Directed Retry Decision 3G Huawei

Huawei Proprietary and Confidential

Copyright © Huawei Technologies Co., Ltd.

WCDMA RAN

Directed Retry Decision Feature Parameter Description

Copyright © Huawei Technologies Co., Ltd. 2011. All rights reserved.

No part of this document may be reproduced or transmitted in any form or by any means without prior written consent of Huawei Technologies Co., Ltd.

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and other Huawei trademarks are the property of Huawei Technologies Co., Ltd. All other trademarks and trade names mentioned in this document are the property of their respective holders.

Notice

The purchased products, services and features are stipulated by the commercial contract made between Huawei and the customer. All or partial products, services and features described in this document may not be within the purchased scope or the usage scope. Unless otherwise agreed by the contract, all statements, information, and recommendations in this document are provided "AS IS" without warranties, guarantees or representations of any kind, either express or implied.

The information in this document is subject to change without notice. Every effort has been made in the preparation of this document to ensure accuracy of the contents, but all statements, information, and recommendations in this document do not constitute a warranty of any kind, express or implied.

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Directed Retry Decision Contents

Issue 01 (2011-04-30) Huawei Proprietary and Confidential


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Contents

1 Introduction ................................................................................................................................ 1-1

1.1 Scope ............................................................................................................................................ 1-1

1.2 Intended Audience ........................................................................................................................ 1-1

1.3 Change History .............................................................................................................................. 1-1

2 Overview of DRD ....................................................................................................................... 2-1

3 RRC DRD ..................................................................................................................................... 3-1

4 Non-Periodic DRD ..................................................................................................................... 4-1

4.1 Overview ....................................................................................................................................... 4-1

4.2 Blind-Handover-Based Non-Periodic DRD ................................................................................... 4-1

4.3 Inter-Frequency DRD .................................................................................................................... 4-1

4.4 DRD for Technological Satisfaction ............................................................................................... 4-3

4.4.1 Overview ............................................................................................................................... 4-3

4.4.2 Priority Sequence of HSPA+ Technologies .......................................................................... 4-3

4.4.3 Procedure for DRD for Technological Satisfaction ............................................................... 4-4

4.5 Inter-Frequency DRD for Service Steering ................................................................................... 4-5

4.5.1 Cell Service Priorities ........................................................................................................... 4-5

4.5.2 Procedure for DRD for Service Steering .............................................................................. 4-6

4.6 Inter-Frequency DRD for Load Balancing ..................................................................................... 4-7

4.6.1 Overview of DRD for Load Balancing ................................................................................... 4-8

4.6.2 Power-Based DRD for Load Balancing ................................................................................ 4-8

4.6.3 Code-Based DRD for Load Balancing ................................................................................ 4-12

4.7 Inter-RAT DRD ............................................................................................................................ 4-14

4.8 Measurement-Based Non-Periodic DRD .................................................................................... 4-15

4.8.1 Overview ............................................................................................................................. 4-15

4.8.2 MBDR Algorithm Switches ................................................................................................. 4-15

4.8.3 MBDR Procedure ............................................................................................................... 4-15

5 Periodic DRD .............................................................................................................................. 5-1

5.1 Overview ....................................................................................................................................... 5-1

5.1.1 Switches for Periodic DRD ................................................................................................... 5-1

5.1.2 Triggering Periodic DRD ....................................................................................................... 5-1

5.2 Periodic DRD Procedure ............................................................................................................... 5-2

5.2.1 Blind-Handover-Based Periodic DRD .................................................................................. 5-2

5.2.2 Measurement-Based Periodic DRD ..................................................................................... 5-3

6 Parameters ................................................................................................................................. 6-1

7 Counters ...................................................................................................................................... 7-1

8 Glossary ...................................................................................................................................... 8-1

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9 Reference Documents ............................................................................................................. 9-1

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Directed Retry Decision 1 Introduction



1-1

1 Introduction

1.1 Scope

This document describes the Directed Retry Decision (DRD) feature. It covers both the RRC DRD and the RAB DRD, and also provides parameter descriptions for both functions.

1.2 Intended Audience

This document is intended for:

Personnel who are familiar with WCDMA basics

Personnel who need to understand DRD

Personnel who work with Huawei products

1.3 Change History

This section provides information on the changes in different document versions.

There are two types of changes, which are defined as follows:

Feature change: refers to the change in the DRD feature.

Editorial change: refers to the change in wording or the addition of the information that was not described in the earlier version.

Document Issues

The document issues are as follows:

01 (2011-04-30)

Draft B (2011-03-30)

Draft A (2010-12-30)

01 (2011-04-30)

This is the document for the first commercial release of RAN13.0.

Compared with Draft B (2011-03-30) of RAN13.0, this issue optimizes the description.

Draft B (2011-03-30)

This is the draft of the document for RAN13.0.

Compared with Draft A (2010-12-30) of RAN13.0, this issue optimizes the description.

Draft A (2010-12-30)

This is the draft of the document for RAN13.0.

Compared with issue 03 (2010-12-20) of RAN12.0, this issue optimizes the description of uplink load balancing for DC-HSDPA services. For details, see 4.6.2 "Power-Based DRD for Load Balancing."

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Directed Retry Decision 2 Overview of DRD



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2 Overview of DRD

DRD is used to select a suitable cell for a UE to access. Different types of DRD can be adopted during different phases of service processing. In this way, the system capacity is maximized, and better services are provided.

Figure 2-1 shows the different types of DRD.

Figure 2-1 Types of DRD

RAB DRD is performed during the RAB phase, which starts with RAB setup processing and ends with RAB release. There are two types of RAB DRD: non-periodic DRD and periodic DRD.

The description of the DRD types is listed in Table 2-1.

Table 2-1 DRD type descriptions

DRD Type Application Scenario

Description

RRC DRD During RRC setup

RRC DRD is used to select a suitable inter-frequency neighboring cell in which a UE can set up an RRC connection in either of the following situations:

The RRC connection setup fails in the cell that the UE tried to access.

The cell that the UE is trying to access does not support signaling radio bearer (SRB) over HSPA when it is selected as the bearer scheme.

RRC DRD is based on blind handover.

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DRD Type Application Scenario

Description

Non-periodic DRD

During RAB setup, RAB modification, or DCCC channel reconfiguration

Non-periodic DRD can be blind-handover-based or measurement-based.

Blind-handover-based non-periodic DRD is used to select a suitable cell for a UE to access according to HSPA+ technological satisfaction, service priority, and cell load. It enables the UE to be served with the best technological satisfaction and implements service steering and load balancing.

Measurement-based non-periodic DRD, or Measurement-Based Directed Retry (MBDR), is used to select a cell with qualifying signals for a UE to access according to the measurement result of signal quality. Compared with blind-handover-based non-periodic DRD, MBDR increases DRD success rate when the current cell and the DRD target cell cover different areas.

Blind-handover-based non-periodic DRD and MBDR cannot work concurrently. When MBDR is enabled, blind-handover-based non-periodic DRD is automatically disabled.

Periodic DRD

After RAB setup or after the bearer scheme is changed

Periodic DRD is used to select a suitable cell according to device type priority, technological satisfaction, and service priority. It can be performed when the RNC determines that the UE can be served by a better HSPA/HSPA+ technology or when a neighboring cell has a higher service priority than the current cell.

After periodic DRD is triggered, it can be performed in either of the following ways:

Blind-handover-based periodic DRD: This mainly applies to the inter-frequency co-coverage scenario. It selects the target cell that supports blind handovers and does not consider the signal quality of the target cell.

Measurement-based periodic DRD: This applies to both the inter-frequency different-coverage and the inter-frequency co-coverage scenarios. It selects the target cell according to the signal measurement results. Note that only measurement-based periodic DRD is based on cell service priority.

Blind-handover-based periodic DRD and measurement-based periodic DRD cannot work concurrently. When the latter is enabled, the former is automatically disabled.

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Directed Retry Decision 3 RRC DRD



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3 RRC DRD

RRC DRD is performed when a UE fails to access the current cell during RRC connection setup. The purpose is to enable the UE to set up an RRC connection in a suitable inter-frequency neighboring cell.

The DR_ RRC_DRD_SWITCH subparameter of the DrSwitch parameter determines whether RRC DRD is enabled.

The RRC DRD procedure is as follows:

1. The RNC selects intra-band inter-frequency neighboring cells of the current cell that are suitable for blind handovers. Whether a neighboring cell supports blind handovers is specified by the parameter BlindHoFlag.

2. The RNC generates a list of inter-frequency candidate cells that support DRD according to the following condition:

(CPICH_EcNo)RACH > DRD_EcNOnbcell

Here:

− (CPICH_EcNo)RACH is the cached CPICH Ec/N0 value included in the RACH measurement report. Note that this value is for the current cell.

− DRD_EcNOnbcell is the DRD threshold (specified by the DRDEcN0Threshhold parameter) of the neighboring cell.

3. The RNC selects a target cell from the candidate cells for UE access. If the candidate cell list is empty, RRC DRD fails. The RNC performs RRC redirection. If the candidate cell list contains more than one cell, the UE tries a cell randomly.

− If the UE is granted access, the RNC continues the RRC connection setup procedure.

− If the UE is not granted access, the UE tries to access another cell in the candidate cell list until it successfully accesses a cell or all access attempts fail.

If all access attempts fail, then

− The RNC makes an RRC redirection decision, provided that the function of RRC redirection after DRD failure is enabled.

− The RRC connection setup fails if the function of RRC redirection after DRD failure is disabled.

For information about RRC redirection after DRD failure, see the Load Control Feature Parameter Description.

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Directed Retry Decision 4 Non-Periodic DRD



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4 Non-Periodic DRD

This section covers the following features:

WRFD-02040001 Intra System Direct Retry

WRFD-02040002 Inter System Direct Retry

WRFD-01061112 HSDPA DRD

WRFD-020402 Measurement-based Direct Retry

4.1 Overview

Non-periodic DRD is used to select a suitable cell for UE access. It can be performed during a RAB setup, RAB modification, or DCCC.

Non-periodic DRD can be measurement-based or blind-handover-based. Blind-handover-based non-periodic DRD and measurement-based non-periodic DRD (MBDR) cannot be used simultaneously. When MBDR is enabled, other types of non-periodic DRDs are disabled automatically.

For detailed information about blind-handover-based non-periodic DRD, see section 4.2 "Blind-Handover-Based Non-Periodic DRD."

For detailed information about measurement-based non-periodic DRD, see section 4.8 "Measurement-Based Non-Periodic DRD."

4.2 Blind-Handover-Based Non-Periodic DRD

Blind-handover-based non-periodic DRD consists of inter-frequency DRD (WRFD-02040001 Intra System Direct Retry) and inter-RAT DRD (WRFD-02040002 Inter System Direct Retry).

When MBDR is disabled, the following parameters determine whether to enable blind-handover-based non-periodic DRD:

For a single service, blind-handover-based non-periodic DRD is enabled by the DR_RAB_SING_DRD_SWITCH subparameter of the DrSwitch parameter.

For combined services, blind-handover-based non-periodic DRD is enabled by the DR_RAB_COMB_DRD_SWITCH subparameter of the DrSwitch parameter.

Note that if the measurement-based periodic DRD switch BasedOnMeasHRetryDRDSwitch is set to ON, blind-handover-based non-periodic DRD is also controlled by the BlindDrdExceptHRetrySwitch parameter.

For example, if MBDR is disabled, the DR_RAB_SING_DRD_SWITCH subparameter of the DrSwitch parameter is set to ON, and the BasedOnMeasHRetryDRDSwitch parameter is set to ON, then blind-handover-based non-periodic DRD for a single service is enabled only if the BlindDrdExceptHRetrySwitch parameter is also set to ON.

For detailed information about inter-frequency DRD, see section 4.3 "Inter-Frequency DRD."

For detailed information about inter-RAT DRD, see section 4.7 "Inter-RAT DRD."

4.3 Inter-Frequency DRD

An inter-frequency DRD procedure consists of DRD for device type steering, DRD for technological satisfaction, DRD for service steering, and DRD for load balancing. The RNC performs these DRDs in sequence, as shown in Figure 4-1.



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Figure 4-1 Performing DRDs in sequence

The RNC does not consider disabled DRD functions. For example, if DRD for load balancing is disabled, the RNC does not consider the cell load when selecting a cell based on inter-frequency DRD.

DRD for device type steering is controlled by the parameter DPGDRDSwitch. During RAB access, the RNC first selects a cell with the highest device type priority for the UE according to the DRD for device type steering. If multiple cells have the highest device type priority, the RNC selects a suitable cell based on DRD for technological satisfaction, DRD for service steering, and DRD for load balancing. For details about DRD for device type steering, see the Intelligent Inter-Carrier Layered Management on UEs and Data Cards Feature Parameter Description.

DRD for HSPA+ technological satisfaction is efficient, but it is applicable only to UEs requesting HSPA+ services. DRD for service steering and DRD for load balancing are controlled by related parameters.

If all the DRD functions are enabled, the inter-frequency DRD procedure is as follows:

1. The RNC determines the candidate cells to which a blind handover can be performed. Whether the neighboring cells support blind handover is specified by the parameter BlindHoFlag. A candidate cell must meet the following conditions:

− The candidate cell supports the requested service.

− The frequency of the candidate cell is in the band supported by the UE.

− The current cell meets the quality requirements of inter-frequency DRD. For details, see 3 "RRC DRD."

The current cell is also considered as a candidate if it supports the requested service.

2. The RNC selects a target cell from the candidate cells for UE access as follows:

(1) The RNC selects a cell with the highest technological satisfaction as described in section 4.4 "DRD for Technological Satisfaction."

(2) If multiple cells have the highest technological satisfaction or the requested service is not an HSPA+ one, the RNC selects a cell based on DRD for service steering as described in section 4.5 "Inter-Frequency DRD for Service Steering."

(3) If multiple cells have the highest service priority, the RNC selects a cell based on DRD for load balancing as described in section 4.5 "Inter-Frequency DRD for Service Steering."

3. The call admission control (CAC) algorithm makes an admission decision based on the resource status of the cell.

− If the admission attempt is successful, the RNC initiates an inter-frequency blind handover to the cell.

− If the admission attempt fails, the RNC removes the cell from the list of candidate cells and then checks whether all candidate cells have been tried.

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a. The algorithm goes back to step 2 to try any candidate cells that have not been tried.

b. If all candidate cells haven been tried and

− If the service request is an HSPA one, then the HSPA request is demoted to a DCH request and the algorithm goes back to step 1 to retry admission based on R99 service priorities.

− If the service request is a DCH one, then the RNC initiates an inter-RAT DRD.

For UEs requesting non-HSPA+ services, if both DRD for service steering and DRD for load balancing are disabled, the RNC performs the following steps:

1. The UE attempts to access the current cell if its service priority is not 0. If the service priority of the current cell is 0, the UE attempts to access a neighboring cell with the highest blind-handover priority. The blind handover priority of the cell is specified by the parameter BlindHOPrio.

2. The CAC algorithm makes an admission decision based on the cell status. For details about the CAC procedure, see the Call Admission Control Feature Parameter Description.

− If the admission attempt is successful, the RNC accepts the service request.

− If the admission attempt fails, the UE attempts to access another candidate cell.

3. If any request for access to a candidate cell is rejected and

− If the service request is an HSPA one, then the HSPA request is demoted to a DCH request and the algorithm goes back to step 1 to retry admission based on R99 service priorities.

− If the service request is a DCH one, the RNC initiates an inter-RAT DRD. For details about inter-RAT DRD, see section 4.7 "Inter-RAT DRD."

4.4 DRD for Technological Satisfaction

4.4.1 Overview

Technological satisfaction refers to determining whether a candidate cell satisfies the technical specifications for certain services, such as HSPA+ services. DRD for technological satisfaction is used to select a suitable cell and HSPA+ technologies for a UE based on the HSPA+ technologies supported by the UE and the attributes of the requested service, such as the bearer channel, service type, and service rate.

DRD for technological satisfaction consists of the following processes:

1. The RNC determines the HSPA+ technologies that can be configured on the UE, based on the HSPA+ technologies supported by the UE and attributes of the requested service, as described in

the Radio Bearers Feature Parameter Description.

2. The RNC determines the HSPA+ technological satisfaction of each candidate cell based on the priorities of HSPA+ technologies as well as the HSPA+ technologies that can be both configured on the UE and supported by the cell.

3. The RNC selects a suitable cell for the UE based on the priority sequence of HSPA+ technologies. The RNC also determines the HSPA+ technologies for the UE, which are the HSPA+ technologies that can be both configured on the UE and supported by the cell.

4.4.2 Priority Sequence of HSPA+ Technologies

The technological satisfaction of a cell is determined by the HSPA+ technologies that can be both configured on the UE and supported by the cell. If these HSPA+ technologies have a high priority, the cell is considered to have a high technological satisfaction.

The HSPA+ technologies comprise DC-HSDPA, enhanced layer 2 (L2), MIMO, 64QAM, DTX+DRX, E-DPCCH Boosting, UL 16QAM, and HS-SCCH Less Operation. The priority sequences of the technologies in a cell supporting HSPA+ are as follows:

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When MIMO64QAMorDCHSDPASwitch is set to DC-HSDPA and MIMOor64QAMSwitch to MIMO, the priority sequence is DC-HSDPA+MIMO > DC-HSDPA (with downlink 64QAM activated in at least one cell) > MIMO+64QAM > DC-HSDPA (with downlink 16QAM activated in at least one cell) > MIMO+DL 16QAM > DL 64QAM > DL enhanced L2 > E-DPCCH Boosting > UL 16QAM > UL enhanced L2 > DTX+DRX > HS-SCCH Less Operation.

When MIMO64QAMorDCHSDPASwitch is set to DC-HSDPA and MIMOor64QAMSwitch to 64QAM, the priority sequence is DC-HSDPA+MIMO > DC-HSDPA (with downlink 64QAM activated in at least one cell) > MIMO+64QAM > DC-HSDPA (with downlink 16QAM activated in at least one cell) > DL 64QAM > MIMO+DL 16QAM > DL enhanced L2 > E-DPCCH Boosting >UL 16QAM > UL enhanced L2 > DTX+DRX > HS-SCCH Less Operation.

When MIMO64QAMorDCHSDPASwitch is set to MIMO_64QAM and MIMOor64QAMSwitch to MIMO, the priority sequence is DC-HSDPA+MIMO > MIMO+64QAM > DC-HSDPA (with downlink 64QAM activated in at least one cell) > MIMO+DL 16QAM > DL 64QAM > DC-HSDPA (with downlink 16QAM activated in at least one cell) > DL enhanced L2 > E-DPCCH Boosting > UL 16QAM > UL enhanced L2 > DTX+DRX > HS-SCCH Less Operation.

When MIMO64QAMorDCHSDPASwitch is set to MIMO_64QAM and MIMOor64QAMSwitch to 64QAM, the priority sequence is DC-HSDPA+MIMO > MIMO+64QAM > DC-HSDPA (with downlink 64QAM activated in at least one cell) > DL 64QAM > MIMO+DL 16QAM > DC-HSDPA (with downlink 16QAM activated in at least one cell) > DL enhanced L2 > E-DPCCH Boosting > UL 16QAM > UL enhanced L2 > DTX+DRX > HS-SCCH Less Operation.

4.4.3 Procedure for DRD for Technological Satisfaction

The procedure for DRD for technological satisfaction is as follows:

1. The RNC determines the candidate cells to which blind handovers can be performed. Whether the neighboring cells support blind handover is specified by the parameter BlindHoFlag. A candidate cell must meet the following conditions:





2. The RNC selects a cell with the highest technological satisfaction as the target cell. If multiple cells have the highest technological satisfaction, the RNC selects a suitable cell based on DRD for service steering. If multiple cells have the highest service priority, the RNC selects a suitable cell based on DRD for load balancing.

The RNC also determines the HSPA technologies for the UE in this step.

If the UE requires the DC-HSPA technology, the RNC searches for a DC-HSPA cell group based on the target cell. If multiple DC-HSPA cell groups have the highest technological satisfaction, the RNC selects a suitable cell group based on DRD for service steering. Then, if multiple cell groups have the highest service priority, the RNC selects a suitable cell group based on DRD for load balancing.

3. The CAC algorithm makes an admission decision based on the resource status of the cell or cell group.

− If the admission attempt is successful, the RNC initiates an inter-frequency blind handover to the cell or cell group.

− If the admission attempt fails, the RNC removes the cell or cell group from the list of candidate cells and then checks whether all candidate cells have been tried.

a. The algorithm goes back to step 2 to try any candidate cells that have not been tried.

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b. If all candidate cells have been tried and the service request is an HSPA one, the HSPA request falls back to a DCH one to retry admission based on R99 service priorities according to the DRD for service steering and load balancing.

One or two DC-HSDPA cells may support MIMO, depending on the configuration of the DC-HSDPA cells. Gains also vary according to whether the DC-HSDPA or MIMO technique is used. DC-HSDPA UEs have higher throughput in low-traffic cells, whereas MIMO UEs have higher throughput in high-traffic cells. Therefore, when both DC-HSDPA and MIMO are available, Huawei introduces the DC-HSDPA and MIMO dynamic selection algorithm to determine what technique will carry incoming services according to the current number of HSDPA UEs and the downlink load status of the cell. This algorithm selects the optimal technique for carrying services, thereby achieving higher throughput and improving user experience. For details about DC-HSDPA and MIMO dynamic selection, see the MIMO Feature Parameter Description.

4.5 Inter-Frequency DRD for Service Steering

This section describes the features WRFD-02040004 Traffic Steering and Load Sharing During RAB Setup.

If the UE requests a service in an area covered by multiple frequencies, the RNC selects the cell with the highest service priority for UE access, based on the RAB service type and the service priorities in the cells.

The availability of DRD for service steering is specified by the ServiceDiffDrdSwitch parameter through MML command SET UDRD (RNC level switch) or ADD UCELLDRD (cell level switch).

Inter frequency DRD for service steering can also be called inter-frequency DRD for traffic steering.

4.5.1 Cell Service Priorities

A cell service priority is a service-specific priority for a cell among cells in the same coverage area. Cell service priorities help achieve traffic absorption in a hierarchical way.

The service priorities of a cell are set as follows:

1. Run the ADD USPG command to add a service priority group, which is identified by SpgId. This group includes the service priorities of a cell.

2. Run the ADD UCELLSETUP, MOD UCELLSETUP, or ADD UCELLQUICKSETUP command to assign the SPG identity to the cell, that is, to set the service priorities for the cell.

The SPG to which a cell belongs is independent of DRD for service steering. For example, if the priority of a service is set to 0 in an SPG, this service cannot be established in the cells belonging to the SPG, regardless of whether DRD for service steering is activated or not.

When selecting a target cell for RAB processing, the RNC selects a cell with a high priority, that is, a cell that has a low service priority value.

The service priority groups given in the following table are defined on the RNC.

Cell SPG Identity

Service Priority of R99 RT Service

Service Priority of R99 NRT Service

Service Priority of HSDPA Service

Service Priority of HSUPA Service

Service Priority of Extension Services

A 1 2 1 1 1 0

B 2 1 2 0 0 0

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As shown in the following figure, cell B has a higher service priority for the R99 RT service than cell A. If the UE requests an R99 RT service in cell A, the RNC preferably selects cell B for the UE to access.

Figure 4-2 Example of DRD for service steering

If the requested service is a combined service, the RAB with the highest priority is used when a cell is selected for RAB processing. In addition, the target cell must support all of the necessary services.

4.5.2 Procedure for DRD for Service Steering

This section describes the procedure for DRD for service steering when DRD for load balancing is disabled.

Figure 4-3 Procedure for DRD for service steering

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The procedure for DRD for service steering is as follows:

1. The RNC determines the candidate cells and sorts them in descending order according to service priority.

A candidate cell must meet the following:

− The candidate cell supports blind handover. Whether the neighboring cells support blind handover is specified by the parameter BlindHoFlag.





If DRD for technological satisfaction is performed before DRD for service steering, the candidate cell must also meet the conditions based on which DRD for technological satisfaction is performed.

2. The RNC selects a target cell from among the candidate cells in order of service priority for the UE to access.

If there is more than one cell with the same service priority,

− The RNC preferentially selects a candidate cell with the same service priority for admission decision.

− Otherwise, the RNC randomly selects a cell as the target cell.

3. The CAC algorithm makes an admission decision based on the status of the target cell.

If the admission attempt is successful, the RNC accepts the service request.

If the admission attempt fails, the RNC removes the cell from the list of candidate cells and then checks whether all candidate cells have been tried.

− The algorithm goes back to step 2 to try any candidate cells that have not been tried.

− If admission decisions have been made for all the candidate cells, then:

a. If the service request is an HSPA one, the HSPA request is demoted to a DCH one. Then, the algorithm goes back to step 1 to make an admission decision based on R99 service priorities.

b. If the service request is a DCH one, the RNC initiates an inter-RAT DRD.

In the case of DC-HSDPA services, if multiple DC-HSDPA cell groups have the highest technological satisfaction, the RNC selects a cell group with the highest service priority.

The service priority of a DC-HSDPA cell group is determined by the highest service priority of the two cells.

4.6 Inter-Frequency DRD for Load Balancing

This section describes the feature WRFD-02040004 Traffic Steering and Load Sharing During RAB Setup.

If the UE requests a service setup or channel reconfiguration in an area covered by multiple frequencies, the RNC sets up the service on a carrier with a light load to balance out the load among the cells on the different frequencies.

Inter-frequency DRD for load balancing also can be called inter-frequency DRD for load sharing.

"Inter-frequency DRD for load balancing" is called "DRD for load balancing" for short in this section.

This section describes the procedure for performing DRD for load balancing when DRD for service steering is disabled.


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4.6.1 Overview of DRD for Load Balancing

DRD for load balancing concerns two resources: power and code.

The availability of DRD for load balancing is specified by associated parameters as follows:

The availability of power-based DRD for load balancing for DCH services is specified by the LdbDRDSwitchDCH parameter.

The availability of power-based DRD for load balancing for HSDPA services is specified by the LdbDRDSwitchHSDPA parameter.

The availability of code-based DRD for load balancing is specified by the CodeBalancingDrdSwitch parameter.

It is recommended that only power-based DRD for load balancing or code-based DRD for load balancing be activated. When both are activated, power-based DRD for load balancing takes precedence over code-based DRD for load balancing.

Code-based DRD for load balancing is applicable to only R99 services because HSDPA services use reserved codes.

4.6.2 Power-Based DRD for Load Balancing

For Non-DC-HSDPA Services

The following two algorithms are available for power-based load balancing. The algorithm used is specified by the LdbDRDchoice parameter.

Algorithm 1: DRD for load balancing is performed according to the cell measurement values for the DL non-HSDPA power and DL HS-DSCH GBP.

− The RNC sets up DCH services on a carrier with a light non-HSDPA power load to achieve load balancing among the cells at different frequencies.

− The RNC sets up the HSDPA services on a carrier with a light HS-DSCH GBP load to achieve load balancing among the cells at different frequencies.

Algorithm 2: DRD for load balancing is performed according to the DCH equivalent number of users (ENU) and HSDPA user number.

− The RNC sets up DCH services on a carrier with a light DCH ENU load to achieve load balancing among the cells on different frequencies.

− The RNC sets up HSDPA services on a carrier with a light HSDPA user load to achieve load balancing among the cells on different frequencies.

Figure 4-4 shows the procedure for power-based DRD for load balancing.

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Figure 4-4 Procedure for power-based DRD for load balancing

The procedure for power-based DRD for load balancing is as follows:

1. The RNC determines the candidate cells.

A candidate cell must meet the following . Note that target cell selection is also based on the resources of the DC-HSDPA cell group when the cell group is involved.






2. If the current cell is a candidate cell, the RNC proceeds to step 3. Otherwise, the RNC selects the cell with lightest load from the candidate cell list and goes to step 5.

3. The RNC determines whether the current cell meets the following condition (condition 1).


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− For algorithm 1, condition 1 is as follows:

a. For DCH services

(ThdAMR,cutcell - Pnon-H,cutcell) > Thdnon-H

Here,

ThdAMR,cutcell is specified by DlConvAMRThd.

Pnon-H,cutcell is the ratio of the non-HSDPA power load of the current cell to the total downlink load.

Thdnon-H is specified by LdbDRDLoadRemainThdDCH.

b. For HSDPA services

(Thdtotal,cutcell - PGBP,cutcell) > ThdH

Here,

Thdtotal,cutcell is specified by DlCellTotalThd.

PGBP,cutcell is the ratio of the HS-DSCH GBP load of the current cell to the total downlink load.

ThdH is specified by LdbDRDLoadRemainThdHSDPA.

− For algorithm 2, condition 1 is as follows:

a. For DCH services

(ThdAMR,cutcell - PD-enu,cutcell) > Thdnon-H

Here, PD-enu,cutcell is the ratio of the DCH ENU load of the current cell to the total downlink ENU load.

The total equivalent user number corresponding to the total downlink load is specified by DlTotalEqUserNum.

b. For HSDPA services

(ThdH-ue,cutcell - PH-ue,cutcell) / ThdH-ue,cutcell > ThdH

Here,

ThdH-ue,cutcell is specified by MaxHsdpaUserNum.

PH-ue,cutcell is the total number of HSDPA users of the current cell.

If... Then...

Condition 1 is met For non-DC-HSDPA services:

If the current cell does not support DC-HSDPA, the service requests access to the current cell preferentially. Go to step 5.

If the DC-HSDPA cell group is selected, the cell with the lightest load is selected. Go to step 5.

Condition 1 is not met Go to step 4.

4. The RNC selects a target cell for the UE to access.

The RNC determines whether any inter-frequency neighboring cell meets the following condition (condition 2):

For algorithm 1, condition 2 is as follows:

− For DCH services

(ThdAMR,nbcell - Pnon-H,nbcell) - (ThdAMR,cutcell - Pnon-H,cutcell) > ThdD,loadoffset

(Thdtotal,cutcell - Pload,cutcell) - (Thdtotal,nbcell - Pload,nbcell) < Thdtotal,loadoffset

Here,

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ThdAMR,nbcell is specified by DlConvAMRThd.

Pnon-H,nbcell is the ratio of the non-HSDPA power load of the neighboring cell to the total downlink load.

ThdD,loadoffset is specified by LdbDRDOffsetDCH.

Pload,cutcell is the ratio of the sum of the non-HSDPA power and the GBP load of the current cell to

the total downlink load.

Thdtotal,nbcell is specified by DlCellTotalThd.

Pload,nbcell is the ratio of the sum of the non-HSDPA power and the GBP load of the neighboring cell

to the total downlink load.

Thdtotal,loadoffset is specified by LdbDRDTotalPwrProThd.

For HSDPA services

(Thdtotal,nbcell - PGBP,nbcell) - (Thdtotal,cutcell - PGBP,cutcell) > ThdH,loadoffset

(Thdtotal,cutcell - Pload,cutcell) - (Thdtotal,nbcell - Pload,nbcell) < Thdtotal,loadoffset

Here,

PGBP,nbcell is the HS-DSCH GBP load of the neighboring cell.

ThdH,loadoffset is specified by LdbDRDOffsetHSDPA.

For algorithm 2, condition 2 is as follows:


(ThdAMR,nbcell – PD-enu,nbcell) - (ThdAMR,cutcell – PD-enu,cutcell) > ThdD,loadoffset

Here, PD-enu,nbcell is the ratio of the DCH ENU load of the neighboring cell to the total downlink ENU load.

− For HSDPA services

(ThdH-ue,nbcell – PH-ue,nbcell) / ThdH-ue,nbcell - (ThdH-ue,cutcell – PH-ue,cutcell) / ThdH-ue,cutcell > ThdH,loadoffset

Here,

ThdH-ue,nbcell is specified by MaxHsdpaUserNum.

PH-ue,nbcell is the total number of HSDPA users of the neighboring cell.

Then, the RNC selects the target cell as follows:

If there is only one inter-frequency neighboring cell that meets condition 2, the RNC selects this cell as the target cell. If there are multiple such cells:


a. If algorithm 1 is used, the RNC selects the cell with the lightest non-HSDPA load as the target cell.

b. If algorithm 2 is used, the RNC selects the cell with the lightest DCH ENU load as the target cell.

− For HSDPA services

a. If algorithm 1 is used, the RNC selects the cell with the lightest load of HS-DSCH required power as the target cell.

b. If algorithm 2 is used, the RNC selects the cell with the lightest HSDPA user load as the target cell.

If there no cell meets condition 2, the RNC selects the current cell as the target cell.


If the admission attempt is successful, the RNC admits the service request.

If the admission attempt fails, the RNC checks whether admission decisions have been made for all the candidate inter-frequency neighboring cells.


− If admission decisions have been made for all the candidate cells:


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a. When the service request is an HSPA one, the HSPA request falls back to a DCH one. Then, the algorithm goes back to step 1 to make an admission decision based on R99 service priorities.

b. When the service request is a DCH one, the RNC initiates an inter-RAT DRD.

For DC-HSDPA Services

If multiple DC-HSDPA cell groups are available after DRD for technological satisfaction and DRD for service steering, the RNC performs DRD for load balancing.

DRD for load balancing for DC-HSDPA services is similar to that of non-DC-HSDPA services. The difference is that the former considers cell groups (not individual cells), calculates their load factors, and finally selects a suitable cell group.

After the RNC selects a suitable DC-HSDPA cell group, it determines the primary cell based on the technological satisfaction and service priorities of the two cells. If the two cells have the same technological satisfaction and service priority, the RNC performs the following operations:

If the uplink load balancing switch ULLdbDRDSwitchDcHSDPA is turned off, the RNC selects either of the two cells as the primary cell.

If this switch is turned on, the RNC determines the primary cell based on uplink load balancing.

The uplink load balancing mechanism is introduced to prevent RNC from selecting the same cell as the primary cell for multiple UEs requesting DC-HSDPA services.

Uplink load balancing between the two cells is performed based on the uplink ENU.

During uplink load balancing, if the serving cell is not in the target DC-HSDPA cell group, the RNC selects a primary cell with a lighter load. Otherwise, the RNC checks whether the UL load margin of the serving cell is higher than the value of ULLdbDRDLoadRemainThdDCHSDPA:

If the margin is higher, the RNC selects the serving cell as the primary cell.

If the margin is not higher, the RNC calculates the difference between the UL load margin of the serving cell and that of the target cell. Then,

− If the difference is greater than the value of ULLdbDRDOffsetDcHSDPA, the RNC selects the target cell as the primary cell.

− Otherwise, the RNC selects the serving cell as the primary cell.

4.6.3 Code-Based DRD for Load Balancing

Code-based DRD for load balancing is similar to power-based DRD for load balancing. The difference is that the RNC considers code resources when selecting a target cell.

The following figure shows the procedure for code-based DRD for load balancing.

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Figure 4-5 Procedure for code-based DRD for load balancing

The procedure is as follows:

1. The RNC determines whether the minimum remaining SF of the current cell is smaller than the minimum SF threshold of DRD for code balancing (CodeBalancingDrdMinSFThd).

If the minimum SF is smaller than this threshold, the RNC requests access to the current cell.

If the minimum SF is not smaller than this threshold, the RNC goes to the next step.

2. The RNC determines whether the code load of the current cell is lower than the code occupation rate threshold of DRD for code balancing (CodeBalancingDrdCodeRateThd).

If the code load is lower than this threshold, the service tries to access the current cell.

If the code load is higher than or equal to this threshold, the RNC selects the cell as follows:

− If the minimum SF supported by the cell with the lightest code load is the same as that supported by the current cell, and the difference between the code resource occupancies of the two is greater than or equal to the value of DeltaCodeOccupiedRate, the RNC selects the cell with the lightest code load as the target cell. Otherwise, the RNC selects the current cell as the target cell.

− If the minimum SF supported by the cell with the lightest code load is smaller than the minimum SF supported by the current cell, the RNC selects the cell with the lightest code load as the target cell.

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4.7 Inter-RAT DRD

When all admission attempts for inter-frequency DRD during RAB processing fail, the RNC determines whether to initiate an inter-RAT DRD.

The following figure shows the inter-RAT DRD procedure.

Figure 4-6 Inter-RAT DRD procedure

The inter-RAT DRD procedure is as follows:

1. If the current cell is configured with any neighboring GSM cell suitable for blind handover and if the "service handover" IE in the RAB assignment signaling assigned by the CN is set to "handover to GSM should be performed" or "handover to GSM should not be performed," then the RNC performs step 2. Otherwise, the service request undergoes preemption and queuing.

Whether the neighboring cells support blind handover is specified by the parameter BlindHoFlag.

2. The RNC generates a list of candidate inter-RAT cells that support DRD and fulfill the quality requirement. For details, see 3 "RRC DRD." If the candidate cell list is empty, the service request undergoes preemption and queuing.

3. The RNC selects target GSM cells for the service request according to the blind handover priority. The blind handover priority of the cell is specified by the parameter BlindHOPrio.

4. If all admission attempts fail or the number of inter-RAT handover retries exceeds the value of DRMaxGSMNum, the service request undergoes preemption and queuing.

The inter-RAT DRD is not applicable to RABs of combined services, R99 PS services, and HSPA services.

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4.8 Measurement-Based Non-Periodic DRD

This section describes the feature WRFD-020402 measurement-based non-periodic DRD, or measurement-based direct retry (MBDR).

4.8.1 Overview

Measurement-based non-periodic DRD (MBDR) is a feature introduced in RAN12.0. It can increase the success rate of DRD, reduce the service drops caused by blind-handover-based non-periodic DRD. When an RAB is set up, the DRD algorithm uses a blind handover to achieve load balancing and service steering. If the current cell and the DRD target cell cover different areas, the UE DRD may fail. With the MBDR function, the success rate of inter-frequency or inter-RAT DRD can be ensured even if the current cell and the DRD target cell cover different areas. The UE access delay, however, is increased.

When an RRC connection is set up and MBDR is implemented, the RNC decides whether to establish the requested service in an inter-frequency or inter-RAT neighboring cell based on the current cell load and the type of service being established. If the RNC decides to establish the service in such a neighboring cell, the RNC sends an inter-frequency or inter-RAT measurement control message to the UE, instructing it to measure the signal quality of the neighboring cells. If the signal quality of a neighboring cell meets the requirements, the RNC establishes the service in that cell. Otherwise, the RNC attempts to establish the service in the current cell.

For a type of service, MBDR is controlled by the InterFreqActiveType and InterRatActiveType parameters.

Note that MBDR cannot be used simultaneously with blind-handover-based periodic DRD. When MBDR is enabled, blind-handover-based periodic DRD is automatically disabled.

4.8.2 MBDR Algorithm Switches

The MBDR algorithm switches are InterFreqActiveType and InterRatActiveType. They specify whether a certain service can use MBDR.

The following service types support inter-frequency MBDR:

− CS AMR

− CS non-AMR

− PS R99

− PS HSPA

Only CS AMR services support inter-RAT MBDR.

4.8.3 MBDR Procedure

Overview

The procedure for the inter-frequency MBDR algorithm is as follows:

1. After an RRC connection setup, the MBDR algorithm triggers the measurement of an inter-frequency MBDR cell if the corresponding MBDR algorithm switch is turned on and the current cell load exceeds the MBDR congestion decision threshold.

2. The RNC sends the UE an inter-frequency measurement control message, instructing the UE to measure the signal quality of the inter-frequency MBDR neighboring cells. If the signal quality of the inter-frequency MBDR cell meets the requirements, the RNC establishes services in this cell. If several inter-frequency MBDR cells qualify, the RNC prioritizes these cells and establishes services in the cell with the highest priority.

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3. If services are established successfully, the RAB is set up successfully. Otherwise, the RNC attempts to establish services in the cell with the second highest priority.

MBDR neighboring cells are specified by the MBDRFlag parameter.

The procedure for the inter-RAT MBDR algorithm is similar to that for the inter-frequency MBDR algorithm.

When the service type is CS AMR and the inter-frequency MBDR algorithm switch and inter-RAT MBDR algorithm switch are enabled, the UE selects the neighboring cell whose measurement report is received first. If the first received measurement report contains the inter-frequency cell information, the UE selects the inter-frequency cell as the target cell. If the first received measurement report contains inter-RAT cell information, the UE selects the inter-RAT cell as the target cell.

Triggering MBDR

After an RRC connection setup, if the MBDR algorithm is enabled for the service type to which this RAB belongs, the RNC triggers MBDR when either of the following conditions is met:

The uplink admission control switch NBMUlCacAlgoSelSwitch is not set to ALGORITHM_OFF, and the cell is in the MBDR congestion state. That is: Uplink admission threshold × MBDR congestion decision threshold ≤ Current cell load factor ≤ Uplink admission threshold

The downlink admission control switch NBMDlCacAlgoSelSwitch is not set to ALGORITHM_OFF, and the cell is in the MBDR congestion state. That is: Downlink admission threshold × MBDR congestion decision threshold ≤ Current cell load factor ≤ Downlink admission threshold

In the above two formulas:

The uplink admission threshold is specified by the UlNonCtrlThdForAMR, UlNonCtrlThdForNonAMR, or UlNonCtrlThdForOther parameter. The downlink admission threshold is specified by the DlConvAMRThd, DlConvNonAMRThd, or DlOtherThd parameter.

The MBDR congestion decision threshold is specified by the InterFreqUlMbdrTrigThreshold, InterFreqDlMbdrTrigThreshold, InterRatUlMbdrTrigThreshold, or InterRatDlMbdrTrigThreshold parameter.

The current cell load factor indicates the ratio of the used cell capacity to the total cell capacity. The current cell load factor for both the uplink and downlink is calculated by the RNC according to the cell load measurement results reported by NodeB. For details, see the Load Control Feature Parameter Description.

In the case of inter-RAT MBDR, the RNC triggers MBDR for only a certain percentage of UEs that meet the trigger conditions. This percentage is specified by the UserPercentage parameter.

MBDR Target Cell Selection

After MBDR is triggered, the RNC starts target cell selection.

If the current cell has only one MBDR neighboring cell, the RNC sends the UE a measurement request, instructing the UE to measure the signal quality of the neighboring cell. If the signal quality meets the requirements, the RNC establishes services in that cell. If service establishment fails, the RNC establishes services in the current cell.

If the current cell has more than one MBDR neighboring cell, the following procedure is triggered:

1. The RNC sends the UE a measurement request, instructing the UE to measure the signal quality of all the MBDR neighboring cells.

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2. According to the measurement results, the RNC selects the neighboring cells that meet the requirements as target cells. Note that a neighboring cell in the MBDR congestion state cannot be selected as a target cell.

− If only one neighboring cell meets the requirements, the RNC establishes services in this neighboring cell.

− If more than one neighboring cell meets the requirements, the RNC prioritizes these cells based on the value of the MBDRPrio parameter and then establishes services in the cell with the highest priority. If these cells have the same priority, the RNC randomly selects one of them and then establishes services in it. The smaller value of MBDRPrio, the higher its priority.

3. The RNC attempts to establish services in the neighboring cell with the highest priority. If the attempt fails, the RNC tries other neighboring cells in descending order of priority until the attempt succeeds or the number of attempts exceeds the value of the MaxAttNum parameter, in which case the RNC establishes services in the current cell.

Measurement Control Items

After MBDR is triggered, the RNC sends the UE a measurement control message, instructing the UE to measure the signal quality of the target cell. The UE reports the measurement results to the RNC.

The parameters associated with measurement control items, for example, the measurement report mode and trigger threshold, can be configured by running the ADD UCELLMBDRINTERFREQ or ADD UCELLMBDRINTERRAT command.

In the case of inter-frequency MBDR, you can:

Set the InterFreqReportMode parameter to PERIODICAL_REPORTING or EVENT_TRIGGER.

− With the setting PERIODICAL_REPORTING, the UE reports measurement results to the RNC at an interval specified by PrdReportInterval. Then, the RNC determines whether the signal quality of this inter-frequency cell meets the requirements according to the measurement results and the trigger conditions.

− With the setting EVENT_TRIGGER, the UE sends the RNC a measurement report (indicating that the signal quality of the inter-frequency cell meets the inter-frequency handover requirements) when the signal quality of the inter-frequency cell is higher than the trigger threshold for the period specified by TrigTime2C.

Set the InterFreqMeasQuantity parameter to Ec/No, RSCP, or BOTH.

− With the setting Ec/No, the Ec/No value of the target cell must reach the inter-frequency handover trigger threshold, which is specified by the HOThdEcN0 parameter.

− With the setting RSCP, the RSCP value of the target cell must reach the inter-frequency handover trigger threshold, which is specified by the HOThdRscp parameter.

− With the setting BOTH, both the Ec/No and RSCP values of the target cell must reach the corresponding inter-frequency handover trigger threshold.

Note:

The InterFreqMeasQuantity parameter cannot be set to BOTH if the InterFreqReportMode parameter is set to EVENT_TRIGGER.

In the case of inter-RAT MBDR, you can set the InterRatReportMode parameter to PERIODICAL_REPORTING or EVENT_TRIGGER.

With the setting PERIODICAL_REPORTING, the UE reports measurement results to the RNC at an interval specified by InterRATPeriodReportInterval. Then, the RNC compares the measurement results with InterRATHOThd to determine whether the signal quality of this inter-RAT cell meets the requirements.

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With the setting EVENT_TRIGGER, the UE sends the RNC a measurement report (indicating that the signal quality of the inter-RAT cell meets the inter-RAT handover requirements) when the signal quality of the inter-RAT cell is higher than the trigger threshold for the period specified by TrigTime3C.

The measurement mechanism for inter-frequency or inter-RAT MBDR is the same as that for handover. For details about the measurement mechanism, see the Handover Feature Parameter Description.

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Directed Retry Decision 5 Periodic DRD



5-1

5 Periodic DRD

5.1 Overview

5.1.1 Switches for Periodic DRD

The DR_RAB_SING_DRD_SWITCH and DR_RAB_COMB_DRD_SWITCH subparameters of the DrSwitch parameter determine whether to enable RAB DRD for a single service and a combined service, respectively. The BasedOnMeasHRetryDRDSwitch parameter further determines whether to enable blind-handover-based non-periodic DRD, blind-handover-based periodic DRD, or measurement-based periodic DRD.

When the subparameter DR_RAB_SING_DRD_SWITCH or DR_RAB_COMB_DRD_SWITCH is set to ON, the functions of the BasedOnMeasHRetryDRDSwitch parameter are as follows:

When the BasedOnMeasHRetryDRDSwitch parameter is set to ON:

− Measurement-based periodic DRD is enabled.

− Blind-handover-based periodic DRD is disabled.

− Blind-handover-based non-periodic DRD is controlled by the BlindDrdExceptHRetrySwitch parameter.

When the BasedOnMeasHRetryDRDSwitch parameter is set to OFF:

− Measurement-based periodic DRD is disabled.

− Blind-handover-based periodic DRD is enabled if the ChannelRetryTimerLen parameter is not set to 0.

− Blind-handover-based non-periodic DRD is enabled.

5.1.2 Triggering Periodic DRD

Periodic DRD is mainly triggered by the HSPA/HSPA+ retry. An HSPA/HSPA+ retry can be performed after a RAB setup or when the bearer scheme of a service is changed, for example, after RAB modification, a soft handover, hard handover, or cell change.

When the RAB is set up or the bearer scheme of a service is changed, the RNC determines whether the UE can be served by a better HSPA/HSPA+ technology by considering the technological satisfaction. If a better HSPA/HSPA+ technology can be used, the HSPA/HSPA+ retry is performed and consequently periodic DRD is triggered. In this way, a suitable cell can be selected to serve the UE with a better HSPA/HSPA+ technology.

If the parameter DPGDRDSwitch is set to ON, periodic DRD can also be triggered when a neighboring cell has a higher device type priority than the current cell, according to device type steering. If the parameter DPGDRDSwitch is set to OFF, device type priority is not considered during periodic DRD procedure. For details about device type priority, see the Intelligent Inter-Carrier Layered Management on UEs and Data Cards Feature Parameter Description.

Measurement-based periodic DRD can also be triggered when a neighboring cell has a higher service priority than the current cell, according to service steering.

In different situations, the HSPA/HSPA+ technologies that trigger HSPA/HSPA+ retry are different. The conditions under which an HSPA/HSPA+ technology can trigger HSPA/HSPA+ retry are as follows:

The HSPA+ technology is selected through RetryCapability parameter.

This condition does not apply to HSPA technologies.







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The HSPA/HSPA+ technology is supported by periodic DRD.

Note that different types of periodic DRD support different HSPA/HSPA+ technologies.

− Blind-handover-based periodic DRD supports the following HSPA/HSPA+ technologies: HSUPA, HSDPA, 64QAM, MIMO, DC-HSDPA, DC-HSDPA+MIMO, and E-DPCCH Boosting.

− Measurement-based periodic DRD supports the following HSPA/HSPA+ technologies: HSDPA, HSUPA, uplink enhanced L2, uplink 16QAM, downlink enhanced L2, CPC, 64QAM, DC-HSDPA, MIMO, DC-HSDPA+MIMO, and E-DPCCH Boosting.

When measurement-based periodic DRD is enabled, blind-handover-based non-periodic DRD cannot be applied. In such a case, the HSPA+ technologies supported by blind-handover-based non-periodic DRD are also supported by measurement-based periodic DRD. Therefore, blind-handover-based non-periodic DRD can be indirectly implemented through measurement-based periodic DRD.

When measurement-based periodic DRD is enabled, whether blind-handover-based non-periodic DRD can be applied is further determined by the BlindDrdExceptHRetrySwitch parameter. For details, see 4 "Non-Periodic DRD."

5.2 Periodic DRD Procedure

5.2.1 Blind-Handover-Based Periodic DRD

Blind-handover-based periodic DRD applies to the inter-frequency co-coverage scenarios. It is performed at regular intervals. The interval is specified by the ChannelRetryTimerLen parameter.

Figure 5-1 shows the procedure for blind-handover-based periodic DRD.

Figure 5-1 Procedure for blind-handover-based periodic DRD

The procedure for blind-handover-based periodic DRD is as follows:



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1. The RNC decides whether there are candidate cells that the UE can attempt to access. The candidate cells are selected from the co-coverage neighboring cells of the current best cell. A candidate cell must meet the following:


− The frequency of the cell is in the band supported by the UE.

− The cell supports the requested service.

− The cell is not overloaded.

− The technological satisfaction or device type priority of the cell is higher than that of the current cell.

If there are no such candidate cells, blind-handover-based periodic DRD fails, and the RNC waits for the next DRD period.

If there are any candidate cells, the following step is performed.

2. The RNC prioritizes the candidate cells according to device type and technological satisfaction.

3. The RNC attempts to access the target cell with the highest specifications for UE access.



If the admission attempt fails, the RNC removes the cell from the list of candidate cells and then checks whether all candidate cells have been tried.


− If none the candidate cells meet the requirements, blind-handover-based periodic DRD fails and the RNC waits for the next DRD period.

5.2.2 Measurement-Based Periodic DRD

In a multi-band network, cells that operate on different frequency bands have different coverage areas. When a UE needs to perform an inter-frequency handover in a multi-band network, it normally does not perform a blind handover, as the success rate of the blind handover is relatively low. Instead, the UE performs a handover decision according to the signal of each inter-frequency cell. Measurement-based periodic DRD is introduced to select a signal-qualified cell for the UE to access.

Measurement-based periodic DRD applies to both the inter-frequency same-coverage and the inter-frequency different-coverage scenarios and can increase the DRD success rate of both.

Figure 5-2 shows the procedure for measurement-based periodic DRD.


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Figure 5-2 Procedure for measurement-based periodic DRD

The procedure for measurement-based periodic DRD is as follows:

1. Based on technological satisfaction and cell service priority, the RNC decides whether there are candidate cells that the UE can attempt to access. The candidate cells are selected from the best cell and its neighboring cells.

A candidate cell must meet the following:

− The frequency of the cell is in the band supported by the UE.

− The cell supports the requested service.

− The DrdOrLdrFlag parameter of the cell is set to True, indicating that the cell can be measured.

− The technological satisfaction of the cell is higher than that of the current cell, or the service priority of the cell is higher than or equal to that of the current cell, or the device type priority of the cell is higher than that of current cell.

For details about the device type priority of the cell, see the Intelligent Inter-Carrier Layered Management on UEs and Data Cards Feature Parameter Description.

If there are any candidate cells, the following step is performed.

2. The RNC starts the timer for periodic DRD. The length of the timer is specified by the HRetryTimerLength parameter.

− If there is only one candidate cell and it is the current cell, the UE retries higher HSPA+ technologies in the current cell when the timer expires.

− Otherwise, the RNC issues a measurement control message, requesting the UE to measure the signal quality of all candidate cells.

3. The UE measures the RSCP and Ec/No of the candidate cells and periodically reports the measurement results to the RNC. The reporting period is specified by the PrdReportInterval parameter.

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4. Based on the received measurement results, the RNC selects the candidate target cells.

A candidate target cell must meet the following requirements:

− The cell is not overloaded.

− The measured RSCP is higher than the RSCP threshold specified by the TargetFreqThdRscp parameter.

− The measured Ec/No is higher than the Ec/No threshold specified by the TargetFreqThdEcN0 parameter.

If there are not candidate target cells, measurement-based periodic DRD fails. In such a case, the RNC waits for the DRD timer to expire.

If there are any candidate target cells, the following step is performed.

5. The RNC prioritizes the candidate target cells according to device type, technological satisfaction, and service priority.

6. The RNC attempts to access the target cell with the highest specifications for UE access.

7. The CAC algorithm makes an admission decision based on the status of the candidate target cell.


If the admission attempt fails, the RNC removes the cell from the list of candidate target cells and then checks whether all candidate target cells have been tried.


− If none of the candidate target cells meets the requirements, measurement-based periodic DRD fails and the RNC waits for the DRD timer to expire.

If the measurement or retry fails during measurement-based periodic DRD, a failure penalty timer starts when the DRD timer expires. During the penalty time, the preceding procedure cannot be performed and the UE can attempt to access only the current cell. The length of the penalty timer is specified by multiplying the value of the HRetryTimerLength parameter by the value of the DrdFaiPenaltyPeriodNum parameter.

../RNCParaHtml/mbsc/m-para/ucellmcdrd_targetfreqthdrscp.html

../RNCParaHtml/mbsc/m-para/ucellmcdrd_targetfreqthdecn0.html


../RNCParaHtml/mbsc/m-para/ucellmcdrd_drdfaipenaltyperiodnum.html

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Directed Retry Decision 6 Parameters



6-1

6 Parameters

Table 6-1 Parameter description

Parameter ID NE MML Command Description

BasedOnMeasHRetryDRDSwitch

BSC6900 SET UDRD(Optional) Meaning: Controls the validity of the measurement-based DRD algorithm. Assume that the DRD algorithm is enabled. If the switch is on, the RNC uses the DRD algorithm based on the measurement (for measuring the signals in the neighboring cell of the best cell). You can run the "SET UMCDRD" command to configure the related parameters. If the switch is off, the RNC implements the DRD algorithm based on blind handovers. Note: When the measurement-based DRD algorithm is used, you need to measure the signal quality of the target cell before a DRD retry. This cell can act as the actual target cell only when its signal quality meets the preset threshold. The measurement-based DRD is performed only for the periodic retry flow.

GUI Value Range: OFF, ON

Actual Value Range: OFF, ON

Default Value: OFF

BlindDrdExceptHRetrySwitch

BSC6900 ADD UCELLMCDRD(Optional)

MOD UCELLMCDRD(Optional)

Meaning: When the measurement-based DRD is performed, this parameter is used to determine whether the DRD retry for blind handover is performed in aperiodic mode. The aperiodic retry includes the setup of the RAB, modification of the RAB, and DCCC channel handover.

If this parameter is set to "ON", the DRD retry for blind handover is performed in aperiodic mode.

If this switch is set to "OFF", the DRD retry for blind handover is not performed in aperiodic mode.

GUI Value Range: OFF, ON

Actual Value Range: OFF, ON

Default Value: ON

BlindHOPrio BSC6900 ADD U2GNCELL(Mandatory)

MOD U2GNCELL(Mandatory)

Meaning: Priority of the neighboring cell for blind handover.

The value 0 represents the highest priority. Priorities 0 to 15 are assigned to concentric neighboring cells, which can ensure successful blind handover. Priorities 16 to 30 are assigned to the neighboring cells, which cannot ensure successful blind handover.

GUI Value Range: 0~30

Actual Value Range: 0~30

Default Value: None

BlindHoFlag BSC6900 ADD Meaning: Whether to perform blind handover.




../RNCParaHtml/mbsc/m-mml/set-udrd.html



../RNCParaHtml/mbsc/m-mml/add-ucellmcdrd.html



../RNCParaHtml/mbsc/m-mml/mod-ucellmcdrd.html




../RNCParaHtml/mbsc/m-mml/add-u2gncell.html



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UINTERFREQNCELL(Optional)

MOD UINTERFREQNCELL(Optional)

The value FALSE indicates that the cell is not considered as a candidate cell for blind handover. Therefore, blind over to this cell cannot be triggered.

GUI Value Range: FALSE, TRUE

Actual Value Range: FALSE, TRUE

Default Value: FALSE

BlindHoFlag BSC6900 ADD U2GNCELL(Optional)

MOD U2GNCELL(Optional)

Meaning: Whether to perform blind handover.

The value FALSE indicates that the cell is not considered as a candidate cell for blind handover. Therefore, blind over to this cell cannot be triggered.

GUI Value Range: FALSE, TRUE



ChannelRetryTimerLen

BSC6900 SET UCOIFTIMER(Optional)

Meaning: This parameter specifies the value of the channel retry timer. The timer will start when traffic is set up or reconfigured and some higher technique is not configured by some reason except for the capability of UE or cell. Channel retry will be performed after this timer expires.



Default Value: 5

CodeBalancingDrdCodeRateThd

BSC6900 ADD UCELLDRD(Optional)

MOD UCELLDRD(Optional)

Meaning: One of the triggering conditions of code balancing DRD. The other condition is the minimum spreading factor. Code balancing DRD is applied only when the code occupancy in the best cell is not lower than the value of this parameter.



Default Value: 13

CodeBalancingDrdMinSFThd



Meaning: One of the triggering conditions of code balancing DRD. The other condition is the code occupancy threshold. Code balancing DRD is applied only when the minimum spreading factor in the best cell is not lower than the value of this parameter.

GUI Value Range: SF4, SF8, SF16, SF32, SF64, SF128, SF256

Actual Value Range: SF4, SF8, SF16, SF32, SF64, SF128, SF256

Default Value: SF8

CodeBalancingDrdSwitch



Meaning: Whether to apply the code balancing DRD algorithm. The "DR_RAB_SING_DRD_SWITCH" parameter in "SET UCORRMALGOSWITCH" needs to be enabled. For combination services, the

../RNCParaHtml/mbsc/m-mml/mod-uinterfreqncell.html



../RNCParaHtml/mbsc/m-para/u2gncell_blindhoflag.html







../RNCParaHtml/mbsc/m-mml/set-ucoiftimer.html






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"DR_RAB_COMB_DRD_SWITCH" parameter needs to be enabled.

GUI Value Range: ON, OFF

Actual Value Range: ON, OFF

Default Value: OFF

DPGDRDSwitch



Meaning: The parameter specifies whether to enable the terminal type hierarchy algorithm.



Default Value: OFF

DRDEcN0Threshhold

BSC6900 ADD UINTERFREQNCELL(Optional)


Meaning: DRD Ec/No threshold for determining whether to perform the blind handover. If the measured Ec/No of the current cell is greater than this parameter, this cell can be the candidate cell for DRD.

GUI Value Range: -24~0

Actual Value Range: -24~0

Default Value: -18

DRMaxGSMNum



Meaning: Maximum number of inter-RAT RAB directed retries. It decides the size of the candidate set for inter-RAT DRD. The value 0 indicates that inter-RAT RAB DRD is not applicable. This parameter can be cell-oriented.



Default Value: 2

DeltaCodeOccupiedRate

BSC6900 SET UDRD(Optional) Meaning: Threshold of code occupancy offset between the current cell and the target cell when code balancing DRD is applied. Only when the cell code occupancy offset reaches this threshold can a neighboring cell be selected to be a candidate cell for DRD.



Default Value: 7

DlCellTotalThd BSC6900 ADD UCELLCAC(Optional)

MOD UCELLCAC(Optional)

Meaning: Admission threshold of the total cell downlink power. If the value is too high, too many users will be admitted. However, the throughput of a single user is easy to be limited. If the value is too low, cell capacity will be wasted.



Default Value: 90

























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DlConvAMRThd

BSC6900 ADD UCELLCAC(Optional)


Meaning: The percentage of the conversational AMR service threshold to the 100% downlink load. It is applicable to algorithm 1 and algorithm 2. The parameter is used for controlling the AMR service admission. That is, when an AMR service is accessing, the RNC evaluates the measurement value of the downlink load after the service is accessed. If the DL load of a cell is higher than this threshold after the access of an AMR speech service, this service will be rejected. If the DL load of a cell will not be higher than this threshold, this service will be admitted.

The DL load factor thresholds include parameters of [DL threshold of Conv non_AMR service], [DL handover access threshold] and [DL threshold of other services]. The four parameters can be used to limit the proportion between the conversational service, handover user and other services in a specific cell, and to guarantee the access priority of the conversational AMR service.



Default Value: 80

DlConvNonAMRThd



Meaning: The percentage of the conversational non-AMR service threshold to the 100% downlink load. It is applicable to algorithm 1 and algorithm 2. The parameter is used for controlling the non-AMR service admission. That is, when a non-AMR service is accessing, the RNC evaluates the measurement value of the downlink load after the service is accessed. If the DL load of a cell is higher than this threshold after the access of a non-AMR speech service, this service will be rejected. If the DL load of a cell will not be higher than this threshold, this service will be admitted.

The DL load factor thresholds include parameters of [DL threshold of Conv non_AMR service], [DL handover access threshold] and [DL threshold of other services]. The four parameters can be used to limit the proportion between the conversational service, handover user and other services in a specific cell, and to guarantee the access priority of the conversational non-AMR service.



Default Value: 80

DlOtherThd BSC6900 ADD UCELLCAC(Optional)

MOD

Meaning: The percentage of other service thresholds to the 100% downlink load. The services refer to other admissions except the conversational AMR













../RNCParaHtml/mbsc/m-para/ucellcac_dlotherthd.html




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UCELLCAC(Optional) service, conversational non-AMR service, and handover scenarios. It is applicable to algorithm 1 and algorithm 2. The parameter is used for controlling other service admissions. That is, when a service is accessing, the RNC evaluates the measurement value of the downlink load after the service is accessed. If the DL load of a cell is higher than this threshold after the access of a service, this service will be rejected. If the DL load of a cell will not be higher than this threshold, this service will be admitted.

The DL load factor thresholds include parameters of [DL threshold of Conv non_AMR service], [DL handover access threshold] and [DL threshold of other services]. The four parameters can be used to limit the proportion between the conversational service, handover user and other services in a specific cell, and to guarantee the access priority of other services.



Default Value: 75

DlTotalEqUserNum



Meaning: When the algorithm 2 is used, this parameter defines the total equivalent user number corresponding to the 100% downlink load. The parameter should be related to the admission threshold and actual condition of the network.



Default Value: 80

DrSwitch BSC6900 SET UCORRMALGOSWITCH(Optional)

Meaning: Direct retry switch group.

1) DR_RRC_DRD_SWITCH(DRD switch for RRC connection): When the switch is on, DRD and redirection is performed for RRC connection if retry is required.

2) DR_RAB_SING_DRD_SWITCH(DRD switch for single RAB): When the switch is on, DRD is performed for single service if retry is required.

3) DR_RAB_COMB_DRD_SWITCH(DRD switch for combine RAB): When the switch is on, DRD is performed for combined services if retry is required.

4) DR_INTER_RAT_DRD_SWITCH(INTER-RAT DRD switch): When this switch is turned on, inter-RAT directed retry is supported.

GUI Value Range: DR_RRC_DRD_SWITCH, DR_RAB_SING_DRD_SWITCH, DR_RAB_COMB_DRD_SWITCH, DR_INTER_RAT_DRD_SWITCH








../RNCParaHtml/mbsc/m-mml/set-ucorrmalgoswitch.html



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Actual Value Range: DR_RRC_DRD_SWITCH, DR_RAB_SING_DRD_SWITCH, DR_RAB_COMB_DRD_SWITCH, DR_INTER_RAT_DRD_SWITCH,

Default Value: None

DrdFaiPenaltyPeriodNum



Meaning: Number of retry periods in the interval between a failure of a measurement-based DRD re-attempt and the initiation of the next DRD re-attempt. If this parameter is set to a great value, the probability of a user re-accessing a cell with a high priority becomes low; If this parameter is set to a small value, the probability of a user re-accessing a cell with a high priority becomes high; however, the performance is greatly affected. Note: The process of a measurement-based DRD retry is as follows: At the beginning, the RNC determines to enable the DRD retry; then, it starts inter-frequency measurement control; next, the RNC receives the measurement report from a UE; after that, the RNC retries the access to a cell in the reported DRD cell list. The process ends until the cell access succeeds.



Default Value: 10

DrdOrLdrFlag BSC6900 ADD UINTERFREQNCELL(Optional)


Meaning: Specify the flags of the cells that the DRD measurement or LDR measurement is performed.

The value "TRUE" indicates that the cell can be considered as the measurement object in the DRD measurement algorithm or LDR measurement algorithm. The value "FALSE" indicates that the cell is invalid.

GUI Value Range: FALSE(Do not send), TRUE(Send)



HOThdEcN0 BSC6900 ADD UCELLMBDRINTERFREQ(Optional)

MOD UCELLMBDRINTERFREQ(Optional)

Meaning: Threshold of signal quality of the target frequency for triggering inter-frequency(Ec/No) measurement.

If the mode is set to event mode, this parameter is used to set measurement control on the event 2C.

If the mode is set to periodical mode, this parameter is used to estimate the periodical reports and only if quality of the target frequency is beyond the threshold, the DRD procedure is triggered.











../RNCParaHtml/mbsc/m-para/uinterfreqncell_drdorldrflag.html







../RNCParaHtml/mbsc/m-para/ucellmbdrinterfreq_hothdecn0.html

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Default Value: -16

HOThdRscp BSC6900 ADD UCELLMBDRINTERFREQ(Optional)


Meaning: Threshold of signal quality of the target frequency for triggering inter-frequency(RSCP) measurement.

If the mode is set to event mode, this parameter is used to set measurement control on the event 2C.

If the mode is set to periodical mode, this parameter is used to estimate the periodical reports and only if quality of the target frequency is beyond the threshold, the DRD procedure is triggered.

GUI Value Range: -115~-25

Actual Value Range: -115~-25

Default Value: -92

HRetryTimerLength



Meaning: Specifies the time length of the measurement-based DRD periodic retry timer. After the service is set up or the data reconfiguration is complete, and if the service data can be carried by the neighboring cell applied with an advanced technology or carried by the HCS cell with a higher priority, you need to enable the measurement-based DRD periodic retry timer, initiate an inter-frequency measurement for the DRD inter-frequency neighboring cell, and initiate the channel retry when the inter-frequency measurement report from the UE is received. When the timer expires, the channel retry can be initiated only in this cell. If this parameter is set to a greater value, the probability for subscribers to re-access the cell with a high priority becomes low. If this parameter is set to a smaller value, the probability for subscribers to re-access the cell with a high priority becomes high.



Default Value: 10

InterFreqActiveType

BSC6900 ADD UCELLMBDRINTERFREQ(Optional)


Meaning: MBDR switch

GUI Value Range: CSAMR_INTERFREQ(CS AMR inter-frequency switch), CSNONAMR_INTERFREQ(CS non AMR inter-frequency switch), PSR99_INTERFREQ(PSR99 inter-frequency switch), PSHSPA_INTERFREQ(PSHSPA inter-frequency switch)

Actual Value Range: CSAMR_INTERFREQ, CSNONAMR_INTERFREQ, PSR99_INTERFREQ, PSHSPA_INTERFREQ

Default Value: None

../RNCParaHtml/mbsc/m-para/ucellmbdrinterfreq_hothdrscp.html























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InterFreqDlMbdrTrigThreshold



Meaning: This parameter is the relative threshold of cell for judging whether downlink MBDR algorithm of inter frequency is in overload state. It represents the percentage of the cell admission control threshold of downlink. The smaller this parameter is, the earlier downlink MBDR algorithm of inter frequency goes into overload state. When cell load is higher than the product of downlink cell admission control threshold and this parameter, and is lower than the downlink cell admission control threshold, downlink MBDR algorithm of inter frequency is in overload state.



Default Value: 80

InterFreqMeasQuantity



Meaning: Measurement quantity used in measurement-based inter-frequency measurement in event (2C) triggered or periodical reporting mode.

- CPICH: Common Pilot Channel

- Ec/No: Signal-to-Noise Ratio

- RSCP: Received Signal Code Power

- CPICH_Ec/No: to use the Ec/No measurement quantity for event 2C or Inter-Frequency periodical measurement. The physical unit is dB.

- CPICH_RSCP: to use the RSCP measurement quantity for event 2C or Inter-Frequency periodical measurement. The physical unit is dBm.

- BOTH:both quantities of the target cell must be satisfied when performing the handover judgement.Valid when the Inter-Frequency measurement chooses PERIODICAL_REPORTING Mode. Recommended value (default value): BOTH(PERIODICAL_REPORTING Mode), CPICH_RSCP(EVENT_TRIGGER Mode)

GUI Value Range: CPICH_EC/NO, CPICH_RSCP, BOTH

Actual Value Range: CPICH_EC/NO, CPICH_RSCP, BOTH

Default Value: CPICH_EC/NO

InterFreqReportMode



Meaning: Inter-frequency measurement report mode.

If this parameter is set to PERIODICAL_REPORTING, measurement reports are periodically reported. If this parameter is set to EVENT_TRIGGER, measurement reports are reported by triggering the event.

There are two inter-frequency handover report modes in the RNC, namely, event-triggered report and periodical report.


























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- Event-triggered measurement report

In this mode, event 2C is used to decide whether to trigger inter-frequency handover.

- Periodical report mode

When the quality of the inter-frequency cell reported by the UE meets the criteria for inter-frequency handover, the delay trigger timer is started. If the quality of the cell always meets the criteria for inter-frequency handover before timeout, the inter-frequency handover is triggered after the delay trigger timer expires.

GUI Value Range: PERIODICAL_REPORTING(Periodical reporting), EVENT_TRIGGER(Event trigger)

Actual Value Range: PERIODICAL_REPORTING, EVENT_TRIGGER

Default Value: EVENT_TRIGGER

InterFreqUlMbdrTrigThreshold



Meaning: This parameter is the relative threshold of cell for judging whether uplink MBDR algorithm of inter frequency is in overload state. It represents the percentage of the cell admission control threshold of uplink. The smaller this parameter is, the earlier uplink MBDR algorithm of inter frequency goes into overload state. When cell load is higher than the product of uplink cell admission control threshold and this parameter, and is lower than the uplink cell admission control threshold, uplink MBDR algorithm of inter frequency is in overload state.



Default Value: 80

InterRATHOThd

BSC6900 ADD UCELLMBDRINTERRAT(Optional)

MOD UCELLMBDRINTERRAT(Optional)

Meaning: Quality requirement for the inter-RAT cell during an inter-RAT handover with CS domain services.

This parameter is used to set measurement control on the event 3C. The event 3C is triggered when the signal quality of the target frequency is above this threshold. Note that the value 0 indicates that the physical value is smaller than -110 dBm.

If the periodical report mode is used, the inter-RAT handover decision thresholds are used for the assessment of inter-RAT coverage handover, namely as Tother_RAT in the following formulas. The inter-RAT handover decision thresholds are the absolute thresholds (RSSI) of inter-RAT cell quality for the inter-RAT handover decision.

If the quality of another RAT in the inter-RAT measurement report meets the following condition:












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Mother_RAT + CIO >= Tother_RAT + H/2

the system starts the trigger timer and implements the handover decision after timeout. If the quality of the preceding RAT meets the following condition before timeout:

Mother_RAT + CIO < Tother_RAT - H/2

The system stops the timer, and the RNC waits for another inter-RAT measurement report.

In which,

Mother_RAT indicates the measurement result of the GSM RSSI;

Tother_RAT indicates the inter-RAT handover decision threshold;

Cell Individual Offset (CIO) indicates the offset of the inter-RAT cell;

H represents the hysteresis. Hysteresis can reduce wrong decisions caused by signal jitters.

The sensitivity of a GSM mobile phone is -102 dBm, so the outdoor reception level should not be lower than -90 dBm, considering a margin of 3 dB for compensation of fast fading, 5 dB for compensation of slow fading, 2 dB for compensation of interference noise, and 2 dB for compensation of ambient noise.

The values of inter-RAT handover decision thresholds vary with the handover policy. To have UEs hand over only to the GSM cells with high quality, you can set the inter-RAT handover decision threshold to a comparatively high value, for example -85 dBm.


Actual Value Range: lower than -110, -110~-48(Actual value meets the condition: Actual Value = GUI Value - 111)

Default Value: 21

InterRATPeriodReportInterval



Meaning: Interval that the UE reports inter-RAT measurement results to the RNC.

This parameter specifies the interval that the UE sends inter-RAT measurement results to the RNC in periodical reporting mode. It is not recommended that this parameter is set to NON_PERIODIC_REPORT since the UE behavior may be unknown.

The GSM RSSI measurement period is 480 ms. Therefore, the inter-RAT periodical reporting interval should be longer than 480 ms. If the periodical reporting interval is excessively high, the handover decision time will be long, and handovers will be slow.










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The adjustment should be made according to the configured GSM RSSI measurement compressed mode sequence. According to the current configured GSM RSSI measurement compressed mode sequence, the RSSI measurement of eight GSM cells can be finished in 480 ms. Therefore, the RSSI measurement of 16 GSM cells can be finished in 1000 ms. According to 3GPP specifications, the number of inter-RAT neighboring cells should not exceed 32. Therefore, the parameter value can be set to 2000 ms if the number of neighboring GSM cells exceeds 16.

The setting of this parameter has impact on the Uu signaling traffic. If the period is too short and the reporting frequency is too high, the RNC may have high load in processing signaling. If the period is too long, the network cannot detect the signal changes in time, which may delay the inter-RAT handover and thus cause call drops.

GUI Value Range: NON_PERIODIC_REPORT(Non periodical reporting), D250(D250), D500(D500), D1000(D1000), D2000(D2000), D3000(D3000), D4000(D4000), D6000(D6000), D8000(D8000), D12000(D12000), D16000(D16000), D20000(D20000), D24000(D24000), D28000(D28000), D32000(D32000), D64000(D64000)

Actual Value Range: NON_PERIODIC_REPORT, 250, 500, 1000, 2000, 3000, 4000, 6000, 8000, 12000, 16000, 20000, 24000, 28000, 32000, 64000

Default Value: D1000

InterRatActiveType



Meaning: MBDR switch

GUI Value Range: CSAMR_INTERRAT(CS AMR inter-RAT switch)

Actual Value Range: CSAMR_INTERRAT

Default Value: None

InterRatDlMbdrTrigThreshold



Meaning: This parameter is the relative threshold of cell for judging whether downlink MBDR algorithm of inter RAT is in overload state. It represents the percentage of the cell admission control threshold of downlink. The smaller this parameter is, the earlier downlink MBDR algorithm of inter RAT goes into overload state. When cell load is higher than the product of downlink cell admission control threshold and this parameter, and is lower than the downlink cell admission control threshold, downlink MBDR algorithm of inter RAT is in overload state.


















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Default Value: 80

InterRatReportMode



Meaning: Inter-RAT measurement report mode.

When PERIODICAL_REPORTING is selected, the periodical reporting is used for inter-RAT measurement. When EVENT_TRIGGER is selected, the event-triggered reporting is used for inter-RAT measurement.

The RNC provides two inter-RAT measurement reporting modes, event-triggered reporting and periodical reporting.

-Event-triggered measurement report

In this mode, event 3C is used to decide whether to trigger inter-RAT handover.

-Periodical report mode

When the quality of the GSM cell reported by the UE meets the criteria for inter-RAT handover, the delay trigger timer is started. If the quality of the GSM cell always meets the criteria for inter-RAT handover before timeout, the inter-RAT handover is triggered after the delay trigger timer expires.

For the GSM cell whose BSIC can be decoded correctly, a shorter delay trigger time should be set to indicate the high priority attribute of the GSM cell. For the GSM cell whose BSIC is not verified, a longer delay trigger time should be set to indicate the low priority attribute of the GSM cell. In this manner, the BSIC can be decoded faster.

GUI Value Range: PERIODICAL_REPORTING(Periodical reporting), EVENT_TRIGGER(Event trigger)

Actual Value Range: PERIODICAL_REPORTING, EVENT_TRIGGER

Default Value: EVENT_TRIGGER

InterRatUlMbdrTrigThreshold



Meaning: This parameter is the relative threshold of cell for judging whether uplink MBDR algorithm of inter RAT is in overload state. It represents the percentage of the cell admission control threshold of uplink. The smaller this parameter is, the earlier uplink MBDR algorithm of inter RAT goes into overload state. When cell load is higher than the product of uplink cell admission control threshold and this parameter, and is lower than the uplink cell admission control threshold, uplink MBDR algorithm of inter RAT is in overload state.



















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Default Value: 80

LdbDRDLoadRemainThdDCH



Meaning: Downlink load threshold to trigger load balancing DRD for DCH services. The load balancing DRD will be triggered only when the downlink remnant non-H power or remnant R99 equivalent user number of the cell is less than this threshold.



Default Value: 35

LdbDRDLoadRemainThdHSDPA



Meaning: Downlink load threshold to trigger load balancing DRD for HSDPA services. The load balancing DRD will probably be triggered only when the downlink remnant HSDPA guarantee power or remnant HSDPA user number of the cell is less than this threshold.



Default Value: 100

LdbDRDOffsetDCH

BSC6900 SET UDRD(Optional) Meaning: Threshold of remnant load offset between the current cell and the target cell when load balancing DRD is applied to DCH users. Only when the remnant load offset reaches this threshold can a neighboring cell be selected as a candidate DRD cell for DCH users. If "Load Balancing DRD Choice" is set to Power, additional condition should also be satisfied, that is, total power remnant difference between the current cell and target cell must be less than "Load Balance DRD Total Power Protect Threshold"; if "Load Balancing DRD Choice" is set to UserNumber, additional condition is not needed.



Default Value: 10

LdbDRDOffsetHSDPA

BSC6900 SET UDRD(Optional) Meaning: Threshold of remnant load offset between the current cell and the target cell when load balancing DRD is applied to HSDPA users. Only when the remnant load offset reaches this threshold can a neighboring cell be selected as a candidate DRD cell for HSDPA users. If "Load Balancing DRD Choice" is set to Power, additional condition should also be satisfied, that is, total power remnant difference between the current cell and target cell must be less than "Load Balance DRD Total Power Protect Threshold"; if "Load Balancing DRD Choice" is set to UserNumber, additional condition is not needed.






















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Default Value: 10

LdbDRDSwitchDCH



Meaning: Whether the load balancing DRD algorithm is applied to DCH services.

- ON: The load balancing DRD algorithm will be applied.

- OFF: The load balancing DRD algorithm will not be applied.



Default Value: OFF

LdbDRDSwitchHSDPA



Meaning: Whether the load balancing DRD algorithm is applied to HSDPA services.

- ON: The load balancing DRD algorithm will be applied.

- OFF: The load balancing DRD algorithm will not be applied.



Default Value: OFF

LdbDRDTotalPwrProThd

BSC6900 SET UDRD(Optional) Meaning: Threshold of the total downlink remnant power difference between the current cell and the target cell when load balancing DRD is applied and the "Load Balancing DRD Choice" parameter is set to Power. Only when the total downlink remnant power difference is less than this threshold can a neighboring cell be selected as a candidate DRD cell. The other condition is that remnant load offset reaches the threshold defined by the parameter of "Load Balance DRD Offset for DCH" or "Load Balance DRD Offset for HSDPA".



Default Value: 30

LdbDRDchoice



Meaning: Whether load balancing DRD is based on power or on user number.

- Power: Power(Downlink none-HSDPA power is used for DCH services, and downlink HSDPA guarantee power is used for HSDPA services) will be applied to the load balancing DRD algorithm.

- UserNumber: User number(Downlink R99 equivalent user number is used for DCH services, and downlink HSDPA user number is used for HSDPA services) will be applied to the load balancing DRD algorithm.






















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GUI Value Range: Power, UserNumber

Actual Value Range: Power, UserNumber

Default Value: UserNumber

MBDRFlag BSC6900 ADD UINTERFREQNCELL(Optional)


Meaning: Whether the cell supports the measure-based directed retry (MBDR) algorithm.

The value TRUE indicates that the cell supports the MBDR algorithm, and the value FALSE indicates that the cell does not support the MBDR algorithm.

GUI Value Range: FALSE(Do not send), TRUE(Send)



MBDRPrio BSC6900 ADD UINTERFREQNCELL(Optional)


Meaning: Priority of a MBDR cell.

This parameter is valid only when the "MBDRFlag" parameter is set to TRUE. It indicates the tiptop priority when the value is set to 0, and the lowest priority when the value is set to 15. The higher the priority, the easier it is for the MBDR cell to be delivered as the measurement object and the easier to be selected to the handover target cell when there are many of cells meet the quality condition. Attention, when there does not have cell meet the quality condition base on the MBDR measurement result, if there exists a cell which has the priority of 0, and the type of the measurement report is periodic, then it can be selected to blind handover target cell.



Default Value: 0

MIMO64QAMorDCHSDPASwitch

BSC6900 SET UFRC(Optional) Meaning: This switch is used to configure the priority of MIMO_64QAM or DC-HSDPA. According to different protocols, the following situations may occur: MIMO and DC-HSDPA cannot be used together; both 64QAM and DC-HSDPA are supported, but cannot be used together. In this case, "MIMO64QAMorDCHSDPASwitch" is used to configure the priorities of the features. When the priority of MIMO is higher than that of DC-HSDPA, the priority of 64QAM is higher than that of DC-HSDPA. When the priority of DC-HSDPA is higher than that of MIMO, the priority of DC-HSDPA is higher than that of 64QAM.

GUI Value Range: MIMO_64QAM, DC_HSDPA

Actual Value Range: MIMO_64QAM, DC_HSDPA

Default Value: DC_HSDPA

MIMOor64QA BSC6900 SET UFRC(Optional) Meaning: According to the R8 protocol, MIMO and

../RNCParaHtml/mbsc/m-para/uinterfreqncell_mbdrflag.html

















../RNCParaHtml/mbsc/m-mml/set-ufrc.html



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MSwitch 64QAM can be used together. When the condition is not met, for example the cell does not support the features, MIMO may be not used together with 64QAM. In this case, "MIMOor64QAMSwitch" is used to determine whether MIMO or 64QAM is preferentially used.

GUI Value Range: MIMO, 64QAM

Actual Value Range: MIMO, 64QAM

Default Value: MIMO

MaxAttNum BSC6900 ADD UCELLMBDRINTERFREQ(Optional)


Meaning: The maximum number of attempts to perform inter-freq handovers

This parameter specifies the maximum number of attempts for the RNC to perform inter-freq handover after inter-freq handover failure. The handover attempts should involve the cells that have not been tried but satisfy the handover conditions.



Default Value: 1

MaxHsdpaUserNum



Meaning: Maximum number of users supported by the HSDPA channel. The user in this parameter refers to the user with services on the HSDPA channel, regardless of the number of RABs carried on the HSDPA channel. Maximum HSDPA user number cannot exceed the HSDPA capability of the NodeB product, In practice, the value can be set based on the cell type and the richness of the available HSDPA power and code resources.



Default Value: 64

NBMDlCacAlgoSelSwitch

BSC6900 ADD UCELLALGOSWITCH(Mandatory)

MOD UCELLALGOSWITCH(Optional)

Meaning: The algorithms with the above values represent are as follow:

ALGORITHM_OFF: Disable downlink call admission control algorithm.

ALGORITHM_FIRST: The load factor prediction algorithm will be used in downlink CAC.

ALGORITHM_SECOND: The equivalent user number algorithm will be used in downlink CAC.

ALGORITHM_THIRD: The loose call admission control algorithm will be used in downlink CAC.

GUI Value Range: ALGORITHM_OFF, ALGORITHM_FIRST, ALGORITHM_SECOND, ALGORITHM_THIRD

Actual Value Range: ALGORITHM_OFF, ALGORITHM_FIRST, ALGORITHM_SECOND,

../RNCParaHtml/mbsc/m-para/ucellmbdrinterfreq_maxattnum.html















../RNCParaHtml/mbsc/m-mml/add-ucellalgoswitch.html



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ALGORITHM_THIRD

Default Value: None

NBMUlCacAlgoSelSwitch

BSC6900 ADD UCELLALGOSWITCH(Mandatory)

MOD UCELLALGOSWITCH(Optional)

Meaning: The algorithms with the above values represent are as follow:

ALGORITHM_OFF: Disable uplink call admission control algorithm.

ALGORITHM_FIRST: The load factor prediction algorithm will be used in uplink CAC.

ALGORITHM_SECOND: The equivalent user number algorithm will be used in uplink CAC.

ALGORITHM_THIRD: The loose call admission control algorithm will be used in uplink CAC.

GUI Value Range: ALGORITHM_OFF, ALGORITHM_FIRST, ALGORITHM_SECOND, ALGORITHM_THIRD

Actual Value Range: ALGORITHM_OFF, ALGORITHM_FIRST, ALGORITHM_SECOND, ALGORITHM_THIRD

Default Value: None

PrdReportInterval



Meaning: Interval between periodic reporting for the inter-frequency handover.

In periodic reporting mode, the inter-frequency handover attempts is reported at the preset interval. It is not recommended that this parameter be set to "NON_PERIODIC_REPORT" since the UE behavior may be unknown. This parameter has impact on the Uu signaling flow. If the interval is too short and the frequency is too high, the RNC may have high load when processing signaling. If the interval is too long, the network cannot detect the signal changes in time. This may delay the inter-frequency handover, thus causing call drops.

GUI Value Range: NON_PERIODIC_REPORT(Non periodical reporting), D250(D250), D500(D500), D1000(D1000), D2000(D2000), D3000(D3000), D4000(D4000), D6000(D6000), D8000(D8000), D12000(D12000), D16000(D16000), D20000(D20000), D24000(D24000), D28000(D28000), D32000(D32000), D64000(D64000)

Actual Value Range: NON_PERIODIC_REPORT, 250, 500, 1000, 2000, 3000, 4000, 6000, 8000, 12000, 16000, 20000, 24000, 28000, 32000, 64000

Default Value: D500

RetryCapability

BSC6900 SET UFRC(Optional) Meaning: This parameter specifies which HSPA technologies can be retried by UEs. When the HSPA technologies are selected and currently UE is not




















WCDMA RAN




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using them, RNC will initiate these HSPA technologies retry for UE.

GUI Value Range: SRB_OVER_HSDPA, SRB_OVER_HSUPA, TTI_2MS, MIMO, 64QAM, DL_L2_ENHANCE, DTX_DRX, HSSCCH_LESS_OPERATION, MIMO_64QAM, DC_HSDPA, UL_L2_ENHANCE, UL_16QAM, EDPCCH_BOOSTING, DCMIMO_HSDPA

Actual Value Range: SRB_OVER_HSDPA, SRB_OVER_HSUPA, TTI_2MS, MIMO, 64QAM, DL_L2_ENHANCE, DTX_DRX, HSSCCH_LESS_OPERATION, MIMO_64QAM, DC_HSDPA, UL_L2_ENHANCE, UL_16QAM, EDPCCH_BOOSTING, DCMIMO_HSDPA

Default Value: None

ServiceDiffDrdSwitch



Meaning: Whether the service steering DRD algorithm is applied.



Default Value: OFF

SpgId BSC6900 ADD USPG(Mandatory)

MOD USPG(Mandatory)

RMV USPG(Mandatory)

Meaning: Identifies a group of cells that have specific capabilities for different service types. You can take any value that is not in use. The used values can be queried through the "LST USPG" command.



Default Value: None

TargetFreqThdEcN0



Meaning: Ec/No Threshold for the target cell. This parameter is used to estimate the signal quality of the periodic reports. The DRD is triggered only when the signal quality of the target cell is higher than this parameter. If this parameter is set to a greater value, it is difficult for subscribers to re-access another cell with a higher priority; however, the re-attempt success rate is high. If this parameter is set to a lower value, it is easy for subscribers to re-access another cell with a higher priority; however, the re-attempt success rate however is low. Note: The threshold can be reached only when RSCP and Ec/No of the target cell are above the RSCP and EcNo that are set in the command.In order to increase the successful rate of handover, inner protection mechanism keep Ec/No of target cell larger than -16.



Default Value: -12







../RNCParaHtml/mbsc/m-para/uspg_spgid.html

../RNCParaHtml/mbsc/m-mml/add-uspg.html

../RNCParaHtml/mbsc/m-mml/add-uspg.html

../RNCParaHtml/mbsc/m-mml/mod-uspg.html

../RNCParaHtml/mbsc/m-mml/mod-uspg.html

../RNCParaHtml/mbsc/m-mml/rmv-uspg.html

../RNCParaHtml/mbsc/m-mml/rmv-uspg.html









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TargetFreqThdRscp



Meaning: RSCP Threshold for the target cell. This parameter is used to estimate the signal quality of the periodic reports.The DRD is triggered only when the signal quality of the target cell is higher than this parameter. If this parameter is set to a greater value, it is difficult for subscribers to re-access another cell with a higher priority; however, the re-attempt success rate is high. If this parameter is set to a lower value, it is easy for subscribers to re-access another cell with a higher priority; however, the re-attempt success rate however is low. Note: The threshold can be reached only when RSCP and Ec/No of the target cell are above the RSCP and Ec/No that are set in the command.

GUI Value Range: -115~-25

Actual Value Range: -115~-25

Default Value: -92

TrigTime2C BSC6900 ADD UCELLMBDRINTERFREQ(Optional)


Meaning: Interval time between detection of event 2C and sending of the measurement report.

The value of this parameter is associated with slow fading. If this parameter is set to a greater value, the probability of incorrect decision becomes low; however, the handover algorithm becomes slow in responding to signal change.

The emulation results show that setting this interval can effectively reduce the average number of handovers and the number of incorrect handovers, preventing unnecessary handovers. In addition, the UE at different rates may react differently to the same interval. For the fast-moving UE, the call drop rate is more sensitive to this interval, whereas, for the slow-moving UE, the call drop rate is less sensitive to this interval. Therefore, for the cell with most of the fast-moving UEs, this parameter can be set to a smaller value, whereas for the cell with most of the slow-moving UEs, this parameter can be set to a greater value. The value of this parameter can be adjusted according to the actual network statistics.

GUI Value Range: D0, D10, D20, D40, D60, D80, D100, D120, D160, D200, D240, D320, D640, D1280, D2560, D5000

Actual Value Range: 0, 10, 20, 40, 60, 80, 100, 120, 160, 200, 240, 320, 640, 1280, 2560, 5000

Default Value: D640

TrigTime3C BSC6900 ADD UCELLMBDRINTERRAT(Optional)

MOD UCELLMBDRINTERR

Meaning: Interval time between detection of event 3C and sending of the measurement report.

The value of this parameter is associated with the slow fading. If this parameter is set to a greater value, the probability of incorrect handover decision









../RNCParaHtml/mbsc/m-para/ucellmbdrinterfreq_trigtime2c.html







../RNCParaHtml/mbsc/m-para/ucellmbdrinterrat_trigtime3c.html






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AT(Optional) becomes low; however, the handover algorithm becomes slow in responding to signal change. If this parameter is set to a smaller value, the handover algorithm becomes fast in responding to signal change; however, the probability of incorrect decision becomes high.

The emulation result shows that the hysteresis setting can effectively reduce the average number of handovers and the number of incorrect handovers, thus preventing unnecessary handovers. The emulation result also shows that the UE at different data rates may react differently to the delay for triggering the event. For the fast-moving UE, the call drop rate is more sensitive to the delay, whereas, for the slow-moving UE, the call drop rate is less sensitive to the delay. This can also reduce ping-pong handovers and incorrect handovers. Therefore, for the cell where most UEs are in fast movement, this parameter can be set to a smaller value, whereas for the cell where most UEs are in slow movement, this parameter can be set to a greater value. The value of this parameter can be adjusted according to the actual network statistics.

The inter-frequency measurement reporting period is 480 ms. Therefore, the trigger delay time shorter than 480 ms is invalid.

If the parameter is set to a larger value, handover is unlikely to be triggered. However, call drops may increase as the parameter value increases.

GUI Value Range: D0, D10, D20, D40, D60, D80, D100, D120, D160, D200, D240, D320, D640, D1280, D2560, D5000

Actual Value Range: 0, 10, 20, 40, 60, 80, 100, 120, 160, 200, 240, 320, 640, 1280, 2560, 5000

Default Value: D640

ULLdbDRDLoadRemainThdDcHSDPA



Meaning: This parameter specifies the threshold of triggering the uplink load balance for DC-HSDPA traffic. If the remaining number of equivalent users in the uplink is less than the value of this parameter, uplink load balance for DC-HSDPA traffic is triggered.



Default Value: 25

ULLdbDRDOffsetDcHSDPA

BSC6900 SET UDRD(Optional) Meaning: If the difference of the remaining number of equivalent users in the uplink between the target cell and the serving cell is greater than the value of this parameter, the target cell meets one of the qualifications to be the candidate cell for directed retry.











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Default Value: 10

ULLdbDRDSwitchDcHSDPA



Meaning: This parameter specifies whether to enable the uplink load balance for DC-HSDPA traffic. The uplink load balance is performed on the basis of the equivalent number of users.



Default Value: OFF

UlNonCtrlThdForAMR



Meaning: The percentage of the conversational non-AMR service threshold to the 100% uplink load. It is applicable to algorithm 1 and algorithm 2. The parameter is used for controlling the non-AMR service admission. That is, when a non-AMR service is accessing, the RNC evaluates the measurement value of the uplink load after the service is accessed. If the UL load of a cell is higher than this threshold after the access of a non-AMR speech service, this service will be rejected. If the UL load of a cell will not be higher than this threshold, this service will be admitted.

The UL load factor thresholds include parameters of [UL threshold of Conv non_AMR service], [UL handover access threshold] and [UL threshold of other services]. The four parameters can be used to limit the proportion between the conversational service, handover user and other services in a specific cell, and to guarantee the access priority of the conversational non-AMR service.



Default Value: 75

UlNonCtrlThdForNonAMR



Meaning: The percentage of the conversational non-AMR service threshold to the 100% uplink load. It is applicable to algorithm 1 and algorithm 2. The parameter is used for controlling the non-AMR service admission. That is, when a non-AMR service is accessing, the RNC evaluates the measurement value of the uplink load after the service is accessed. If the UL load of a cell is higher than this threshold after the access of a non-AMR speech service, this service will be rejected. If the UL load of a cell will not be higher than this threshold, this service will be admitted.

The UL load factor thresholds include parameters of [UL threshold of Conv non_AMR service], [UL handover access threshold] and [UL threshold of



















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6-22


other services]. The four parameters can be used to limit the proportion between the conversational service, handover user and other services in a specific cell, and to guarantee the access priority of the conversational non-AMR service.



Default Value: 75

UlNonCtrlThdForOther



Meaning: The percentage of other service thresholds to the 100% uplink load. The services refer to other admissions except the conversational AMR service, conversational non-AMR service, and handover scenarios. It is applicable to algorithm 1 and algorithm 2. The parameter is used for controlling other service admissions. That is, when a service is accessing, the RNC evaluates the measurement value of the uplink load after the service is accessed. If the UL load of a cell is higher than this threshold after the access of a service, this service will be rejected. If the UL load of a cell will not be higher than this threshold, this service will be admitted.

The UL load factor thresholds include parameters of [UL threshold of Conv non_AMR service], [UL handover access threshold] and [UL threshold of other services]. The four parameters can be used to limit the proportion between the conversational service, handover user and other services in a specific cell, and to guarantee the access priority of other services.



Default Value: 60

UserPercentage



Meaning: The ratio of the users which could launch the handover to inter-RAT neighbour cell.

When the parameter is ALL_USER, it means all of the users could be handover to the inter-RAT neighbour cell. When the parameter is HALF, it means only 1/2 of the users could be handover to the inter-RAT neighbour cell. When the parameter is THIRD, it means only 1/3 of the users could be handover to the inter-RAT neighbour cell. When the parameter is QUARTER, it means only 1/4 of the users could be handover to the inter-RAT neighbour cell.

GUI Value Range: ALL_USER(All User), HALF(Half), THIRD(THIRD), QUARTER(QUARTER)

Actual Value Range: ALL_USER, HALF, THIRD, QUARTER















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Default Value: ALL_USER

WCDMA RAN

Directed Retry Decision 7 Counters



7-1

7 Counters

Table 7-1 Counter description

Counter ID

Counter Name Counter Description

Feature ID Feature Name

67189400 VS.RRC.Estab.DRDOut.Att Number of RRC Connection Setup Attempts with DRD out for Cell


67189401 VS.RRC.Estab.DRDOut.Succ Number of Successful RRC Connection Setups with DRD out for Cell

WRFD-02040001

WRFD-010510

Intra System Direct Retry

3.4/6.8/13.6/27.2Kbps RRC Connection and Radio Access Bearer Establishment and Release

67189729 VS.IRATHO.SuccOutCS.DR Number of Successful CS Outgoing Inter-RAT Handovers Based on Directed Retry for Cell


67189730 VS.IRATHO.AttRelocPrepOutCS.DR

Number of Preparation Attempts for CS Outgoing Inter-RAT Handover Based on Directed Retry for Cell


67189732 VS.IRATHO.SuccRelocPrepOutCS.DR

Number of Successful Preparations for CS Outgoing Inter-RAT Handover Based on Directed Retry for Cell


67189749 IRATHO.AttRelocPrepOutCS Number of Preparation Attempts for CS Outgoing Inter-RAT Handover for Cell

WRFD-02040002

WRFD-020303

WRFD-020305

WRFD-020306

Inter System Direct Retry

Inter-RAT Handover Based on Coverage

Inter-RAT Handover Based on Service

Inter-RAT Handover Based on Load

../RNCCounterHtml/mbsc/m-perf/Mt-10788.html






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7-2

Counter ID



67189750 IRATHO.SuccRelocPrepOutCS

Number of Successful Preparations for CS Outgoing Inter-RAT Handover for Cell

WRFD-02040002

WRFD-020303

WRFD-020305

WRFD-020306





67189751 IRATHO.FailRelocPrepOutCS.TAlExp

Number of Failed Preparations for CS Outgoing Inter-RAT Handover for Cell (TRELOCalloc expiry)

WRFD-02040002

WRFD-020303

WRFD-020305

WRFD-020306





67189752 IRATHO.FailRelocPrepOutCS.TgtFail

Number of Failed Preparations for CS Outgoing Inter-RAT Handover for Cell (Relocation Failure in Target CN/RNC or Target System)

WRFD-02040002

WRFD-020303

WRFD-020305

WRFD-020306





67189753 IRATHO.FailRelocPrepOutCS.ReloNoSup

Number of Failed Preparations for CS Outgoing Inter-RAT Handover for Cell (Relocation not supported in Target RNC or Target system)

WRFD-02040002

WRFD-020303

WRFD-020305

WRFD-020306





67189754 IRATHO.AttOutCS Number of CS Outgoing Inter-RAT Handover Attempts

WRFD-02040002

WRFD-020303

WRFD-020305

WRFD-020306





67189755 IRATHO.SuccOutCS Number of Successful CS Outgoing Inter-RAT Handovers for Cell

WRFD-02040002

WRFD-020303

WRFD-020305

WRFD-020306










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7-3

Counter ID




67189756 IRATHO.FailOutCS.CfgUnsupp

Number of Failed CS Outgoing Inter-RAT Handovers for Cell (Configuration Unsupported)

WRFD-02040002

WRFD-020303

WRFD-020305

WRFD-020306





67189757 IRATHO.FailOutCS.PhyChFail Number of Failed CS Outgoing Inter-RAT Handovers for Cell (Physical Channel Failure)

WRFD-02040002

WRFD-020303

WRFD-020305

WRFD-020306





67189758 VS.IRATHO.AttRelocPrepInCS Number of Preparations for CS Incoming Inter-RAT Handover for Cell

WRFD-02040002

WRFD-020303

WRFD-020305

WRFD-020306





67189759 VS.IRATHO.SuccInCS Number of Successful CS Incoming Inter-RAT Handovers for Cell

WRFD-02040002

WRFD-020303

WRFD-020305

WRFD-020306





67189760 VS.IRATHO.FailRelocPrepInCS.TRNCSysFailReloc

Number of Failed Preparations for CS Incoming Inter-RAT Handover (Relocation failure in target CN/RNC or target system)

WRFD-02040002

WRFD-020303

WRFD-020305

WRFD-020306





67189761 VS.IRATHO.FailRelocPrepInCS.TRNCSysRelocUnsupp

Number of Failed Preparations for CS Incoming Inter-RAT Handover

WRFD-02040002

WRFD-020303

WRFD-020305

WRFD-020306



Inter-RAT Handover







WCDMA RAN




7-4

Counter ID



(Relocation not supported in target RNC or target system)

Based on Service


67189762 VS.IRATHO.FailRelocPrepInCS.ResUnavail

Number of Failed Preparations for CS Incoming Inter-RAT Handover (No resource available)

WRFD-02040002

WRFD-020303

WRFD-020305

WRFD-020306





67190410 VS.IRATHO.FailInCS.NoReply Number of Failed CS Inter-RAT Incoming Handovers Due to No Response from UE for Cell

WRFD-02040002

WRFD-020303

WRFD-020305

WRFD-020306





67190414 VS.IRATHO.SuccRelocPrepInCS

Number of Successful preparations for CS Incoming Inter-RAT Handovers for Cell

WRFD-02040002

WRFD-020303

WRFD-020305

WRFD-020306





67192186 IRATHO.FailRelocPrepOutCS.HigherTrafficLod

Number of Failed Preparations for CS Outgoing Inter-RAT Handover for Cell (Traffic Load In The Target Cell Higher Than In The Source Cell)

WRFD-02040002

WRFD-020303

WRFD-020305

WRFD-020306





67192187 VS.IRATHO.FailRelocPrepInCS.TgtHighLoad

Number of Failed Preparations for CS Incoming Inter-RAT Handover (Traffic Load In The Target Cell Higher Than In The Source Cell)

WRFD-02040002

WRFD-020303

WRFD-020305

WRFD-020306





67192389 VS.DRD.RBSetup.AttOut Number of RB WRFD-02040001 Intra System Direct Retry







WCDMA RAN




7-5

Counter ID



Setup Attempts for Outgoing Inter-Frequency Directed Retry for Cell

67192390 VS.DRD.RBSetup.SuccOut Number of Successful RB Setup for Outgoing Inter-Frequency Directed Retry for Cell


67192391 VS.DRD.RBSetup.AttIn Number of RB Setup Attempts for Incoming Inter-Frequency Directed Retry for Cell


67192392 VS.DRD.RBSetup.SuccIn Number of Successful RB Setup for Incoming Inter-Frequency Directed Retry for Cell


67192393 VS.DRD.RBRecfg.AttOut Number of RB Reconfiguration Attempts for Outgoing Inter-Frequency Directed Retry for Cell


67192394 VS.DRD.RBRecfg.SuccOut Number of Successful RB Reconfiguration for Outgoing Inter-Frequency Directed Retry for Cell


67192395 VS.DRD.RBRecfg.AttIn Number of RB Reconfiguration Attempts for Incoming Inter-Frequency Directed Retry for Cell


67192396 VS.DRD.RBRecfg.SuccIn Number of WRFD-02040001 Intra System Direct Retry








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7-6

Counter ID



Successful RB Reconfiguration for Incoming Inter-Frequency Directed Retry for Cell

67192440 VS.DRD.RB.D2H.AttOut Number of Outgoing DCH-to-HSDPA Directed Retry Attempts for Cell

WRFD-01061112

WRFD-02040001

HSDPA DRD


67192441 VS.DRD.RB.D2H.SuccOut Number of Successful Outgoing DCH-to-HSDPA Directed Retry for Cell

WRFD-01061112

WRFD-02040001

HSDPA DRD


67192442 VS.DRD.RB.D2H.AttIn Number of Incoming DCH-to-HSDPA Directed Retry Attempts for Cell

WRFD-01061112

WRFD-02040001

HSDPA DRD


67192443 VS.DRD.RB.D2H.SuccIn Number of Successful Incoming DCH-to-HSDPA Directed Retry for Cell

WRFD-01061112

WRFD-02040001

HSDPA DRD


67192444 VS.DRD.RB.D2H.Att.RNC Number of DCH-to-HSDPA Directed Retry Attempts for RNC

WRFD-01061112

WRFD-02040001

HSDPA DRD


67192445 VS.DRD.RB.D2H.Succ.RNC Number of Successful DCH-to-HSDPA Directed Retry for RNC

WRFD-01061112

WRFD-02040001

HSDPA DRD


67192607 VS.RRC.Estab.DRDIn Number of RRC Connection Setup Attempts with DRD in for Cell

WRFD-02040001

WRFD-010510


3.4/6.8/13.6/27.2Kbps RRC Connection and Radio Access Bearer Establishment and Release

67192658 IRATHO.FailRelocPrepOutCS.NoResAvail

Number of Failed Preparations for


Inter-RAT Handover









WCDMA RAN




7-7

Counter ID



CS Outgoing Inter-RAT Handover for Cell (No Resource Available)

WRFD-020303

WRFD-020305

WRFD-020306

Based on Coverage



67192659 IRATHO.FailRelocPrepOutCS.UKnowRNC

Number of Failed Preparations for CS Outgoing Inter-RAT Handover for Cell (Unknown Target RNC)

WRFD-02040002

WRFD-020303

WRFD-020305

WRFD-020306





67192660 VS.IRATHO.FailOutCS.NoReply

Number of Times that the Timer Waiting for Iu Release Command Expires in CS Outgoing Inter-RAT Handover for Cell

WRFD-02040002

WRFD-020303

WRFD-020305

WRFD-020306





67195503 VS.DRD.RB.D2E.AttOut Number of Outgoing DCH-to-HSUPA Directed Retry Attempts for Cell


67195504 VS.DRD.RB.D2E.SuccOut Number of Successful DCH-to-HSUPA Directed Retry for Cell


67195505 VS.DRD.RB.D2E.AttIn Number of Incoming DCH-to-HSUPA Directed Retry Attempts for Cell


67195506 VS.DRD.RB.D2E.SuccIn Number of Successful Incoming DCH-to-HSUPA Directed Retry for Cell


67196293 VS.DRD.IFREQ.CS.MBDR.RBSetup.AttOut

Number of CS Voice Directed

WRFD-020103

WRFD-020402

Inter Frequency Load Balance








WCDMA RAN




7-8

Counter ID



Retry Attempts Based on Inter-Frequency Measurement for Cell

Measurement Based Direct Retry

67196294 VS.DRD.IFREQ.CS.MBDR.RBSetup.SuccOut

Number of Successful CS Voice Directed Retry Based on Inter-Frequency Measurement for Cell

WRFD-020103

WRFD-020402



67196295 VS.DRD.IFREQ.PS.MBDR.R99.RBSetup.AttOut

Number of PS R99 Directed Retry Attempts Based on Inter-Frequency Measurement for Cell

WRFD-020103

WRFD-020402



67196296 VS.DRD.IFREQ.PS.MBDR.R99.RBSetup.SuccOut

Number of Successful PS R99 Directed Retry Based on Inter-Frequency Measurement for Cell

WRFD-020103

WRFD-020402



67196297 VS.DRD.IFREQ.PS.MBDR.HResCong.RBSetup.AttOut

Number of HSDPA PS Directed Retry Attempts Based on Inter-Frequency Measurement for Cell

WRFD-020103

WRFD-020402



67196298 VS.DRD.IFREQ.PS.MBDR.HResCong.RBSetup.SuccOut

Number of Successful HSDPA PS Directed Retry Based on Inter-Frequency Measurement for Cell

WRFD-020103

WRFD-020402



67196299 VS.IRATHO.AttOutCS.MBDR Number of CS Outgoing Inter-RAT Handover Attempts Based on Measurement

WRFD-02040002

WRFD-020402









WCDMA RAN




7-9

Counter ID



for Cell

67196300 VS.IRATHO.SuccOutCS.MBDR

Number of Successful CS Outgoing Inter-RAT Handovers Based on Measurement for Cell

WRFD-02040002

WRFD-020402



73394014 VS.IRATHO.AttInCS Number of CS Incoming Inter-RAT Handover Attempts for Cell

WRFD-02040002

WRFD-020303

WRFD-020305

WRFD-020306





73394035 VS.IRATHO.AttRelocPrepOutCS.DR.GCell

Number of CS Outgoing Inter-RAT Handover Preparation Attempts (Directed retry)

WRFD-02040002

WRFD-020303

WRFD-020305

WRFD-020306





73394053 VS.DRD.PhyRecfg.AttOut Number of Outgoing DRD Attempts through Physical Channel Reconfiguration for Cell

WRFD-020103

WRFD-02040001



73394054 VS.DRD.PhyRecfg.SuccOut Number of Successful Outgoing DRDs through Physical Channel Reconfiguration for Cell

WRFD-020103

WRFD-02040001



73394055 VS.DRD.PhyRecfg.AttIn Number of Incoming DRD Attempts through Physical Channel Reconfiguration for Cell

WRFD-020103

WRFD-02040001



73394056 VS.DRD.PhyRecfg.SuccIn Number of WRFD-020103 Inter Frequency Load








WCDMA RAN




7-10

Counter ID



Successful Incoming DRDs through Physical Channel Reconfiguration for Cell

WRFD-02040001 Balance


73421487 VS.DRD.RBSetup.AttEstab.RollBack

Number of RB Setup Attempts After the RB Setup DRD Rollback


73421488 VS.DRD.RBSetup.SuccEstab.RollBack

Number of successful RB Setups After the RB Setup DRD Rollback


73421489 VS.DRD.RBRecfg.AttEstab.RollBack

Number of RB Reconfiguration Attempts After the RB Reconfiguration DRD Rollback


73421490 VS.DRD.RBRecfg.SuccEstab.RollBack

Number of Successful RB Reconfigurations After the RB Reconfiguration DRD Rollback


73421491 VS.DRD.PhyRecfg.AttEstab.RollBack

Number of Physical Channel Reconfiguration Attempts After the Physical Channel Reconfiguration DRD Rollback


73421492 VS.DRD.PhyRecfg.SuccEstab.RollBack

Number of Successful Physical Channel Reconfigurations After the Physical Channel Reconfiguration DRD Rollback








WCDMA RAN




7-11

Counter ID



73421842 VS.DRD.RB.F2H.AttOut Number of Outgoing FACH-to-HSDPA Directed Retry Attempts for Cell

WRFD-01061112

WRFD-02040001

HSDPA DRD


73421843 VS.DRD.RB.F2H.SuccOut Number of Successful Outgoing FACH-to-HSDPA Directed Retries for Cell

WRFD-01061112

WRFD-02040001

HSDPA DRD


73421844 VS.DRD.RB.F2E.AttOut Number of Outgoing FACH-to-HSUPA Directed Retry Attempts for Cell


73421845 VS.DRD.RB.F2E.SuccOut Number of Successful Outgoing FACH-to-HSUPA Directed Retries for Cell


73421846 VS.DRD.RB.F2H.AttIn Number of Incoming FACH-to-HSDPA Directed Retry Attempts for Cell

WRFD-01061112

WRFD-02040001

HSDPA DRD


73421847 VS.DRD.RB.F2H.SuccIn Number of Successful Incoming FACH-to-HSDPA Directed Retries for Cell

WRFD-01061112

WRFD-02040001

HSDPA DRD


73421848 VS.DRD.RB.F2E.AttIn Number of Incoming FACH-to-HSUPA Directed Retry Attempts for Cell


73421849 VS.DRD.RB.F2E.SuccIn Number of Successful Incoming FACH-to-HSUPA Directed Retries for Cell










WCDMA RAN

Directed Retry Decision 8 Glossary



8-1

8 Glossary

For the acronyms, abbreviations, terms, and definitions, see the Glossary.

Glossary.htm

WCDMA RAN

Directed Retry Decision 9 Reference Documents



9-1

9 Reference Documents

[1] Call Admission Control Feature Parameter Description

[2] Load Control Feature Parameter Description

[3] BSC6900 UMTS Performance Counter Reference

Call%20Admission%20Control.htm

Load%20Control.htm