TC#5

PCI#3

PCI#2

PCI#6

PCI#8

PCI#5

PCI#7

Repo

rt PC

I#4

There are four stages in the addition of a neighbor to the neighbor cell list:

1. Discovery of an unknown PCI in either of the following manners:

The PCI is reported by the UE in its measurements (ANR or mobility)

The PCI (and ECGI) is obtained from X2 Setup or X2 Enb Configuration Update

Note: it is not possible to learn a PCI through an incoming S1 Handover

2. Association of a CGI to the PCI:

By requesting one or several UEs to report the ECGI associated to the PCI

By X2 Setup or X2 eNB Configuration Update

Note: the PCI -> CGI relation may not be unique (cf. PCI Confusion management)

3. Retrieval of the X2 IP address

4. X2 Setup

Of course, neighbor cells do not all go through the 4 steps.






Main Parameters Included in Neighbor Relation [cont.]

A summary is provided below on how ANR will set the parameters in the LteNeighboringCellRelation for an automatically created instance of neighbor relation:

Parameter Description

cellIndividualOffset It indicates the cell individual offset of the neighbor cell provided to UE in connected mode to perform measurement

noHoOrReselection It indicates whether handover to the neighbor cell is permitted. It is set to the default value of ‘false’ indicting handover is permitted

physicalLayerCellIndentityGroupIndex

It indicates the physical layer cell identity group. It is calculated from PCI of the neighbor cell

physicalLayerCellIndentityIndex

It indicate the physical layer cell identity. It is calculated from PCI of the neighbor cell

trackingAreaCode It is used to identify the tracking area within the scope of a PLMN. It is reported by UE or received from neighbor eNB through X2 messages

x2AccessId It refers to the instance of X2Access MO that represents the X2 link to the eNB of the neighbor cell

relativeCellIdentity Is the rightmost 8 bits of the E-UTRAN Cell Identifier contained in ECGI of the neighbor cell

qOffsetCell It indicates the offset between the serving cell and the neighbor cell. It isprovided to UE in idle mode to perform cell reselection.

For a neighbor relation created by ANR, cellIndividualOffset, noHoOrReselection, noRemove and qOffsetCell

are always set to default values by ANR.

It is up to the operator to change them to non-default values based on different needs.






Main Parameters Included in Neighbor Relation

Parameter measuredByAnr noRemoveObject ENBEquipment/ Enb/ LteCell/

LteNeighboring/LteNeighboringFreqConf/LteNeighboringCellRelationRange & Unit Boolean [false, true] Class/Cat N.A. / Fixed

Value True, if Neighbor Relation is createdby ANR function or provisioned throughOMC and is detected by ANR functionafterwards. False, if Neighbor Relation is

provisioned though OMC and has not been detected by ANR function.

False

• measuredByAnr: This parameter indicates the neighbor relation is created by the ANR function or is created by the operator and is detected by ANR function afterwards.• noRemove: This parameter indicates whether the neighbor relation can be removed by the ANR garbage collection function. It is set to the default value of ‘false’ indicating it can be removed by the ANR garbage collection function.

noRemove parameter, indicates whether the LteNeighboringCellRelation is allowed to be removed by the

ANR garbage collection function.

If ‘noHoOrReselection’ is set to ‘True’, the ‘noRemove’ must also be set to ‘True’ for the same

LteNeighboringCellRelation instance to make the neighbor relation belong to the HO black list.






1.7.4 ANR Measurement Configuration

Three events can be used to trigger the UE to send an ANR measurement report. They are:

• Event A3: when the neighbor cell becomes a given offset better than the serving cell. • Event A4: when the neighbor cell becomes better than a given absolute threshold.• Event A5: when the serving cell becomes worse than a given threshold and the

Event A3, A4 or A5 each has its own entering condition(s) and leaving condition(s) as listed below:

• Event A3Mn - hysteresis > Ms + eventA3Offset • Event A4 Mn+ offsetFreq - hysteresis > thresholdEutraRsrpor thresholdEutraRsrq• Event A5 Ms+ hysteresis < thresholdEutraRsrpor thresholdEutraRsrqand Mn+ offsetFreq – hysteresis > threshold2EutraRsrp or threshold2EutraRsrq

• Event A3: Mn+ hysteresis < Ms + eventA3Offset • Event A4 :Mn+ offsetFreq + hysteresis < thresholdEutraRsrpor thresholdEutraRsrq• Event A5 :Ms–hysteresis > thresholdEutraRsrpor thresholdEutraRsrq or Mn+ offsetFreq + hysteresis < threshold2EutraRsrp or threshold2EutraRsrq

At any given time, only one of the above three triggers can be used for ANR measurement configuration.

The selection is made through ReportConfigEUTRA::triggerTypeEUTRA.

Event A3 is recommended for ANR measurement configuration. Event A4 and Event A5 are also available for

trial and testing.

Event A3, A4 or A5 each has its own entering condition(s) and leaving condition(s) as listed below. For a

selected event, only when the entering conditions are continuously satisfied for

ReportConfigEUTRA::timeToTrigger ms, a UE will send the first measurement report to the eNB. UE may also be directed to send multiple duplicated measurement reports (up to ReportConfigEUTRA::reportAmountreports with interval ReportConfigEUTRA::reportInterval) in the duration when the entering conditions are continuously satisfied.

Mn is the measurement result of the neighbor cell. Ms is the measurement result of the serving cell.

Mn, Ms are in unit of dBm if RSRP is used or dB if RSRQ is used. offsetFreq is a parameter defined in MeasObjectEUTRA MO.

All other parameters used in the event entering or leaving inequalities are defined under ReportConfigEUTRA MO.






1.7.5 Set Up X2 Links

Setting up X2 link is essential to create a neighbor relation. There are three steps for this procedure:

1. Automatically retrieve the X2 IP address of the eNB B from MME through S1procedure

2. Set up SCTP association between eNB A and eNB B 3. Establish X2 link between eNB A and eNB B

Local eNB MME Distant eNB

eNB CONFIGURATION TRANSFER(Source Global eNB ID & TAI, Target Global eNB ID & TAI,

SON information request) MME CONFIGURATION TRANSFER

MME CONFIGURATION TRANSFER (Source eNB ID & TAI, Target eNB ID & TAI, SON information

reply = 1 or 2 transport address(es) )

eNB CONFIGURATION TRANSFER

The direct X2 handover provides better performance than S1 handover in general as S1 handover has to go

through SGW which normally takes much longer time.

Once a new PCI is detected and its ECGI is found, ANR on eNB A will automatically attempt to establish

the X2 link to neighbor eNB B if the X2 link does not already exist.






1.8 Inter-Frequency RRC Connected Mode Mobility

Intra-LTE, inter-frequency (same band or different bands) UE RRC connected mode mobility - redirection or handover to a target cell having the same frame structure (FDD to FDD or TDD to TDD). Intra-LTE, inter-frequency RRC connected mode mobility is activated When ActivationService::isInterFreqEutraSameFrameStructureMobilityAllowed is set to ‘True’

UE MME

Release UE context/resource

Target FrequencySelection

Measurement ReportmeasIdmeasResultServCell

RRCConnection ReleaseredirectedCarrierInfo

UE reselects to a cellTarget frequency

eNB

S1AP UE Context Release Request

S1AP UE Context Release Command

S1AP UE Context Release Complete

Intra-LTE, inter-frequency redirection can be performed blindly (without UE measurement of the target

frequency/cell) or measurement based (based on UE measurement of the target frequency/cell).

Blind redirection will be performed when the UE enters bad serving condition area and it

sends event A2 measurement report with measurementPurpose set to ‘Below-Serving-Floor’ In this case,

eMCTA algorithm will determine the target RAT/carrier to perform the blind redirection.

If a EUTRA carrier is selected as the new target, an inter-frequency blind redirection will happen





2 Inter-RAT Mobility: eUTRAN-UTRAN






2.1 RRC Idle Mode Mobility: Cell Reselection

Cell reselection to UTRA is activated when ActivationService::isMobilityToUtraAllowed is set to ‘True’.

Parameter isMobilityToUtranAllowed


Range & Unit Boolean [false, true]

Class/Cat C – New-set-ups / Fixed

ValueCan be set to 'True' only if licensing (Tokens) are available for the feature.The total number of activations for each feature is counted across all eNBs by SAM.

UMTS

LTE

SiB 3 & SiB 6

eUTRAN to UTRAN provides basic mobility capability for UE moving from LTE radio coverage to UMTS radio

coverage. This feature enables the LTE-to-UMTS mobility for a multi-mode UEs in RRC idle mode. This feature allows a UE to leave the LTE coverage (island or hot-spot or hot-spots cloud) to recover the service in the UMTS coverage; as soon as the UMTS coverage gets available i.e. inter-RAT measurement demonstrate that the UMTS radio conditions are sufficiently good.

When reselection to UTRA is activated, eNB will broadcast (SIB6) in addition to (SIB3) to support UE for LTE to UTRA cell reselection in RRC idle mode.







When camped normally, the UE shall perform the following tasks:Select and monitor the indicated Paging Channels of the cell according to information

sent in system information.Monitor relevant System Information.Perform necessary measurements for the cell reselection evaluation procedure.Execute the cell reselection evaluation process on the following occasions/triggers:

UE internal triggers.When information on the BCCH used for the cell reselection evaluation procedure has been modified.

PCH (S

IB)SIBs

Measurements






2.1.1 Cell Reselection Algorithm Description [cont.]

The S criterion is again used to select the good cells for cell reselection, but with the

parameters broadcasted in SIB6.

The cell selection criterion S (Calculated by the UE) is fulfilled when:

Srxlev > 0 & Squal > 0

Where:

Srxlev = Qrxlevmeas – (Qrxlevmin + Qrxlevminoffset) - Pcompensation

And:

Squal = Qqualmeas – (Qqualmin + QqualminOffset)

The signalled value QrxlevminOffset is only applied when a cell is evaluated for cell selection as a result of a periodic search for a higher priority PLMN while camped normally in a VPLMN [R14]. During this periodic

search for higher priority PLMN the UE may check the S criteria of a cell using parameter values stored from a different cell of this higher priority PLMN.

Srxlev: Calclated by the UE: Cell Selection RX level value (dB).

Squal: Calculated by the UE: Cell Selection quality value (dB) Applicable only for FDD cells.

Qrxlevmeas: Measured by the UE: Measured cell RX level value (RSRP).

Qrxlevmin: CellSelectionReselectionConf::qRxLevMin or CellReselectionConfUtraFdd::qRxLevMin Minimum

required RX level in the cell (dBm). SIB6 for the target cell.

Qrxlevminoffset : CellSelectionReselectionConf::qRxlevminoffset: Offset to the signalled Qrxlevmin taken into account in the Srxlev evaluation as a result of a periodic search for a higher priority PLMN while camped normally

CellReselectionConfUtraFdd::qQualMin: Minimum required quality level in the cell (dB).

Applicable only for FDD cells.SIB6 in inter-working with 3G SIB3 Qqualmin.

Qqualmin: Not yet implemented: Offset to the signalled Qqualmin taken into account in the Squal evaluation as a result of a periodic search for a higher priority PLMN while camped normally in a VPLMN.

Not yet implemented: QqualminOffset Pcompensation Max (pMaxUTRA – Pumax, 0) (dB).






2.1.1.1 Limit the UTRA FDD Measurement

Snonintrasearch : This parameter specifies the threshold (in dB) for inter frequency and

inter-RAT measurements.

Configuration parameter name is sNonIntrasearch

If SServingCell > Snonintrasearch:

UE may choose not to perform measurements of inter-RAT frequency cells of equal or

lower cellReselectionPriority.

If SServingCell <= Snonintrasearch, or if sNonIntrasearch is not sent in SIB3 in the serving cell:

The UE shall perform measurements of inter-RAT frequency cells of equal or lower

cellReselectionPriority

RSRP of serving Cell

At least detected: 60 sec* N layers

≤

Qrxlevmin + QrxlevminOffset+ Snonintrasearch

NUTRA_Carrier) * 30 sec

Higher Priority

All Priority cellt

In order to further restrict the amount of measurement carried out by the UE in RRC-Idle mode, The UE shall apply the following rules for inter-RAT UtraFdd frequencies, which are indicated in in SIB6 and for which the UE has cellReselectionPriority: For inter-RAT UtraFdd frequency, with a cellReselectionPriority higher than the cellReselectionPriority of the current E-UTRA frequency, the UE shall perform measurements of higher priority inter-RAT UtraFdd frequencies.

For inter-RAT UtraFdd frequency, with cellReselectionPriority lower than the cellReselectionPriority of the

current E-UTRAN frequency






2.1.1.2 Cell Reselection Related Parameters

Parameter qRxLevMin pMaxUTRAObject ENBEquipment/ Enb/ LteCell/ UtraNeighboring/

UtraFddNeighboringFreqConf/ CellReselectionConfUtraFdd

Range & Unit Integer in dBm[-119..-25] step = 2

Integer in dBm[-50..33] step = 1

Class/Cat C – Immediate Propagation /Optimization - Tuning Value -115 dBm 24dBm

recommended value is -115 dBm

OB UMTS Class1 Class2 Class3 Class4

2100Mhz +33 °27 +24 +21

1900Mhz NA NA +24 +21

850Mhz NA NA +24 +21

850Mhz NA NA +24 +21

900 Mhz NA NA +24 +21

qRxLevMin : 3GPP 36.331[R08] Minimum required RX level in the UMTS cell (dBm) . This parameter configures the q-RxLevMin included in the SystemInformationBlockType6. The value sent over the RRC interface is computed by substracting 1 to the configured value and dividing by 2 (the UE performs the opposite computation, i.e. IE vale * 2 + 1) Changing this value will affect cell size in terms of re-selection area toward UMTS.

Increasing this value will lead the mobile to start cell-selection/re-selection procedure sooner and then will

artificially decrease cell size in idle mode.

pMaxUTRA : TS36.331: this parameter configures the p-MaxUTRA included in the IE SystemInformationBlockType6

Pcompensation = max(PEMAX - PUMAX, 0)

Where: PEMAX = pMaxUTRA

PUMAX = maximum UE output power (dBm) according to its power class in 3g and operating band.






2.1.1.2 Cell Reselection Related Parameters [cont.]

sNonIntraSearch: Threshold for serving cell reception level under which the UE must

trigger inter-frequency and inter-RAT measurements to cells of equal or lower priority

for cell reselection .

The value sent over the RRC interface is half the value configured (the UE then

multiplies the received value by 2).

Broadcast in SystemInformationBlockType3

Parameter sNonIntraSearch

Object ENBEquipment/ Enb/ LteCell/ CellSelectionReselectionConfRange &

UnitInteger in dB [0..62] step = 2

Class/Cat C - Immediate Propagation / Optimization - Tuning Value For better performance, we recomend to do measurements earlier.

The value 16 is the recommended value

If the SservingCell of the E-UTRA serving cell (or other cells on the same frequency layer) is greater

than Snonintrasearch then :

the UE may not search for, or measure inter-RAT layers of lower priority.

the UE search for inter-RAT layers of higher priority at least every Thigher_priority_search = (60 * Nlayers) seconds, where Nlayers is the total number of configured higher priority E-UTRA, UTRA FDD, UTRA TDD, CDMA2000 1x and HRPD carrier frequencies and is additionally increased by one if one or more groups of GSM frequencies is configured as a higher priority.






2.1.1.2 Cell Reselection Related Parameters [cont.]

Parameter qQualMinObject ENBEquipment/ Enb/ LteCell/ UtraNeighboring/

UtraFddNeighboringFreqConf/ CellReselectionConfUtraFddRange & Unit Integer in dB [-24..0] step = 1

Class/Cat C – Immediate Propagation / Optimization - TuningValue Recommanded Value is 16dB

Measurementzones:

Qqualmeas>Qqualmin

Qrxlevmeas>Qrxlevmin(SIB6)+Qrxlevminoffset+Pcompensation

Qqualmeas>QqualminandQrxlevmeas>Qrxlevmin(SIB6)+Qrxlevminoffset+PcompensationQqualmin

Qrxlevmin (SIB6)+Qrxlevminoffset + P compensation

CPICH RSCP

CPICH Ec/Io

When the measurement rules indicate that UTRA FDD cells are to be measured, the UE shall measure

CPICH Ec/Io and CPICH RSCP of detected UTRA FDD cells in the neighbor cell list at the minimum

measurement rate in relationship with Enb::defaultPagingCycle.

In inter-working with the value of Enb::defaultPagingCycle, which is rf32, Measures occur at least:

(NUTRA_carrier) * [5.12 sec]

NUTRA_carrier: number of carriers used for all UTRA FDD cells in the neighbor cell list.






2.1.1.3 Cell Reselection Priorities Handling

Absolute priorities of different E-UTRAN frequencies or inter-RAT frequencies may be provided to the UE in the:

System information orin the RRCConnectionRelease message releasing the RRC connectionor by inheriting from another RAT at inter-RAT cell (re)selection.

If UE is in camped on any cell state, UE shall only apply the priorities provided by system information from current cell.

The UE shall only perform cell reselection evaluation for E-UTRAN frequencies and inter-RAT frequencies that are given in system information and for which the UE has a priority provided.

NOTE: Equal priorities between RATs are not supported.

GSM

UMTSLTE

In the case of system information, an E-UTRAN frequency or inter-RAT frequency may be listed without providing a priority .If priorities are assigned via provided in dedicated signalling, the UE shall ignore all the priorities provided in

system information.






2.1.1.3 Cell Reselection Priorities Handling [cont.]

cellReselectionPriority: this parameter contributes to the configuration of the

IE IdleModeMobilityControlInfo freqPriorityListUTRA-FDD (Optional).

Parameter cellReselectionPriority

ObjectENBEquipment/ Enb/ LteCell/ UtraNeighboring/ UtraFddNeighboringFreqConf/ CellReselectionConfUtraFdd

Range & Unit Integer [0..7] step = 1 Class/Cat C – Immediate Propagation / Optimization - Tuning

Value OD

In general, LTE system is preferred over UTRAN and UTRAN is preferred over GERAN for better performance.

So it is recommended to set CellReselectionConfLte::cellReselectionPriority >

CellReselectionConfUtraFdd::cellReselectionPriority > CellReselectionConfGeran::cellReselectionPriority






2.2 RRC Connected Mode Mobility: Redirection

LA3.0 supports LTE-to-UMTS mobility in RRC connected mode with blind redirection

or event B2 measurement based redirection.

Compared with a blind redirection without inter-RAT UTRA-FDD radio measurements,

the redirection with measurement improves the end-user QoE (Quality of Experience)

by redirecting the UE from an LTE island/hot-spot to an UMTS overlay in a timely

fashion.

UMTS

LTE

Redirection to UMTS Cell

The redirection with measurement avoids the UE from being stuck in an LTE source cell with bad radio

conditions and allows the UE being redirected towards an UMTS target cell with good radio conditions.






2.2.1 eUTRA To UTRA Redirection Procedure

MME

Control Procedure for mobility

Release/Cell redirection Execution PhaseRRC Connection Release

releaseCause:: OtherredirectedCarrierInfo:: utra-FDD

idlemodeMobilityControlInfo::freqPriorityListUTra-FDD

Of FreqPriorityUTRA-FDD

S1-AP UE Context Release RequestMME UE S1AP IDeNB UE S1-AP IDCause=InterRat Mobility

Redirection InformationTo Target RAT with RRC Connection

Relaese:UE leaves EUTRAN Old Cell & start Access Target RAT new cell

The UE Shall1- if the RRCConnection Release messageIncludes the idleModeMobilityControlInfo2-Store the cell reselection priority information Provided by the idle modemobility controlinfo;>Else:2-Apply the cell reselection priority information broadcastIn the system information

EXECUTION PHASE:

During the previous phase (selection of the control procedures for mobility), the source ENB has decided to initiate a EUTRA-to-UTRA-FDD redirection to the target access network (UTRA-FDD).

The source ENB will give a command to the UE to re-select a cell in the target access network via the RRC CONNECTION RELEASE. The RRCConnectionRelease message is used to command the release of an RRC connection.

The eNodeB builds the RRCConnectionRelease message with the redirectionInformation, so that the UE

select a suitable cell on the UTRA-FDD frequency indicated by the redirectionInformation in accordance with the usual cell selection process.

The eNodeB may provide IRAT/frequency priority information during RRCConnectionRelease message with

the redirectionInformation.

The eNodeB builds the RRCConnectionRelease message; with the idleModeMobilityControlInfo (optional) so that the UE stores the cell reselection priority information provided by the idleModeMobilityControlInfo; or without the idleModeMobilityControlInfo (optional) so that the UE applies the cell reselection priorityinformation broadcast in the system information

The source ENB sends an S1AP UE CONTEXT RELEASE REQUEST message to the source MME. This message is sent by the eNB to request the release of the UE-associated S1-logical connection over the S1 interface: with ‘Cause IE’ set to ‘Inter-RAT redirection’ to indicate the reason for triggering the UE Context Release Request procedure.

Upon receipt of the Redirection Information received in the RRC Connection Release message, the UE

leaves EUTRA-FDD old cell and start access UTRA-FDD new cell.






2.2.1 eUTRA To UTRA Redirection Procedure [cont.]

Release/ Cell RedirectionCompletionPhase

MME Keeps UE Context

MME

S1-AP UE Context Release CommandMME UE S1AP IDeNB UE S1-AP ID

Cause=Normal Release

eNB Releases UE context

S1-AP UE Context Release CompleteMME UE S1AP IDeNB UE S1-AP ID

eNB Releases associated old resources

MME releases associatedS1 resources

COMPLETION PHASE:

Upon receipt of the S1AP UE CONTEXT RELEASE REQUEST, the source MME sends a S1AP UE CONTEXT

RELEASE COMMAND message to the Source eNodeB.

The completion in the ENB ends upon receipt S1AP UE CONTEXT RELEASE COMMAND and sending by the ENB to the source MME of a S1AP UE CONTEXT RELEASE COMPLETE of a or upon guard timer expiration.






2.2.1.1 eUTRA To UTRA Measurement Reporting Setting

Parameter offsetFreqUTRA physCellIdUTRA

Object

ENBEquipment/ Enb/ RrmServices/ UeMeasurementConf/ MeasObject/ MeasObjectUTRA

ENBEquipment/ Enb/ LteCell/ UtraNeighboring/UtraFddNeighboringFreqConf/ UtraFddNeighboringCellRelation

Range & Unit Integer in dB [-15..15] step = 1

Integer [0..511] step = 1

Class/Cat C / Optimization - Tuning C / Fixed Value recommended value is 0 OD

offsetFreqUTRA: this parameter configures the IE offsetFreq included in the IE MeasObjectUTRA in the IE

MeasConfig.

offsetFreq that is used to indicate a frequency specific offset to be applied when evaluating triggering

conditions for measurement reporting. The value in dB.

physCellIdUTRA: this parameter configures the IE physCellId that is used to indicate the physical

layer identity of the cell, i.e. the primary scrambling code, as defined in TS 25.331. The IE physCellId is

included in the IE MeasObjectUTRA in the IE MeasConfig. The IE physCellId is included in the IE MeasResults in the IE MeasResultUTRA.






2.2.1.2 UTRA Event B2 Configuration

RRC Measurement Conf /0measQuantityUtraFDD

eNBEquipement

eNB

LTECell UtraFddNeighboringCellRelation/0-63- CID/Lac/PhyCellIdUtran/rac- utraFddNeighboringFreqConfid

UtraFddNeighboring

UtraFddNeighboringFreqConf/0-15- PriorityOfFreq- bandUtraFDDsupported by the UE- priorityOfBandUtraFddexhibits the highest priority

RRC Measurement Conf /0measQuantityUtraFDD

MeasObjectUtraoFFsetFreqUTRA

ReportConfigUTRA- threshold1EutraRsrp- threshold2UtraRscp- triggerTypeInterRAT- Hysteresis- timeToTrigger

MeasurementIdentityConf/0-31

MeasObject/0-31

MeasConfig/0-31

ReportConfigeUTRA- TriggerQuantity

RrmServices

UeMeasurementConf

measQuantityUtraFddMeasurementIdentityConfMO: each instance defines a RRC measurement identity and

refers to an instance of MeasObjectMO and an instance of ReportConfigMO.

The parameter measurementPurposeidentifies the goal of the measurement.To identify that an instance of

MeasurementIdentityConfis relating to a mobility case to UTRA-FDD, the parameter

measurementPurposeshall be set to Blind-Redirection-To-3GPP-RAT-Or-PS-Handover-To-UTRA-FDDor Meas-

Redirection-To-UTRA-FDD

FDDReportConfigMO: each instance defines the characteristics of the measurements.A specific instance shall be valorized in MIM to configure the RRC measurement dedicated to the event B2for UTRA-FDD.When the MG are required or not required, the operator shall provide at least one instance dedicated to B2 for UTRA-FDD.ReportConfigMO






RRC Measurement Configuration

Parameter measQuantityUtraFdd filterCoefficientOfQuantityConfigUtra

ObjectENBEquipment/ Enb/ RrmServices/ UeMeasurementConf/ RrcMeasurementConf

Range & Unit

Enumerate [cpichRSCP, cpichEcN0]

Enumerate [fc0, fc1, fc2, fc3, fc4, fc5, fc6, fc7, fc8, fc9, fc11, fc13, fc15, fc17, fc19]

Class/Cat C--New-set-ups / Fixed C--New-set-ups / Optimization -Tuning

Value cpichRSCP Ofc4

measQuantityUtraFdd: measQuantityUtraFdd = ENUMERATED {cpichRSCP, cpichEcN0} to configure the IE

measQuantityUTRA-FDD of the QuantityConfigUTRA SEQUENCE {measQuantityUTRA-FDD, measQuantityUTRA-TDD, filterCoefficient}

filterCoefficientOfQuantityConfigUtra: filterCoefficientOfQuantityConfigUtra DEFAULT fc4 to configure the

IE filterCoefficient of the QuantityConfigUTRA SEQUENCE {measQuantityUTRA-FDD, measQuantityUTRA-TDD,

filterCoefficient}. The parameter is optional and is present only when inter-RAT mobility to UTRA is

supported.






Report Configuration

Parameter maxReportCells hysteresis timeToTrigger reportInterval reportAmount

Object ENBEquipment/ Enb/ RrmServices/ UeMeasurementConf/ ReportConfig/ ReportConfigUTRA

Range & Unit integer [1..8] step = 1

Float in dB [0.0..15.0] step = 0.5

Enumerate in ms [ms0, ms40, ms64,ms80, ms100,ms128, ms160,ms256, ms320,ms480, ms512,ms640, ms1024,ms1280,ms2560, ms5120]

Enumerate in ms or min [ms120, ms240, ms480,ms640,ms1024,ms2048,ms5120,ms10240,min1,min6,min12,min30,min60

Enumerate [r1, r2, r4,r8, r16, r32,r64, infinity]


Value Recommendedvalue is 1

performance test team recommendedvalue is 4.0

recommendedvalue is ms100

recommendedvalue: ms240

Recommededvalue is r8

maxReportCells: This parameter configures the IE maxReportCells included in the IE ReportConfigInterRATin the MeasConfig IE This parameter defines the maximum number of cells to be reported in a measurement report

hysteresis: This parameter configures the IE hysteresis included in the IE ReportConfigInterRAT in the

MeasConfig IE: This parameter defines the hysteresis used by the UE to trigger an intra-frequency event-

triggered measurement report.

Trigger :This parameter configures the IE TimeToTrigger included in the IE ReportConfigInterRAT in the

MeasConfig IE

reportInterval: This parameter configures the IE reportInterval included in the IE ReportConfigInterRAT in

the MeasConfig IE: The ReportInterval indicates the interval between periodical reports. The ReportInterval is applicable if the UE performs periodical reporting (i.e. when reportAmount exceeds 1), for triggerType

‘event’ as well as for triggerType ‘periodical’.

reportAmount: This parameter configures the IE reportAmount included in the IE ReportConfigInterRAT in

the MeasConfig IE :this parameter configures the number of periodical reports the UE has to transmit after the event was triggered. reportInterval is used in the process: Measurement reporting;

1> if the numberOfReportsSent as defined within the VarMeasReportList for this measId is less than the reportAmount as defined within the corresponding reportConfig for this measId:

2> start the periodical reporting timer with the value of reportInterval as defined within the corresponding reportConfig for this measId;[R08]






2.2.2 Thresholds For Inter-Rat Mobility Foe Event B2

For redirection, the UE shall: For UTRA and CDMA2000, only trigger the event for cells included in the corresponding

measurement object.Consider the entering condition for this event to be satisfied when both condition B2-1

and condition B2-2, as specified below, are fulfilled. Consider the leaving condition for this event to be satisfied when condition B2-3 or

condition B2-4.

Inequality B2-1 (Entering condition 1): Ms + Hys < Thresh1

Inequality B2-2 (Entering condition 2) Mn + Ofn –Hys > Thres 2

Inequality B2-3 (Leaving condition 1) Ms – Hys > Thres1

Inequality B2-4 (Leaving condition 2) Mn + Ofn + Hys < Thresh2

The variables in the formula are defined as follows:

Ms is the measurement result of the serving cell, not taking into account any offsets. is expressed in dBm in case of RSRP, or in dB in case of RSRQ. i.e ReportConfigEUTRA::triggerQuantity setting.

Mn is the measurement result of the inter-RAT neighbor cell, not taking into account any offsets. is

expressed in dBm or dB, depending on the measurement quantity of the inter-RAT neighbor cell. i.e

RrcMeasurementConf::measQuantityUtraFdd setting.

Ofn is the frequency specific offset of the frequency of the inter-RAT neighbor cell (i.e. offsetFreq as

defined within the measObject corresponding to the frequency of the inter-RAT neighbor cell). i.e

MeasObjectUTRA::offsetFreqUTRA

Hys is the hysteresis parameter for this event (i.e. hysteresis as defined within reportConfigInterRAT for

this event). i.e ReportConfigUTRA::hysteresis

Thresh1 is the threshold parameter for this event (i.e. b2-Threshold1 as defined within

reportConfigInterRAT for this event).i.e ReportConfigUTRA::thresholdEutraRsrpB2 if you had chosen to use

RSRP

ReportConfigUTRA::thresholdEutraRsrqB2 if you had chosen to use RSRQ

Thresh2 is the threshold parameter for this event (i.e. b2-Threshold2 as defined within

reportConfigInterRAT for this event). i.e ReportConfigUTRA::thresholdUtraRscp or ReportConfigUTRA::thresholdUtraEcN0 , depending of measQuantityUtraFdd

Ofn, Hys are expressed in dB.

Thresh1 is expressed in the same unit as Ms.

Thresh2 is expressed in the same unit as Mn.





2.2.2 Thresholds For Inter-Rat Mobility Foe Event B2

2.2.2.1 Thresholds & Measurement Parameters For B2

Parameter triggerTypeInterRAT

thresholdEutraRsrpB2

threshold1EutraRsrq

thresholdUtraEcN0

thresholdUtraRscp

Object ENBEquipment/ Enb/ RrmServices/ UeMeasurementConf/ReportConfig/ ReportConfigUTRA

Range & Unit

Enumerate [eventB1, eventB2 ]

Integer in dBm[-140..-43] step = 1

Float in dB [-20.0..-3.0] step = 0.5

Float in dB [-24.5..0.0] Step = 0.5

Integer in dBm[-120..-24] Step = 1


Value For LTE to UTRA mobilityprocedureincludingmeasurement-basedredirection and PS handover, eventB2 shouldbe used. For CS fallback to UTRA, eventB1 should be used.

4G OPENED recommendedvalue: -100dBm

recommendedvalue is -14.5 or -24.5

recommendedvalue is -97 or -114

triggerTypeInterRAT: : This parameter configures the IE triggerType included in the IE

ReportConfigInterRAT in the IE MeasConfig

thresholdEutraRsrpB2: : This parameter configures the IE Threshold EUTRA RSRP included in the IE

ReportConfigInterRAT in the MeasConfig IE. This IE should be present if the parameter triggerTypeInterRAT is set to event B2. Otherwise it should be absent.

thresholdEutraRsrqB2: This parameter configures the IE Threshold EUTRA RSRQ included in the IE

ReportConfigInterRAT in the MeasConfig IE. This IE should be present if the parameter triggerTypeInterRAT is set to event B2. Otherwise it should be absent.

thresholdUtraEcN0: This parameter configures the IE utra- EcN0 included in the IE

ReportConfigInterRAT in the MeasConfig IE. This IE can be present only if the parameter triggerTypeInterRATis set to eventB2 and the measurement report is for UTRA-FDD. Otherwise it should be absent.





3 RRC Connected Mobility: PS Handover






3.1 PS Handover to UTRAN

LA3.0 introduced the UE measurement-based Packet Switched (PS) handover procedure

to move UE from LTE to UTRAN.

eNB will trigger the PS handover when UE is leaving LTE coverage area and moving into

UTRAN coverage area, and the UE measurement report indicates that the LTE radio

condition becomes worse than the configuration parameter

thresholdEutraRsrpB2 or thresholdEutraRsrqB2

and the UTRA radio condition becomes better than the configuration parameter

thresholdUtraEcN0 or thresholdUtraRscp .

PS

Parameter isPsHoToUtraAllowed


Range & Unit Boolean [True, False] Class/Cat C– Immediate-propagation / Fixed

Value The parameter can be set to true only if ActivationService::isMobilityToUtranAllowed is set to ‘True’.

Comparing with redirection mechanism,PS handover from LTE to UTRAN has the advantage of allocating

the resources in UTRAN prior to the execution of PS handover. Besides, PS handover has the capability of data forwarding from source LTE to target UTRAN. It thus reduces the service interruption time and ensuresbetter performance to packet loss sensitive services, such as VoIP.

When eNB receives a UE event B2 or event B1 (for CS fallback) measurement report with measurement

purpose set to ‘Mobility-Inter-RAT-to-UTRA’, and with valid reported cells (reported PhysCellIdUTRA-FDD

Corresponds to UtraFddNeighboringCellRelation::physCellIdUTRA of an instance of UTRA neighbor), LTE to

UTRAN PS handover procedure will be triggered if all of the following conditions are satisfied:

PS handover to UTRAN is allowed for the eNB (ActivationService::isPsHoToUtraAllowed is set to ‘True’)

UE is capable to support PS handover to UTRAN

A RNC controlling one or more reported candidate cells (Controlling RNC is pointed to by

UtraFddNeighboringCellRelation::rncAccessId) is capable to support PS handover

(RncAccess::psHandoverUtraEnabled is set to ‘True’)





3.1 PS Handover to UTRAN

3.1.1 PS HO Related Parameters

Parameter rncAccessId psHandoverUtraEnabled

Object

ENBEquipment/ Enb/ LteCell/ UtraNeighboring/ UtraFddNeighboringFreqConf/ UtraFddNeighboringCellRelation

ENBEquipment/ Enb/ UtranAccessGroup/ RncAccess

Range & Unit ServiceLink Boolean [True, False]

Class/Cat C– New-setups / Fixed

Value This parameter should point to the RncAccess instance thatcontrols the UTRA neighbor cellassociated with the UtraFddNeighborCellRelationinstance.

This parameter should be set to ‘True’ if the neighbor RNC iscapable to support the PS handover from LTE to UTRA FDD/TDD.

If either PS handover to UTRAN is not allowed for the eNB (ActivationService::isPsHoToUtraAllowed is set to ‘False’), or UE is incapable to support PS handover to UTRAN, or there is no RNC controlling the reported candidate cells capable to support PS handover, a measurement-based redirection procedured introduced by FRS-76498 will be triggered.

The LTE to UTRAN PS handover procedure has the following two phases:

1) Handover Preparation Phase

2) Handover Execution Phase






3.2 PS HO Procedure In eNB: Preparation Phase


MME

Triggers:-an A2 measurement report is received-a B2 measurement report is received-a B1 measurement report is received

HO RequiredMME-UE-S1AP-IDeNB-UE IDHandoverType=ltetoutranCause=handover-desirable-for-radio-ReasonTargetIDDirect-Forwarding-Path-AvailabilitySource-ToTarget-TransparentContainer

HO Command MME-UE-S1AP-IDeNB-UE-S1AP-

IDHandoverType=ltetoutranNASSecurityParametersfromE-UTRANE-

RABSubjecttoDataForwardingListE-RABtoReleaseListHOCmdTarget-ToSource-

TransparentContainer

TS1RELOCprep

If PS handover is to be performed, eNB will select the best UTRA cell reported by the UE that are allowed

to be handover to as the PS handover target cell. The selected target cell should not in the

HandoverRestrictionList for the UE (received from MME) and the controlling RNC of the cell should have

RncAccess::psHandoverUtraEnabled set to ‘True’.

eNB will send a Handover Required message to the MME and start timer TS1relocprep with duration

PsHoToUtraTimersConf::tS1RelocPrepForPsHandoverToUtra (the PsHoToUtraTimersConf instance is

pointed to by the RncAccess::psHoToUrtaTimerConfId associated with the selected

UtraFddNeighboringCellRelation).






3.3 PS HO Procedure In eNB: Handover Execution

Release Completion

Handover Execution

MME

TS1RELOCoverall

HANDOVER COMMANDMME-UE-S1AP-IDeNB-UE-S1AP-ID

HandoverType=ltetoutranNASSecurityParametersfromE-UTRAN

E-RABSubjecttoDataForwardingListE-RABtoReleaseListHOCmd

Target-ToSource-TransparentContainer

RRC MOBILITY FROM EUTRA COMMANDcs-FallbackIndicator = false

purpose = handovertargetRAT-Type = utra

targetRAT-MessageContainernas-SecurityParamFromEUTR

UE CONTEXT RELEASE COMMANDMME-UE-S1AP-IDENB-UE-S1AP-ID

Cause=normal-release

UE CONTEXT RELEASE COMPLETEMME-UE-S1AP-IDENB-UE-S1AP-ID

MME releases Associated S1 resources

eNB releases the UE Context and associated

resources

The UE synchronizes to the Indicated UTRAN cell and

completes the HO

If UE Context Release Command is received from MME, PS handover is successful. eNB will send a UE

Context Release Complete to MME. eNB will stop timer TS1relocoverall and release UE context and associated resources.

If timer TS1relocoverall expires, eNB considers the UE to have lost radio coverage and will trigger the

release of all UE associated resources by sending an UE Context Release Request to MME and release all UE

associated resources in eNB.






3.4 PS HO Preparation Phase Related Parameters

Parameter psHoToUtraTimerConfId

rncId cId tS1RelocPrepForPsHandoverToUtra

Object

ENBEquipment/ Enb/ UtranAccessGroup/ RncAccess

ENBEquipment/ Enb/ LteCell/ UtraNeighboring/ UtraFddNeighboringFreqConf/ UtraFddNeighboringCellRelation

ENBEquipment/ Enb/ S1AccessGroup/ S1Timers/ PsHoToUtraFddTimersConf

Range & Unit ServiceLink Integer [0 - 4095] step = 1

Integer [0..65536] step 1

Integer in ms [1 – 10000] step = 1

Class/Cat C – New-Setups / Fixed C – New Setups / Optimization –Tunin

Value should point to the psHOToUtraTimerConf instance withtimer values to beused for the PS handover to the RNC.

O.D recommendedvalue: 4000

If reservation of resources in the target UTRAN cell is successfully completed, MME will send a Handover

Command message to eNB. eNB will then stops the timer TS1relocprep and enter the handover execution

phase.

If timer TS1relocprep expired, or eNB receives a S1 handover Preparation Failure message, handover

preparation fails. In this case, if PS handover preparation was due to a CS fallback request, eNB will trigger a measurement-based redirection to UTRAN. Otherwise, the UE measurement report will be ignored.

Some of the parameters included in the Handover Required message are populated from the configurable

parameters:

• Target RNC-ID

• Direct Forwarding Path Availability (RncAccess::directFwdPathAvailability)

• Source to Target Transparent Container includes: Cell-ID (UtraFddNeighboringCellRelation::cId)





4 CS FALLBACK





4 CS FALLBACK

4.1 CSFB Function

Circuit switched (CS) fallback is a function that moves UE from LTE network to a different RAT that supports CS voice service when a CS voice call needs to be set up.

In LA3.0, two CS fallback features are supported in eNB:CS Fallback to GERAN for Voice Calls. CS Fallback to UTRA for Voice Calls. Enhanced RRC Releases redirection for CSFB to UTRAN.

‘CS Voice only’‘CS Voice preferred and IMS PS Voice as secondary’‘IMS PS Voice preferred and CS Voice as secondary’‘IMS PS Voice only’.

CS Network

PS Network

GERAN

eUTRAN

UTRAN

CS Services

PS Services

Based on the configuration setting of the UE, it may request CS fallback when a voice call is to be set up and one of the following conditions is true:

UE is set to ‘CS Voice preferred’ or ‘CS Voice only’ and needs to make a voice call or an emergency voice call.

set to ‘IMS PS Voice preferred’, ‘CS Voice preferred’ or ‘CS Voice only’ and a mobile terminated CS voice call is to be set up.

UE is set to ‘IMS PS Voice preferred’ and needs to make an emergency voice call, but the LTE network does not support VoIP emergency calls.

If CS fallback is not possible (either UE or network does not support CS fallback, or UE fails to attach to LTE

network) when UE needs to set up a CS voice call, it will search for a different RAT that supports CS voice callwithout the help from the LTE network.





4.1 CSFB Function

4.1.1 CS Fallback Procedure in eNB

CS fallback starts when MME receives an Extended Service Request from the UE requesting CS fallback.

MME will then send to eNB with CSFallbackIndicator an Initial Context Setup Request at call setup or a UE Context Modification Request during a data call.

This will trigger the CS fallback procedure in eNB, if at least one of the CS fallback features is activated.

Parameter isCsFallbackToUtraFddAllowed isCsFallbackToGeranAllowed

Object Enb/ ActivationService

Range & Unit Boolean [True, False] Class/Cat C – New-set-ups / Fixed

Value The parameter can be set to trueonly ifActivationService::isMobilityToUtraAllowed is set to ‘True’.

The parameter can be set to trueonly ifActivationService::isMobilityToGeranAllowed is set to ‘True’.





4 CS FALLBACK

4.2 CSFB Triggered By An Idle UE

MME

The UE has previously performed a combined Attach, indicating to the MME that it is CS Fallback capable

Only for a m

obile term

inated Call

RRC Connection setup

Paging

establishmentCause = mo-Access or mt-Access

RRC connection request

DedicatedInfoNAS = Extended Service Request> Service Type> CSFB Response

RRC connection setup Complete

Initial UE Message

PagingCNDomain = cs

CNDomain = cs

Initial Context Setup request

CSFallbackIndicator

NAS-PDU = Extended Service RequestRRC-Establishment-Cause

The Service Type is one of:-mobile originating CS fallback or 1xCS fallback-mobile terminating CS fallback or 1xCS fallback-mobile originating CS fallback emergency callor 1xCS fallback emergency call





4 CS FALLBACK

4.3 CSFB Triggered By a Connected UE

MME

The UE has previously performed a combined Attach, indicating to the MME that it is CS Fallback capableThe UE is RRC_Connected at the time that CS Fallback is needed O

nly for a mobile

terminated Call

Downlink NAS Transport

DedicatedInfoNAS = Extended Service Request> Service Type> CSFB Response

DL Information TransferNAS-PDU = CS Service Notification

UE Context modification requestCSFallbackIndicator

NAS-PDU = Extended Service Request

The Service Type is one of:-mobile originating CS fallback or 1xCS fallback-mobile terminating CS fallback or 1xCS fallback-mobile originating CS fallback emergency callor 1xCS fallback emergency call

NAS-PDU = CS Service Notification

UL Information Transfer

UPlink NAS Transport

The decision on which candidate RAT/carrier to perform CS fallback is made by eMCTA framework based on the priority of each RAT/carrier neighbor configured by the operator for csFallback or mergencyCallCsFallback purpose.

A set of filters including UE capability filter, network capability filter, etc and HORestrictionList for the UE (received from MME) are used to remove the RAT/carriers that are not supported by the UE or network for CS fallback from the prioritized RAT/carrier neighbor list. The highest priority RAT/carrier after the filteringis selected as the target RAT/carrier for CS fallback.

If the selected target carrier is a UTRA carrier:

eNB will configure the UE to perform event B1 or event B2 measurement to the UTRA carrier if UE supports it. eNB will trigger a PS handover to UTRA after UE measurement report is received for CS fallback to UTRA. Refer to CS Fallback Triggered by PS handover.

Otherwise, eNB will perform the LTE to UTRA blind redirection procedure to move the UE to UTRA for CS

fallback. CS Fallback Triggered by Redirection.

Whenever redirection from LTE to UTRA is performed for CS fallback except in the case when redirection istriggered by UE entering ‘Below-Serving-Floor’ area, target cell System Information will be provided in the RRCConnectionRelease message for redirection assistance if following conditions are Met.





4 CS FALLBACK

4.4 CSFB Triggered by PS Handover

MME

CSFallbackIndicator

Initial Setup Request/ UE Context modification Request

Security Mode Command

Initial Context Setup Response or UE Context Modification Response


Security Mode Complet



UE Capability Enquiry

UE Capability Information

The eNB configures B1 measurement to the UE for UTRAN carrier and removes any measurement that could complete for gaps pr time.The eNB may alsoforce the UE into DRX to speed up measurmemnt

MeasConfig

RAT-Type= UTRA

RadioResourceconfigDedicated


1

2

(1) Security must be activated and SRB2 and at least one DRB must be set up before triggering the HO.

It will already have been for a UE context modification, but not for an initial context setup.

(2) UTRA capabilities will have to be requested in the case of CS FB triggered at initial context setup.





4 CS FALLBACK

4.4 CSFB Triggered by PS Handover [cont.]

MME

CS FB Indicator:: TruePurpose: Handover

Target RAT-Type= UTRATargetRAT message containerNas securityParamFromEUTRA

HandoverType= ltetoutranCause:CS-FB TriggeredSource to Target= Transparent container=Source RNC to Target RNC Transparent Container

RNC Container=Inter RAT Handover info with inter RAT capabilitiesUE History Information

Measurement Report

HO Required

HO Command

HandoverType= ltetoutranNASSecurityParmetersfrom EUTRAN

Source to Target= Transparent container=Source RNC to Target RNC Transparent

ContainerMobility From EUtra command

UE context Release Command

UE context Release Complete





4 CS FALLBACK

4.5 CSFB UE Measurement Configuration

For CS fallback to UTRA or GERAN, eNB will configure UE to perform event B1 The entering condition (for UE to start measurement reporting) and the leaving

condition (for UE to stop the measurement reporting) are as below:

>> Event B1 entering condition:Mn + offsetFreq – hysteresis > threshold

>> Event B1 leaving condition:Mn + offsetFreq + hysteresis < threshold

RRC Configuration (B1 Event Measurement)

Supports B1 Event

Meas

Doesn’tSupport B1 Event

Meas

RRC Configuration (B2 Event Measurement)

UE triggers measurement reporting when the Radio condition of the inter-RAT neighbor cell becomes better than a threshold value

Event B2 is used only if event B1 is not supported by the UE.

When CS fallback to UTRA is activated in eNB, operator should configure in each cell one or multiple instances of MeasurementIdentityConf with measurementPurpose set to ‘Mobility-Inter-RAT-to-UTRA’ and measObjectLink and reportConfigLink pointing to the properly configured MeasObjectUTRA instance (with valid carrierFreq as configured in a UtraFddNeighboringFreqConf instance) and ReportConfigUTRA instance (with triggerTypeInterRAT set to ‘eventB1’). Operator should also configure one or multiple instances of RrcMeasurementConf with measurementIdentityConfIdList including one or multiple instances of MeasurementIdentityConf with measurementpurpose set to ‘Mobility-Inter-RAT-to-UTRA’. Similarly, when CS fallback to GERAN is activated in eNB, operator should configure in each cell one or multiple instances of MeasurementIdentityConf with measurementPurpose set to ‘Mobility-Inter-RAT-to-GERAN’ and measObjectLink and reportConfigLink pointing to the properly configured MeasObjectGERANinstance (with valid geranARFCNList as configured in a GeranNeighboringFreqsConf instance) and the ReportConfigGERAN instance (with triggerTypeInterRAT set to ‘eventB1’). Operator should also configure one or multiple instances of RrcMeasurementConf with measurementIdentityConfIdList including one or multiple instances of MeasurementIdentityConf with measurementpurpose set to ‘Mobility-Inter-RAT-to-GERAN’.

If target carrier is in GERAN, ReportConfigGERAN::hysteresis is used.• threshold is the threshold parameter for event B1.o If target carrier is in UTRAN,ReportConfigUTRA::thresholdUtraRscp or ReportConfigUTRA::thresholdUtraEcN0 is used depending onRrcMeasurementConf::measQuantityUtraFdd is set to cpichRSCP or cpichEcN0.o If target carrier is in GERAN,ReportConfigGERAN::thresholdGeran is used.





5 Evolved Multi-Carrier Traffic Allocation (e-MTCA)






5.1 e-MTCA Overview

eMTCA, intoduced in LA3.0 is a proprietary ALU mobility management framework in the eNB used for allocating the traffic efficiently for LTE sessions across multiple RAT and multiple LTE RF carriers based on enhanced triggers.

eMTCA supports the mobility management of inter-frequency LTE neighboring carriers, inter RAT GERAN neighboring carriers, inter-RAT UTRAN neighboring carriers, and inter RAT CDMA 2000 HRPD neighboring carriers.

In LA3.0, eMTCA can be invoked either by serving radio monitoring via RRC Measurement, or CSFB via CSFB indicator from the MME.

eMTCA is invoked only in the RRC-connected mode

eMTCA feature introduces a common mobility framework, E-MCTA, which is a proprietary ALU solution to

allocate the traffic efficiently for LTE sessions across multiple RAT and multiple LTE RF carriers during

handover and call admission control based on triggers and filters for the Mobility Domain, Services Domain,

and Capacity Domain.

When E-MCTA is triggered, it takes as an input neighboring RAT/carriers of the serving LTE cell, it applies

filters, and it provides as an output a sorted list of candidate RAT/carriers for RRC Measurements. This

functionality is part 1 of e-MTCA feature.

The RRC measurement configuration function relies on part 1 of the E-MCTA process since the list of

Measurement Objects towards which the UE performs measurements is the candidate RAT/carrier list

output of the E-MCTA process plus the mandatory intra-frequency measurements like A3 for intra-frequency

mobility or A2-floor for blind redirections.






5.1 e-MTCA Overview [cont.]

(1)RRC

Measurement process

(3) Mobility

procedures

Redirection

Inter-Frequency HOPS Handover

Cell Change Order

RRC Measurement reports(triggers radio mobility)

S1AP Fallback Indicator IE(triggers CS Fallback)

Inter-Frequ/ Intra-FrequMeasurement config

Measurement Based Mobility

Blind mobility

Blind candidate RAT/ carriersstored

Measured candidate RAT/ Carriers sorted (2)

eMTCAFramework

UE Capabilities

Configured RAT/ Carrier neighbors:Lte/UtraFdd/ Geran / Hrpd Neighboring







INPUT: Un-SortedNeighbor RAT/Carrier

List

OUTPUT: CandidateNeighbor RAT/Carrier

sorted List

RAT/Carriers Filtered Out

Serving Radio Monitoring

Load

ResourceShortage

Traffic Segmentation

CS Fallback

UE Capability

SubscriberProfile

Service Segmentation

NetworkCapability

Mobility PathInformation

Fair Loading Policy

E-MCTA Triggers

E-MCTA Filters

Services

Mobility

Capacity

E-MCTA PROCESS PART 1

eMTCA feature introduces a common mobility framework, E-MCTA, which is a proprietary ALU solution to

allocate the traffic efficiently for LTE sessions across multiple RAT and multiple LTE RF carriers during

handover and call admission control based on triggers and filters for the Mobility Domain, Services Domain,

and Capacity Domain.

When E-MCTA is triggered, it takes as an input neighboring RAT/carriers of the serving LTE cell, it applies

filters, and it provides as an output a sorted list of candidate RAT/carriers for RRC Measurements. This

functionality is part 1 of e-MTCA feature.

The RRC measurement configuration function relies on part 1 of the E-MCTA process since the list of

Measurement Objects towards which the UE performs measurements is the candidate RAT/carrier list

output of the E-MCTA process plus the mandatory intra-frequency measurements like A3 for intra-frequency

mobility or A2-floor for blind redirections.







Monitored RRC MeasurementsSorted List

E-MCTA: CandidateNeighbor RAT/Carrier

sorted List

E-MCTA PROCESS PART 2

UTRANCarrier-1

UTRANCarrier-3

Measurement listtruncated, lowestpriority measurementsmay be removed.

Highest priority measurements(intrafrequency) appendedto top of list by RRCMeasurement function.

The final list of Measurement Objects may be truncated to limit the number of measurement needing a

Measurement Gap and to limit the overall number of measurements to be configured for UE performance

considerations. This is part 2 of e-MTCA feature.






5.2 e-MCTA Triggers & Filter

Mobility Domain Triggers

Coverage Alarm

RRC Measurement Report:EventA2 and Measurement purpose =‘Entering-Coverage-Alarm’

RRC Measurement Report:EventA2 and Measurement purpose =‘Entering-Coverage-Alarm’

Below Serving Floor

RRC Measurement Report:EventA2 and Measurement purpose = ‘Below-Serving-Floor’

RRC Measurement Report:EventA2 and Measurement purpose = ‘Below-Serving-Floor’

Service Domain Triggers

CS Fall Back (CSFB)

S1AP Initial Context Setup Request/ S1AP ContextModification Request:S1AP CS Fallback Indicator IE

S1AP Initial Context Setup Request/ S1AP ContextModification Request:S1AP CS Fallback Indicator IE

UE Capability Filter

Network Capability

Filter

Mobility Path Information

Filter

Mobility Path Information

Filter

E-MCTA process limits the number of filters to compute the E-MCTA output.

E-MCTA process limits the number of E-MCTA triggers

- Coverage Alarm: Triggers RRC measurements for neighboring carriers to be filtered and sorted

according to their configured priority and to possibly truncate the measurement list per operator

configuration parameter settings. To avoid systematic truncation of the same carrier(s), measurements of

carriers having the same priority are sorted randomly. RRC Measurements with eventB2 report configuration

are configured for inter-RAT or inter-frequency mobility.

- Below Serving Floor: Triggers neighboring carriers to be filtered and sorted according to their configured

priority and only one single carrier with the highest priority from the sorted list is selected as the target

RAT carrier. If there is more than one carrier with highest priority, then one of them is randomly chosen

to avoid always selecting the same carrier. RRC Measurements are not configured for blind redirection.

- CS Fallback (CSFB): E-MCTA triggered by CSFB is the reception of S1AP CS Fallback Indicator IE in

message S1AP INITIAL CONTEXT SETUP REQUEST or S1AP CONTEXT MODIFICATION REQUEST. Neighboring RAT

carriers are filtered and sorted according to their configured priority and only one single carrier

with the highest priority from the sorted list is selected as the target RAT carrier.

If there is more than one carrier with highest priority, then one of them is randomly chosen to avoid always

selecting the same carrier. Either a single B1 or B2 RRC Measurement may be configured for CSFB. If CSFB

via a handover procedure is not possible, then blind redirection is performed and thus no RRC Measurement

is configured for the CSFB.





5.2 e-MCTA Triggers & Filter

5.2.1 Coverage Alarm Entry Measurement Configuration

ReportConfig trigger Type

Measurement Purpose Trigger Quantity and thresholds

triggerTypeEUTRA =eventA1

Leaving_Coverage_Alarm If If rsrp, then A1_CA_threshold is value of• ReportConfigEUTRA::thresholdEutraRsrp

triggerTypeInterRAT= eventB2

Invoke eMCTA algorithm for carrier selection. If UTRAcarriers selected:Mobility-Inter-RAT-to-UTRA

If rsrp, then B2_threshold1 is • ReportConfigUTRA::thresholdEutraRsrpB2---------------------------------------------------If EcN0, then B2_threshold2 is• ReportConfigUTRA::thresholdUtraEcN0

triggerTypeInterRAT=eventB2

Invoke eMCTA algorithm for carrier selection. If GERAN carriers selected:Mobility-Inter-RAT-to-GERAN

If rsrp, then B2_threshold1 is• ReportConfigGERAN::thresholdEutraRsrpB2----------------------------------------------------B2_threshold2 is• ReportConfigGERAN::thresholdGeran

measurementPurpose = Mobility-Inter-RAT-to-UTRA (eventB2) should be configured if the network will

have dual-mode UEs capable of IRAT measurements to UTRANs.

measurementPurpose = Mobility-Inter-RAT-to-GERAN (eventB2) should be configured if the network will

have dual-mode UEs capable of IRAT measurements to GERANs.






5.3 Input/Output: Unsorted RAT/Carrier List

Input Unsorted RAT/Carrier List

The e-MCTA process considers a full serving neighbor cell Configuration consisting of multiple RATs, bands and carriers.

This is the main input called the ‘Neighbor RAT/Carrier List’.

The e-MCTA process can only use the RAT/carriers configured in the eNodeBdata configuration.

e-MCTA will process measurement based allocations only for GERAN and UTRA-FDD inter-RAT target carriers to support the following: CS Fallback, EUTRA-to-GERAN NACC and Measurement Gap.

Output: Unsorted RAT/Carrier List

The output of the E-MCTA process is a sorted carrier list according to carrier priorities, in order of decreasing priorities (7 is the highest priority, 0 is the lowest).

The eNodeB relies on SAM/WPS to enforce rules such as carriers of different RATs must have different priorities.

If some carriers of the same RAT have the same priority, eMCTA will sortthem in random order in the carrier list.

Complete LA3.0 E-MCTA functionality is expected to be delivered in a future LA3.0 drop, which will also

include allocations for measurement based CDMA2000-HRPD and LTE inter-frequency target carriers.

INPUT: UN-SORTED RAT/CARRIER LIST

The LA3.0 E-MCTA process considers a full serving neighbor cell configuration consisting of multiple RATs,

bands and carriers. This is the main input called the ‘Neighbor RAT/Carrier List’. The E-MCTA process can only

use the RAT/carriers configured in the eNodeB data configuration

UTPUT: SORTED RAT/CARRIER LIST The output of the E-MCTA process is a sorted carrier list according to carrier priorities, in order of decreasing

priorities (7 is the highest priority, 0 is the lowest). The eNodeB relies on SAM/WPS to enforce rules such as

carriers of different RATs must have different priorities. However, carriers of the same RAT may have the

same or different priority. If some carriers of the same RAT have the same priority, eMCTA will sort them in

random order in the carrier list.






5.4 e-MCTA Filtering Algorithm

FGI bit #22&#8 is set

UTRAN Band Supported

FGI bit #23&#10 is set

GERAN Band Supported

GERAN CarrierList

UTRAN CarrierList

Un-sorted candidateRAT Carrier List

Exclude all GERAN carriers for mobility

Exclude all GERAN carriers for RRC Measurement

Exclude all GERAN carriers of this band

Exclude all UTRAN carriers for mobility

Exclude all UTRAN carriers for RRC Measurement

Exclude all UTRAN carriers of this band

Combine

No

Yes

Yes

No

Yes

Yes

yes

No

No

yes

No

No

TRIGGER: Serving Radio Coverage Alarm

Or CSFB

A

isForbiddenRAT=All or UTRAN

isForbiddenRAT=All or GERAN

1 1

2 2

33

The mobility domain is addressed by two serving radio monitoring triggers in LA3.0:

Coverage Alarm: E-MCTA triggered by coverage alarm is the reception of RRC Measurement Report with

report configuration eventA2 and measurement purpose set to ‘Entering-Coverage-Alarm’, indicating serving radio degradation is reached at which point another RAT/carrier should be monitored. This condition triggers RRC measurements for neighboring carriers to be filtered and sorted according to their configured priority and to possibly truncate the measurement list per operator configuration parameter settings. To avoid systematic truncation of the same carrier(s), measurements of carriers having the same priority are sorted randomly. RRC Measurements with eventB2 report configuration are configured for inter-RAT mobility and eventA5/eventA3 for intra-LTE inter-frequency mobility.

Below Serving Floor: E-MCTA triggered by bad radio conditions is the reception of an RRC Measurement

Report with report configuration eventA2 and measurement purpose set to ‘Below-Serving-Floor’, indicating a strong degradation of the serving radio conditions that requires a blind redirection to another RAT carrier.

This condition triggers neighboring carriers to be filtered and sorted according to their configured priority and only one single carrier with the highest priority from the sorted list is selected as the target RAT

CS Fallback (CSFB): E-MCTA triggered by CSFB is the reception of S1AP CS Fallback Indicator IE in message

S1AP INITIAL CONTEXT SETUP REQUEST or S1AP CONTEXT MODIFICATION REQUEST. Neighboring RAT carriers

are filtered and sorted according to their configured priority and only one single carrier with the highest

priority from the sorted list is selected as the target RAT carrier. If there is more than one carrier with highest priority, then one of them is randomly chosen to avoid always selecting the same carrier. Either a single B1 or B2 RRC Measurement may be configured for CSFB. If CSFB via a handover procedure is not possible, then blind redirection is performed and thus no RRC Measurement is configured for the CSFB.






5.4 e-MCTA Filtering Algorithm [cont.]

Un-sorted candidateRAT Carrier List

A

isServiceBasedTrafficSegmentation

Allowed

Sort all candidate RAT carriers according to priority set by defaultConnectedPriorityOfFreq.

Sort all candidate RAT carriers according to priority of serviceType eMctaPriority.

eMCTA Soretd RAT Carrier List

false

trueIf all RATs are excluded, IRAT

Mobility and CSFB are not possible.

If UE does not support measurements for any RAT, then blind redirection is performed (no RRC Measto be configured).

If UE supports none of the configured neighbor GERAN and UTRAN carriers, IRAT mobility and CSFB are not possible.

1

2

3






5.5 Service Table

LTE Cell

Mobility PriorityTable

UtraTddNeighboring

FreqConf

Service TypePriorityConf

0..1

0..3

HrpdNeighboring

Hrpd NeighboringPer carrier

HrpdBandclassConf

Moblity PriorityTable

1..2

0..3

LTE Cell Neighboring


LteNeighboringFreqConf


1..9

0..3

0..1

UtraNeighboring


UtraFDDNeighboring

FreqConf


0..16

0..1

GeranNeighboring

Moblity PriorityTable

GeranNeighboringFreqsConf


0..16

0..3

0..16

0..3

The Service-Table provides one priority per service-type per RAT/Carrier. The LA3.0 E-MCTA service-table is

the unique entry that makes possible the sorting of the candidate Rat/Carrier list that is used for any E-

MCTA trigger. The Service-Table is used by the Service Segmentation Policy filter. The Service-Table is a

matrix of RAT/carrier, service-type, and priority.





5.5 Service Table

5.5.1 e-MTCA Priority

Parameter eMctaPriority

Object

ENBEquipment/Enb/LteCell/LteNeighboring/ LteNeighboringFreqConf/ MobilityPriorityTable/ServiceTypePriorityConf

ENBEquipment/Enb/ LteCell/UtraNeighboring/ UtraFddNeighboringFreqConf/ MobilityPriorityTable/ServiceTypePriorityConf

ENBEquipment/Enb/ LteCell/GeranNeighboring/ GeranNeighboringFreqsConf/ MobilityPriorityTable/ServiceTypePriorityConf

ENBEquipment/Enb/LteCell/HrpdNeighboring/hrpdBandClassConf/HrpdNeighboringPerCarrier MobilityPriorityTable/ServiceTypePriorityConf

Range & Unit Enumerate [service-not-allowed-in-RAT-carrier(0), 0-lowest(1), 1(2), 2(3), 3(4), 4(5), 5(6), 6(7), 7(8)]

Class/Cat C--New-set-ups / Optimization - Selection

Value Equal priorities between RATs are not supported. Equal priorities within GERAN are supported





5.5 Service Table

5.5.2 service Type Parameter

Parameter serviceType

Object

ENBEquipment/Enb/LteCell/LteNeighboring/ LteNeighboringFreqConf/ MobilityPriorityTable/ServiceTypePriorityConf

ENBEquipment/Enb/ LteCell/UtraNeighboring/ UtraFddNeighboringFreqConf/ MobilityPriorityTable/ServiceTypePriorityConf

ENBEquipment/Enb/ LteCell/GeranNeighboring/ GeranNeighboringFreqsConf/ MobilityPriorityTable/ServiceTypePriorityConf

ENBEquipment/Enb/LteCell/HrpdNeighboring/hrpdBandClassConf/HrpdNeighboringPerCarrier MobilityPriorityTable/ServiceTypePriorityConf

Range & Unit Enumerate [voIp(0), csFallback(1), emergencyCallCsFallback(2)] Class/Cat C--New-set-ups / Optimization - Selection

ServiceTypePriorityConf::serviceType: In order to allow the different service-based allocation strategies,

the E-MCTA process relies on the notion of service-type. This is an ALU-proprietary notion that indicates the

type of application, for which the RAT/Carrier allocation is optimized.






5.6 e-MTCA Process for RRC Measurement

The following measurements are configured to monitor the serving cell for alarm conditions:

ReportConfig:EUTRA::triggerTypeEUTRA

MeasurementIdentityConf::measurementPurpose

ReportConfEUTRA:: triggerQuantity and thresholds

eventA2 Entering_Coverage_Alarm

If rsrp used, then A2_CA_threshold is value of a. ReportConfigEUTRA::thresholdEutraRsrpIf rsrq used, then A2_CA_threshold is value of 1ReportConfigEUTRA::thresholdEutraRsrq

eventA2 Below_Serving_Floor

If rsrp used, then A2_floor_threshold is b. ReportConfigEUTRA::thresholdEutraRsrpIf rsrq used, then A2_floor_threshold is c. ReportConfigEUTRA::thresholdEutraRsrq

RRC Measurements are configured in two phases at call setup. In the first phase, the high priority intra-

frequency event A3 measurement is configured for intra-LTE intra-frequency mobility.

This measurement is maintained throughout the call.

In the second phase, lower priority measurements are configured, which include those used for monitoring the serving cell for alarm condition.

As this occurs at call setup, these measurements are configured before E-MCTA is ever invoked.





6 Measurement Gap Configuration






6.1 Measurement Gaps

A Measurement Gap (MG) is a small periodic time interval during which there is no DL transmission and no UL transmission for the UE.

This feature is activated/deactivated by parameter isMeasurementGapsAllowed.

Parameter isMeasurementGapsAllowed

Object Enb/ ActivationServiceRange & Unit Boolean [True, False]

Class/Cat C – New-set-ups / Fixed Value The recommendation is to set

isMeasurementGapsAllowed to ‘true’ when the eNodeB isconfigured to activate IRAT mobility to UTRAN or GERAN, or IRAT mobility to HRPD, or inter-frequency to EUTRAN mobility

It is a complement of the inter-RAT and inter-frequency mobility features as it allows the UE to enter in

measurement periods on other RAT/LTE carriers.

This is achieved by the creation of measurement gaps.






6.1 Measurement Gaps [cont.]

There are 2 Gap pattern configurations:

The Gap pattern is configured by parameter measurementGapsPattern.

Gap Pattern

Id

Measurement Gap Length

(MGL) in ms

Measurement Gap Repetition

Period (MGRP)

0 6 ms 40 ms

1 6 ms 80 ms

Parameter measurementGapsPattern

ObjectENBEquipment/Enb/ RrmServices/ UeMeasurementConf/ RrcMeasurementConf

Range & Unit Enumerate [length6ms_period40ms(0), length6ms_period80ms(1)]

Class/Cat C – New-set-ups / Fixed Value length6ms_period40ms(0)

There are 2 Gap pattern configurations

With a Measurement Gap Repetition Period (MGRP) of 40ms

With a Measurement Gap Repetition Period (MGRP) of 80ms.

Both patterns have a Measurement Gap Length (MGL) of 6ms.





UL

DL


6.1.1 Measurement Gaps Pattern

The starting position of the Measurement Gap in a given MG period is defined by the: UE-specific Measurement Gap Offset (MGO).

MG

SRS

Tran

smis

sion

CQI/

PMI/

RI

ACK

/NA

CK

ACK

/NA

CK

MG

MG

MG

D-B

CH

MG Offset is chosen so as to minimize the collision of MGs with the other periodic Transmissions in UL & DL.

No UL/DL Transmission during MG

The UE-specific Measurement Gap Offset (MGO) is determined so that the UE performance is degraded as

little as possible by Measurement Gaps.

Note that the MGOs of the different UEs are also chosen so that their different MGs are distributed over

time so that during the MG of some UE, a sufficient number of other UEs can transmit (and receive) and the

total cell throughput performance is not degraded.

Note that the MG offset is in the set {0, 1, ..., 39} in Gap Pattern 0 and in the set {0, 1, ..., 79} in Gap

Pattern 1






6.1.2 DRX Configuration With Measurement GAP

UE_RLC_MAC_L1_ Context_Setup_RequestInformation Element ANR DRX CONFIGURATION INFO: The field Long Cycle Start Offset is removed

UE_RLC_MAC_L1_CONTEXT_SETUP_RESPONSE:Information Element ANR DRX CONFIGURATION INFO:

"Long Cycle Start Offset" is added

CALLP

1

2

The CallP will use this value for everything

that concerns DRX for this UE.

Measurement Gap, which may be activated for mobility measurements, and DRX for ANR can be activated simultaneously.

It is preferable that the Measurement Gap does not collide with the DRX command for ANR.

To avoid a collision, the value of “Long Cycle Start Offset” is calculated by the Scheduler and given to CallP

Measurement Gap, which may be activated for mobility measurements, and DRX for ANR can be activated

simultaneously. It is preferable that the Measurement Gap does not collide with the DRX command for ANR

because this will cause the DRX command to be delayed and the “DRX Off Duration” will be shorter, by up to 10 msec (on a total of 150 msec or 310 msec, depending on the LongDRXCycle value). To avoid a collision, the value of “Long Cycle Start Offset” is calculated by the Scheduler and given to CallP.

a) At UE SETUP, in message UE_RLC_MAC_L1_CONTEXT_SETUP_REQUEST, Information Element ANR DRX CONFIGURATION INFO: the field Long Cycle Start Offset is removed. The value of "Long Cycle Start Offset" is unset until UE_RLC_MAC_L1_CONTEXT_SETUP_RESPONSE is received.

b) in message UE_RLC_MAC_L1_CONTEXT_SETUP_RESPONSE: the field Long Cycle Start Offset is added: the CallP will use this value for everything that concerns DRX for this UE.











End of ModuleMobility Management

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