ZGO-03!02!005 Dynamic Half Rate Allocation FG 20101030

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ZGO-03-02-005 Dynamic Half Rate Allocation

Feature Guide


ZTE Confidential Proprietary © 2010 ZTE CORPORATION. All rights reserved. I


Version Date Author Approved By Remarks

V1.00 2010-10-30 Not open to the Third Party

© 2010 ZTE Corporation. All rights reserved.

ZTE CONFIDENTIAL: This document contains proprietary information of ZTE and is not to be disclosed or used without the prior written permission of ZTE.

Due to update and improvement of ZTE products and technologies, information in this document is subjected to change without notice.


ZTE Confidential Proprietary © 2010 ZTE CORPORATION. All rights reserved. II

TABLE OF CONTENTS

1 Feature Attribute ............................................................................................. 1

2 Overview ......................................................................................................... 1 2.1 Feature Introduction .......................................................................................... 1 2.2 Correlation with Other Features ........................................................................ 2

3 Technical Description .................................................................................... 2

4 Parameters and Configurations ..................................................................... 4 4.1 Parameter List .................................................................................................. 4 4.2 Parameter Configuration ................................................................................... 6

5 Related Counters and Alarms ...................................................................... 11 5.1 Related Counters ............................................................................................ 11 5.2 Related Alarms ............................................................................................... 21

6 Engineering Guide ........................................................................................ 21 6.1 Application Scenarios ..................................................................................... 21 6.2 Configuration Description................................................................................ 21 6.3 Network Impact ............................................................................................... 22

7 Abbreviation .................................................................................................. 22

8 Reference Document .................................................................................... 23


ZTE Confidential Proprietary © 2010 ZTE CORPORATION. All rights reserved. III

FIGURES

Figure 4-1 Configuring Dynamic HR Channel Allocation 1 ................................................... 6




Figure 4-5 Configuring Dynamic HR Channel Allocation 5 ................................................. 10

Figure 4-6 Configuring Dynamic HR Channel Allocation 6 ................................................. 11

TABLES

Table 4-1 Parameter List ...................................................................................................... 4

Table 5-1 Related Counters ............................................................................................... 11

ZTE Confidential Proprietary © 2010 ZTE CORPORATION. All rights reserved. II

Document Title


ZTE Confidential Proprietary © 2010 ZTE CORPORATION. All rights reserved. 1

1 Feature Attribute

iBSC Version: [iBSC V6.20]

BTS Version: [No requirements of BTS hardware platform]

Property: [Optional]

Related Network Elements and Requirements:

NE Name Related or Not Special Requirements

MS

BTS

BSC √

MSC -

MGW -

SGSN -

GGSN -

HLR -

Dependency: [ZGO-01-01-001 Half Rate]

Exclusive Function: [None]

Note: [None]

2 Overview

2.1 Feature Introduction

The dynamic half rate allocation function allows the network to allocate the full rate

channel or half rate channel for MSs according to traffic of a cell. When the channel of a

cell may be congested, the system starts to allocate the HR channel to suspend the

possible cell congestion of the traffic peak to the maximum extent.



2.2 Correlation with Other Features

This feature is related with basic feature ZGO-01-01-001 Half Rate, optional features

ZGO-01-01-003 Adaptive Multi-rate Codec (AMR) and ZGO-03-02-006 Independent

Threshold for Dynamic AMR HR/FR Conversion.

3 Technical Description

The dynamic half rate allocation allows the network to allocate the speech traffic channel

according to the current load of the cell. When the cell load is low, the full rate channel is

allocated for MSs to provide the better conversation quality. In the case of the traffic peak,

the cell load is high. To reduce the possibility of the cell congestion, partial conversation

quality is sacrificed and the half rate channel is allocated for MSs.

The dynamic half rate allocation function refers to the allocation of the TCH channel from

the cell when the cell load is high and the cell TCH occupation rate meets the configured

dynamic half rate conversion threshold while a new MS is accessed. In this case, the

system starts the dynamic half rate channel allocation function. To avoid the cell

congestion, the network allocates the half rate channel for MSs. Whether to allocate the

half rate channel to a MS depends on whether the accessed MSs support the half rate

channel. If MSs support the half rate channel, the applied channel type in the assignment

request or handover request contains the half rate channel type. The network allocates

the half rate channel for MSs if possible. If MSs do not support the half rate channel, the

applied channel type in the assignment request or handover request indicates only the

full rate channel is supported. In this case, the network allocates the full rate channel for

MSs to ensure the success ratio of the assignment and handover. When the cell load is

low and the cell TCH occupation ratio is smaller than the dynamic half rate conversion

threshold defined in the cell, the network disables the dynamic half rate channel

allocation function. It is subject to the normal wireless allocation policy for the distribution.

The support capability of MS for the half rate channel is contained the classmark update

reported to the MSC when the MS accesses the network. Hence, the MSC contains the

information that whether the MS supports the half rate channel information in the

assignment request.



In addition, one important parameter for implementing the dynamic half rate allocation

function is the cell busy level. The meaning of this parameter: Number of TCH channels

occupied in the cell/Number of all available TCH channels in the cell. The number of TCH

channels occupied in the cell includes all TCH/F and TCH/H occupied in the CS service

and PS service channels used for dynamically converting the TCH/F to the PDCH

(excluding static PDCH channels configured in the background). The number of all

available TCH channels in the cell includes all IDLE and BUSY channels, excluding

BLOCK channels (including unused channels due to too large uplink interferences). The

available TCH channel is the same as the above, including all TCH/F and TCH/H

channels and channels converting dynamically from TCH/F to PDCH.

The dynamic half rate conversion threshold refers to the cell busy threshold.

At present, the dynamic half rate allocation is applicable to the allocation of TCH

channels only. When MSs apply for the PDTCH in a PS service, the half rate allocation of

the PDTCH is not considered.

In channel priority property, if HR preferred is selected, even if HR conversion threshold

is not reached, HR channel will also be allocated if supporting dynamic HR.

Except HR dynamic conversion threshold, this feature also contains HR timeslot

percentage threshold “HRTsPercentage”, which includes BSC level and cell level. If HR

or AMR dynamic conversion threshold “HRThs” is sufficed, but current HR timeslot

threshold reaches or surpasses that of preset BSC level or cell level, HR dynamic

conversion is prohibited. HR timeslot percentage= (HR channel configured statically by

cell – blocked HR channel + dynamic idle HR channel + dynamic busy HR channels)/2 *

available timeslot numbers in cell.

Another AMR HR threshold is also classified into BSC levelBSCL and cell level. AMR HR

conversion threshold is smaller than that of HR, when reaching AMR conversion

threshold and cell supporting AMR TRX, cell phone supporting AMR speech version,

then HR channel will be distributed; while if AMR HR threshold is reached, but cell not

supporting AMR TRX or cell phone not supporting AMR speech version, HR channel

won’t be allocated. Idea of AMR HR conversion threshold is similar as HR conversion

threshold.



4 Parameters and Configurations

4.1 Parameter List

Table 4-1 Parameter List

Full name Dynamic HR Enable

Abbreviation DynaHREnable

Description If this cell supports dynamic HR.

Value Range Yes/No

Unit None

Default No (Set YES to activate this feature)

Management Object Cell

Full name Threshold for TRX switched from FR to HR (BSC)

Abbreviation HRThs

Decription

When channel occupation exceeds this threshold, it will

apply for half-rate channel directly to increase the user

capacity.

Value Range 1 ~ 100

Unit %

Default 60

Management Object BSC

Full name Use cell dynamic HR parameter

Abbreviation UseCellDynHRPara

Description It indicates use cell dynamic HR parameter.

Value Range Yes/No

Unit None

Default No (Set YES if need set dynamic HR parameter on cell

basis)


Full name Threshold for a single trx switched from FR to HR



Abbreviation HRThs

Description When BSC and cell enables dynamic HR functions,

and percentage of TCH/F channel used in the cell

(TCH/F channels occupied in the cell / all available

TCH channels in the cell (including IDLE and BUSY))

exceeds this threshold, convert TCH/F -> TCH/H.

Value Range 1 ~ 100

Unit %

Default 60


Full name HR channel percentage threshold (BSC)

Abbreviation HRTsPercentage

Description When HR timeslot in the cell / general timeslot

in the cell < HRTsPercentage/100, the cell can

generate new HR channel.

This parameter can be configured on BSC and

BTS. If the proportion of HR timeslot in the cell is

lower than HRTsPercentage/100 of BSC and BTS,

the cell can generate new HR channel.

Value Range 1 ~ 100

Unit %

Default 50

Management Object BSC

Full name Percentage of HR Ts (Cell)

Abbreviation HRTsPercentage

Description When HR timeslot in the cell / general timeslot

in the cell < HRTsPercentage/100, the cell

can generate new HR channel.

This parameter can be configured on BSC and

BTS. If the proportion of HR timeslot in the cell is

lower than HRTsPercentage/100 of BSC and BTS,

the cell can generate new HR channel.

Value Range 1 ~ 100

Unit %



Default 50


4.2 Parameter Configuration

1. In the configuration resource tree window, select OMC → GERAN Subnetwork

→ BSC Managed Element → Config Set →Create → BSC Function], show as

following figure:

Figure 4-1 Configuring Dynamic HR Channel Allocation 1



2. Click BSC Function, in Radio Basic Property tab set Dynamic HR enable to

Yes, and set value of Threshold for TRX switched from FR to HR, that is, only if the HR

threshold of any cell which busy level outreaches BSC level, and Support Dynamic HR

parameter is set to Yes of the BSC, the cell will activate dynamic HR conversion, as

shown in following figure:


3. In the navigation tree, right click [[OMC → GERAN Subnetwork → BSC Managed

Element → Config Set → BSC Function → Site Config → BTS ID→Create→Cell], show

as following figure:




4. Click Cell, in Create Cell -> Basic Params 1 tab (click to unfold all sub tabs),

set Dynamic HR support indication and Use cell dynamic HR parameter to Yes, and

Threshold for a single trx switched from FR to HR. That is, under the premise of setting

Yes for Support Dynamic HR in BSC, if set Support Dynamic HR Params and Activate

Cell Dynamic HR Params to Yes, the HR conversion threshold adopted by dynamic HR

feature refers to the cell’s HR conversion threshold, while not the BSC’s. when busy level

of cell reaches HR conversion threshold, then dynamic HR conversion will be turned on.

As shown in following figure:




5. In the configuration resource tree window, select [OMC → GERAN Subnetwork →

BSC Managed Element → Config Set →Create → BSC Function], set HR channel

percentage threshold of the whole BSC.




6. In the navigation tree, right click [[OMC → GERAN Subnetwork → BSC Managed

Element → Config Set → BSC Function → Site Config → BTS ID→Create→Cell], set HR

channel percentage threshold of the cell.




5 Related Counters and Alarms

5.1 Related Counters

Table 5-1 Related Counters

Counter ID What It Counts

C900060038 Number of signaling TCH/H seizure attempts for assignment

C900060039 Number of signaling TCH/H seizure failure for assignment

C900060040 Number of signaling TCH/H seizure attempts for handover

C900060041 Number of signaling TCH/H seizure failure for handover

C900060042 Number of voice TCH/H seizure attempts for assignment



C900060043 Number of voice TCH/H seizure failure for assignment

C900060044 Number of voice TCH/H seizure attempts for handover

C900060045 Number of voice TCH/H seizure failure for handover

C900060046 Number of data TCH/H seizure attempts for assignment

C900060047 Number of data TCH/H seizure failure for assignment

C900060048 Number of data TCH/H seizure attempts for handover

C900060049 Number of data TCH/H seizure failure for handover

C900060055 Number of TCH/H drops

C900060061 Average number of idle TCH/H with interference band 1





C900060121 Maximum number of busy TCH/H

C900060127 TCH/H busy time

C900060135 Number of signaling TCH/H assignment failure

C900060151 Number of voice TCH/H drops due to handover failure

C900060155 Number of available defined TCH/H

C900060174 Number of signaling TCH/H allocation failure for assignment

C900060175 Number of TCH/H allocation failure due to channel activation failure

for assignment (speech version1)

C900060176 Number of TCH/H allocation failure due to BTS connection failure for

assignment (speech version1)

C900060177 Number of TCH/H allocation failure due to BIU connection failure for


C900060178 Number of TCH/H allocation failure due to TCU connection failure for



for handover (speech version1)


handover (speech version1)







































C900060199 Number of Voice TCH/H assignment success

C900060200 Number of Voice TCH/H assignment failure



C900060201 Number of Voice TCH/H handover success

C900060202 Number of data TCH/H allocation failure due to channel activation

failure for assignment

C900060203 Number of data TCH/H allocation failure due to BTS connection failure

for assignment

C900060204 Number of data TCH/H allocation failure due to BIU connection failure

for assignment

C900060205 Number of data TCH/H allocation failure due to TCU connection

failure for assignment

C900060206 Number of data TCH/H allocation failure due to channel activation

failure for handover

C900060207 Number of data TCH/H allocation failure due to BTS connection failure

for handover

C900060208 Number of data TCH/H allocation failure due to BIU connection failure

for handover

C900060209 Number of data TCH/H allocation failure due to TCU connection

failure for handover

C900060210 Number of data TCH/H assignment success

C900060211 Number of data TCH/H assignment failure

C900060212 Number of data TCH/H handover success

C900060217 Number of unavailable defined TCH/H

C900060222 Number of signaling TCH/H drops due to handover failure

C900060223 Number of data TCH/H drops due to handover failure

C900060224 Number of TCH/H handover attempts due to UL strength

C900060225 Number of TCH/H handover attempts due to DL strength

C900060226 Number of TCH/H handover attempts due to UL quality

C900060227 Number of TCH/H handover attempts due to DL quality

C900060228 Number of TCH/H handover attempts due to UL interference

C900060229 Number of TCH/H handover attempts due to DL interference

C900060230 Number of TCH/H handover attempts due to good C/I

C900060231 Number of TCH/H handover attempts due to bad C/I

C900060232 Number of TCH/H handover attempts due to PBGT

C900060233 Number of TCH/H handover attempts due to large TA

C900060234 Number of TCH/H handover attempts due to other reasons



C900060235 Number of signaling TCH/H assignment success

C901060058 Number of TCH/H handover attempts due to quick break up of UL

C901060059 Number of TCH/H handover attempts due to macro-micro switch

C901060060 Number of TCH/H handover attempts due to MSC request

C901060061 Number of TCH/H handover attempts due to traffic

C901060062 Number of TCH/H handover attempts due to large TA and wastage

C901060063 Number of TCH/H handover attempts due to small TA and wastage

C901060064 Number of TCH/H handover attempts due to a preferable electricity

level in 3G adjacent cell

C901060065 Number of TCH/H handover attempts due to forced transfer

C901060066 Number of TCH/H handover attempts during assignment due to forced

transfer

C901060067 Number of TCH/H handover attempts during handover due to forced

transfer

C901060068 Number of TCH/H handover attempts during handover due to TA

increase

C901060069 Number of TCH/H handover attempts during handover due to TA

decrease

C901060070 Number of TCH/H handover attempts due to other reasons

C901070029 Number of signaling TCH/H drops due to loss of contact with RANA

C901070030 Number of signaling TCH/H drops due to radio link failure

C901070031 Number of signaling TCH/H drops due to LAPD link failure

C901070032 Number of signaling TCH/H drops due to OMC-R forced release

C901070033 Number of signaling TCH/H drops due to forced release by other calls

C901070035 Number of signaling TCH/H drops due to other failure

C901070036 Number of voice TCH/H drops due to loss of contact with RANA

C901070038 Number of voice TCH/H drops due to LAPD link failure

C901070039 Number of voice TCH/H drops due to OMC-R forced release

C901070040 Number of voice TCH/H drops due to forced release by other calls

C901070042 Number of voice TCH/H drops due to other failure

C901070043 Number of data TCH/H drops due to loss of contact with RANA

C901070044 Number of data TCH/H drops due to radio link failure

C901070045 Number of data TCH/H drops due to LAPD link failure



C901070046 Number of data TCH/H drops due to OMC-R forced release

C901070047 Number of data TCH/H drops due to forced release by other calls

C901070049 Number of data TCH/H drops due to other failure

C901070055 Number of TCH/H link failures

C901070058 Number of RANA link releases due to other cause on TCH/H

C901070060 Number of TCH/F short messages drops

C901070061 Number of TCH/H short messages drops

C901080014 Average number of busy TCH/H

C901080016 TCH/H busy time(SpeechVer1)

C901080017 TCH/H busy time(SpeechVer3)

C901080018 TCH/H congestion time

C901090125 Number of intra-cell TCH/F-to-TCH/H handover

C901090126 Number of intra-cell TCH/F-to-TCH/H handover success

C901090127 Number of intra-cell handover attempts from TCH/H

C901090128 Number of intra-cell TCH/H-to-TCH/F handover

C901090129 Number of intra-cell TCH/H-to-TCH/F handover success

C901090130 Number of intra-cell TCH/H-to-TCH/H handover

C901090131 Number of intra-cell TCH/H-to-TCH/H handover success

C901090135 Number of inter-cell TCH/F-to-TCH/H handover

C901090136 Number of inter-cell TCH/F-to-TCH/H handover success

C901090137 Number of inter-cell handover attempts from TCH/H

C901090138 Number of inter-cell TCH/H-to-TCH/F handover

C901090139 Number of inter-cell TCH/H-to-TCH/F handover success

C901090140 Number of inter-cell TCH/H-to-TCH/H handover

C901090141 Number of inter-cell TCH/H-to-TCH/H handover success

C901120024 Mean number of idle TCH/Hs with interference band 0

C901130003 Number of available TCH/Hs in the second sub cell

C901130004 Number of unavailable TCH/Hs in the second sub cell

C901130051 Number of TCH/H seizure attempts of the second sub cell (used for

assignment)

C901130052 Number of TCH/H seizure success of the second sub cell (used for

assignment)



C901130053 Number of TCH/H seizure failure of the second sub cell (used for

assignment)

C901130054 Number of TCH/H seizure attempts of the second sub cell (used for

handover)

C901130055 Number of TCH/H seizure success of the second sub cell (used for

handover)

C901130056 Number of TCH/H seizure failure of the second sub cell (used for

handover)

C901130058 Number of TCH/H call drops in the second sub cell

C901130060 TCH/H busy time in the second sub cell

C901230016 Number of TCH/H activation attempts (including handover)

C901230017 Number of TCH/H activation success (including handover)

C901230018 Number of TCH/H assignment attempts

C901230019 Number of TCH/H assignment success







C901270002 Number of signaling TCH/H seizure success for assignment

C901270005 Number of signaling TCH/H seizure success for handover

C901270007 Number of signaling TCH/H allocation attempts by BSC for

assignment

C901270008 Number of signaling TCH/H allocation success for assignment

C901270010 Number of signaling TCH/H allocation attempts by BSC due to

handover

C901270011 Number of signaling TCH/H allocation success due to handover

C901270012 Number of signaling TCH/H allocation failure due to handover

C901270013 Number of signaling TCH/H assignment attempts by BSC

C901270016 Number of signaling TCH/H handover attempts

C901270017 Number of signaling TCH/H handover success

C901270018 Number of signaling TCH/H handover failure



C901270019 Number of signaling TCH/H handover failure messages do not

received by BSC

C901270021 Number of voice TCH/H seizure success for assignment

C901270024 Number of voice TCH/H seizure success for handover

C901270026 Number of TCH/H allocation attempts for assignment by BSC (speech

version 1)


for assignment (speech version 1)

C901270032 Number of TCH/H allocation attempts by BSC during handover

(speech version 1)

C901270033 Number of TCH/H allocation success during handover (speech

version 1)

C901270038 Number of TCH/H allocation attempts by BSC for assignment (speech

version 2)

C901270039 Number of TCH/H allocation success by BSC for assignment (speech

version 2)

C901270044 Number of TCH/H allocation attempts for handover by BSC (speech

version 2)

C901270045 Number of TCH/H allocation success for handover (speech version 2)

C901270050 Number of TCH/H allocation attempts for assignment (speech version

3)

C901270051 Number of TCH/H allocation success for assignment (speech version

3)

C901270056 Number of TCH/H allocation attempts by BSC for handover (speech

version 3)

C901270057 Number of TCH/H allocation success for handover (speech version 3)

C901270062 Number of Voice TCH/H assignment attempts by BSC

C901270065 Number of Voice TCH/H handover attempts

C901270067 Number of Voice TCH/H handover failure

C901270068 Number of Voice TCH/H handover failure messages do not received

by BSC

C901270070 Number of data TCH/H seizure success for assignment

C901270073 Number of data TCH/H seizure success for handover

C901270075 Number of data TCH/H allocation attempts for assignment by BSC

C901270076 Number of data TCH/H allocation success for assignment



C901270081 Number of data TCH/H allocation attempts by BSC

C901270082 Number of data TCH/H allocation success for handover

C901270087 Number of data TCH/H assignment attempts by BSC

C901270090 Number of data TCH/H handover attempts

C901270092 Number of data TCH/H handover failure

C901270093 Number of data TCH/H handover failure do not received by BSC

C901270094 Number of TCH/H allocation failure for assignment due to TIPB

connection failure (Speech version 1)

C901270095 Number of TCH/H allocation failure for assignment due to Resource

request to iTC failure (Speech version 1)

C901270096 Number of TCH/H allocation failure for handover due to TIPB


C901270097 Number of TCH/H allocation failure for handover due to Resource


















C901270106 Number of TCH/H allocation failure due to request AIPB resource

failure for assignment (speech version 1)

C901270107 Number of TCH/H allocation failure due to request UDP port failure for

assignment (speech version 1)



C901270108 Number of TCH/H allocation failure due to AIPB connection failure for



failure for handover (speech version 1)


handover (speech version 1)




























failure for assignment (data)


assignment (data)




assignment (data)


failure for handover (data)


handover (data)


handover (data)

5.2 Related Alarms

None

6 Engineering Guide

6.1 Application Scenarios

HR reduces speech quality objectively. For key areas such as dense urban where has a

high utilization of HR adoption, capacity problem should be addressed by network

expansion or cell splitting as early as possible. Dynamic HR normally is applied in

following scenarios:

To alleviate outburst traffics in holidays;

Cells with high outburst traffics;

Cells can not be expanded. With limit frequency points, activating dynamic HR increases

cell channels capacity.

6.2 Configuration Description

This feature does not involve iBSC and BTS hardware configuration adjustment.



6.3 Network Impact

Impacts on network performance from this feature can be analyzed by STS (such as

call drop times, congestion level, access indices changes, and data channel allocation in

speech channel), MRR and DT test. Specifically, this feature influences the network in

following aspects:

Improve BTS capacity, TRX max channel quantity can be doubled;

In better radio environment, dynamic HR has no impacts on call drop rate and traffic

drop rate; it enhances call success rate and handover success rate a little, apparently

decrease congestion ratio;

By DT test, SQI and RXQUAL become worse obviously after activating dynamic HR

under the same radio environment, and speech quality during conversation is dropped; in

worse C/I environment, compared with FR, HR speech quality falls a lot;

Therefore, HR can effectively resolve the heavy traffic problems. But if it desires to

keep better performance, current radio environment needs to be optimized, especially for

interference (after activating HR, encoding style of HR and FR is different, which causes

channel error correcting capability decrease under the same environment), then

requirements on network planning such as frequency planning and BTS coverage control

are boosted.

7 Abbreviation

Abbreviations Full Characteristics

AMR Adaptive Multi-Rate

BSC Base Station Controller

BTS Base Transceiver Station

FR Full Rate

GERAN Gsm/Edge Radio Access Network

GSM Global System for Mobile communications



HR Half Rate

MS Mobile Station

OMC Operation & Maintenance Center

SACCH Slow Associated Control Channel

SDCCH Stand alone dedicated Control Channel

TCH Traffic Channel

TDMA Time Division Multiplex Access

8 Reference Document

[None]

Documents

ZGO-03!02!005 Dynamic Half Rate Allocation FG 20101030