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Page 1: Huawei 2g Handover

HUAWEI GSM Base Station SubsystemGBSS8.1

BSS Feature Parameter Description

Issue 01

Date 2009–04–30

HUAWEI TECHNOLOGIES CO., LTD.

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Copyright © Huawei Technologies Co., Ltd. 2010. All rights reserved.No part of this document may be reproduced or transmitted in any form or by any means without prior writtenconsent of Huawei Technologies Co., Ltd. Trademarks and Permissions

and other Huawei trademarks are trademarks of Huawei Technologies Co., Ltd.All other trademarks and trade names mentioned in this document are the property of their respective holders. NoticeThe purchased products, services and features are stipulated by the contract made between Huawei and thecustomer. All or part of the products, services and features described in this document may not be within thepurchase scope or the usage scope. Unless otherwise specified in the contract, all statements, information,and recommendations in this document are provided "AS IS" without warranties, guarantees or representationsof any kind, either express or implied.

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

Huawei Technologies Co., Ltd.Address: Huawei Industrial Base

Bantian, LonggangShenzhen 518129People's Republic of China

Website: http://www.huawei.com

Email: [email protected]

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About This Document

PurposeBSS features consist of basic BSS features and optional BSS features. This document describesthe following aspects of the BSS features:

l Change History

l Overview

l Technical Description

l Engineering Guidelines

l Maintenance Information

l Reference Documents

Product VersionThe following table lists the product versions related to this document.

Product Name Product Model Product Version

BSC BSC6000 Refer to the version information in each feature.

BTS BTS3012 Refer to the version information in each feature.

BTS3012AE Refer to the version information in each feature.

BTS3006C Refer to the version information in each feature.

BTS3002E Refer to the version information in each feature.

BTS3900 GSM Refer to the version information in each feature.

BTS3900A GSM Refer to the version information in each feature.

DBS3900 GSM Refer to the version information in each feature.

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Target GroupsThis document is intended for people who have:l Basic GSM knowledge

l Working experience on GSM

Organization1 Handover

ConventionsSymbol Conventions

The symbols that may be found in this document are defined as follows.

Symbol Description

Indicates a hazard with a high level of risk, which if notavoided,will result in death or serious injury.

Indicates a hazard with a medium or low level of risk, whichif not avoided, could result in minor or moderate injury.

Indicates a potentially hazardous situation, which if notavoided,could result in equipment damage, data loss,performance degradation, or unexpected results.

Indicates a tip that may help you solve a problem or savetime.

Provides additional information to emphasize or supplementimportant points of the main text.

General Conventions

The general conventions that may be found in this document are defined as follows.

Convention Description

Times New Roman Normal paragraphs are in Times New Roman.

Boldface Names of files, directories, folders, and users are inboldface. For example, log in as user root.

Italic Book titles are in italics.

Courier New Examples of information displayed on the screen are inCourier New.

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Command Conventions

The command conventions that may be found in this document are defined as follows.

Convention Description

Boldface The keywords of a command line are in boldface.

Italic Command arguments are in italics.

[ ] Items (keywords or arguments) in brackets [ ] are optional.

{ x | y | ... } Optional items are grouped in braces and separated byvertical bars. One item is selected.

[ x | y | ... ] Optional items are grouped in brackets and separated byvertical bars. One item is selected or no item is selected.

{ x | y | ... }* Optional items are grouped in braces and separated byvertical bars. A minimum of one item or a maximum of allitems can be selected.

[ x | y | ... ]* Optional items are grouped in brackets and separated byvertical bars. Several items or no item can be selected.

GUI Conventions

The GUI conventions that may be found in this document are defined as follows.

Convention Description

Boldface Buttons, menus, parameters, tabs, window, and dialog titlesare in boldface. For example, click OK.

> Multi-level menus are in boldface and separated by the ">"signs. For example, choose File > Create > Folder.

Keyboard Operations

The keyboard operations that may be found in this document are defined as follows.

Format Description

Key Press the key. For example, press Enter and press Tab.

Key 1+Key 2 Press the keys concurrently. For example, pressing Ctrl+Alt+A means the three keys should be pressed concurrently.

Key 1, Key 2 Press the keys in turn. For example, pressing Alt, A meansthe two keys should be pressed in turn.

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Mouse Operations

The mouse operations that may be found in this document are defined as follows.

Action Description

Click Select and release the primary mouse button without movingthe pointer.

Double-click Press the primary mouse button twice continuously andquickly without moving the pointer.

Drag Press and hold the primary mouse button and move thepointer to a certain position.

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Contents

About This Document...................................................................................................................iii

1 Handover......................................................................................................................................1-11.1 Change History................................................................................................................................................1-21.2 Overview.........................................................................................................................................................1-61.3 Technical Description.....................................................................................................................................1-9

1.3.1 Overview................................................................................................................................................1-91.3.2 Measurement Report Processing..........................................................................................................1-151.3.3 Handover Preprocessing.......................................................................................................................1-171.3.4 Handover Decision Based on Handover Algorithm I..........................................................................1-201.3.5 Handover Decision Based on Handover Algorithm II.........................................................................1-37

1.4 Maintenance Information..............................................................................................................................1-541.5 Reference Documents...................................................................................................................................1-86

Index.................................................................................................................................................i-1

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Figures

Figure 1-1 Procedure for performing Huawei handover algorithms....................................................................1-9Figure 1-2 Procedure of handover decision based on handover algorithm I......................................................1-11Figure 1-3 Handover decisions based on handover algorithm I.........................................................................1-13Figure 1-4 Procedure of handover decision based on handover algorithm II....................................................1-14Figure 1-5 Handover decisions based on handover algorithm II.......................................................................1-15Figure 1-6 Load handover between cells............................................................................................................1-30Figure 1-7 Load handover..................................................................................................................................1-31Figure 1-8 Edge handover..................................................................................................................................1-32Figure 1-9 Fast-moving micro cell handover.....................................................................................................1-33Figure 1-10 Cell layers.......................................................................................................................................1-34Figure 1-11 Handovers with high priority..........................................................................................................1-38Figure 1-12 Handovers with normal priority.....................................................................................................1-39Figure 1-13 Edge handover................................................................................................................................1-48Figure 1-14 Fast-moving micro cell handover...................................................................................................1-49Figure 1-15 Cell layers.......................................................................................................................................1-51

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Tables

Table 1-1 NEs involved in handover....................................................................................................................1-9Table 1-2 Parameters related to the number of measurement reports................................................................1-17Table 1-3 Parameters related to handover penalty.............................................................................................1-18Table 1-4 Parameters related to handover..........................................................................................................1-54Table 1-5 Counters related to handover.............................................................................................................1-60

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1 Handover

About This Chapter

1.1 Change History

1.2 Overview

1.3 Technical Description

1.4 Maintenance Information

1.5 Reference Documents

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1.1 Change HistoryThe change history provides information on the changes in different document versions.

Document and Product VersionsDocumentVersion

BSS Version BSC Version BTS Version

01(2009-04-30) 8.1 V900R008C12 V300R008

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

l Feature changeFeature change refers to the change in the Handover feature of a specific product version.

l Editorial changeEditorial change refers to the change in wording or the addition of the information that wasnot described in the earlier version.

01(2009-04-30)This is the first commercial release of BSS8.1.

Compared with issue 02 (2008-06-30) of BSS8.0,issue 01 (2009-04-30) of BSS8.1 incorporatesthe changes described in the following table.

ChangeType

Change Description Parameter Change

Featurechange

The following contents areupdated and added:l 1.3.3 Handover

Preprocessingl Enhanced Dual-Band

Network Handover

The added parameter is listed asfollows:Penalty Time after AMR TCHF-H HOFail(s)

Handover algorithm II is added,and the original handoveralgorithm is called handoveralgorithm I.

The added parameter is listed asfollows:HO Control Switch

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ChangeType

Change Description Parameter Change

Compared with handoveralgorithm I, handover algorithmII provides great change inhandover decision procedure andclassification. The details are asfollows:l The handover penalty is

performed after the networkcharacteristics adjustment andbefore the emergencyhandover decision.

l The network characteristicsadjustment is performed (forsome factors) before theemergency handover decisionprocedure is initiated. Thenetwork characteristicsadjustment is performed again(for all factors) after the loadhandover decision is made.

l The comprehensive handoverdecision is made and thecandidate neighboring cells aredetermined.

l The classification of handoverdecision is changed.

l The conditions for triggeringthe handovers and for selectingthe target cell are changed. Thehandovers are listed as follows:TA Handover, BQHandover, InterferenceHandover, No DownlinkMeasurement ReportHandover, Enhanced Dual-Band Network Handover,Load Handover, and Fast-Moving Micro CellHandover.

The added parameters are listed asfollows:l Penalty Time on Load HO

l Penalty Value on Load HO

l Penalty Time on Interfere HO

l TA HO Watch Time

l TA HO Valid Time

l BQ HO Watch Time

l BQ HO Valid Time

l Interfere HO Static Time

l Interfere HO Valid Time

l UL BQ HO Static Time

l UL BQ HO Last Time

l HCS HO Watch Time

l HCS HO Valid Time

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ChangeType

Change Description Parameter Change

The following handover decisionsare not contained in handoveralgorithm II:l Rapid Level Drop Handover

l Independent load handover

l PBGT Handover

l Inter-Layer Handover

l Handover due to MSmovement to the border of theoverlaid cell

None.

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ChangeType

Change Description Parameter Change

The following handover decisionsare added to handover algorithmII:l Better Cell Handover

l Handover Between a Full-Rate TCH and a Half-RateTCH

The added parameters are listed asfollows:l Better Cell Handover Enable

l Better Cell HO Watch Time

l Better Cell HO Valid Time

l Pathloss Ho. Enable

l IntraCell AMR TCHF-TCHH HoAllowed

l IntraCell AMR TCHF-TCHH HoPathloss Threshold

l IntraCell AMR TCHF-TCHH HoATCB Threshold

l IntraCell AMR TCHF-TCHH HoQual. Threshold

l IntraCell TCHF-TCHH Ho StatTime(s)

l IntraCell TCHF-TCHH Ho LastTime(s)

l IntraCell Non-AMR TCHF-TCHHHo Allowed

l IntraCell Non-AMR TCHF-TCHHHo Pathloss Threshold

l IntraCell Non-AMR TCHF-TCHHHo ATCB Threshold

l IntraCell Non-AMR TCHF-TCHHHo Qual. Threshold

l IntraCell TCHF-TCHH Ho StatTime(s)

l IntraCell TCHF-TCHH Ho LastTime(s)

l IntraCell AMR TCHH-TCHF QualHo Allowed

l IntraCell AMR TCHH-TCHF HoPathloss Threshold

l IntraCell AMR TCHH-TCHF HoATCB Threshold

l IntraCell AMR TCHH-TCHF HoQual. Threshold

l IntraCell TCHH-TCHF Ho StatTime(s)

l IntraCell TCHH-TCHF Ho LastTime(s)

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ChangeType

Change Description Parameter Change

l IntraCell Non-AMR TCHH-TCHFQual. Ho Allowed

l IntraCell Non-AMR TCHH-TCHFHo Pathloss Threshold

l IntraCell Non-AMR TCHH-TCHFHo ATCB Threshold

l IntraCell Non-AMR TCHH-TCHFHo Qual. Threshold

Descriptions of handoveralgorithm II are added to 1.3.2Measurement ReportProcessing.

None.

Editorialchange

The structure of the document isoptimized.

None.

The following contents areupdated and added:l The definition of ATCB is

added to 1.2 Overview.l 1.3.3 Handover

Preprocessing is divided into1.3.2 Measurement ReportProcessing and 1.3.3Handover Preprocessing toimprove the readability.

l In TA Handover, thedescription of handoverpenalty is moved toLimitations in TA Handover.

l In BQ Handover, thedescription of handoverpenalty is moved toLimitations in BQ Handover.

None.

1.2 Overview

IntroductionThe GSM network comprises several cells with continuous coverage. The handover techniqueis introduced into the GSM system to enable the users who are in motion to continue with thecurrent call without interruption, thus optimizing the network performance.

During a handover, the MS and BTS in service measure the conditions of uplink and downlinkradio links respectively, record the measurement results into measurement reports (MRs), and

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then send the MRs to the BSC. The BSC determines whether to trigger a handover based on theMRs and the actual conditions of the radio network.

Target GroupsThis document is intended for people who have:

l Basic GSM knowledge

l Working experience on GSM

TermsTerm Definition

Ping-ponghandover

Ping-pong handover refers to the condition in which an MS is handed over backand forth between two cells because of the changes in signal quality or theimproper settings of parameters.

Co-siteneighboring cells

Neighboring cells in the same BTS.

Raileighfading

Raileigh fading is related to frequency. In radio propagation, signals inevitablyundergo short-period amplitude changes. In other words, signal fading isfrequency-specific.

Chainneighboring cell

Chain neighboring cell is one of the configuration properties for a neighboringcell. During a quick handover, an MS is handed over to only the chainneighboring cells of the serving cell. Generally, the neighboring cells of theserving cell in the fast-moving direction of the MS are configured as chainneighboring cells. The configurations depend on the actual conditions.

ATCB ATCB specifies how close the MS is to the cell center. If the ATCB is greater,the MS is closer to the cell center.

ATCBhandover

ATCB handover is a special method of determining the border between anoverlaid cell and an underlaid cell in the enhanced dual-band network. Thecoverage area of the overlaid cell is determined by ATCB_THRD,ATCB_HYST, and the signal strength difference between serving cell andneighboring cell.

Frequencyoffset

When the transmit source of the radio wave is far from the receiving party, thewavelength is long and the frequency is low. When the transmit source is closeto the receiving party, the wavelength is short and the frequency is high. TheBTS of the serving cell can calculate the frequency offset (indicated by Δf)through the signals transmitted by the moving MS. If the absolute value of Δfis great, you can infer that the MS moves at a high speed. If Δf is a positivenumber, you can infer that the MS is moving towards the BTS. If Δf is a negativenumber, you can infer that the MS is moving away from the BTS.

Differentfrequencies set

In FH mode, the different frequencies set refers to a certain FH group. In non-FH mode, the different frequencies set refers to a certain frequency.

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Term Definition

Enhancedmeasurement report

The enhanced measurement report is a new downlink measurement report thatis provided by the MS. Compared with the normal measurement report, theenhanced measurement report is added with new contents, such as BER andFER. The enhanced measurement report provides the measurement informationof up to 15 neighboring GSM/WCDMA cells, whereas the normal measurementreport provides the measurement information of 6 neighboring GSM cells atmost.

FULLSET

The FULL SET specifies the receive level and signal quality measured on TCHwhen the BTS transmits signals at full power.

SUB SET The SUB SET specifies the receive level and signal quality measured on TCHwhen the DTX function is enabled.

Ec/No Ec/No means Signal Noise Ratio in WCDMA. It maps with C/I in GSM.

Acronyms and Abbreviations

Acronym andAbbreviation Expansion

MS Mobile Station

BSC Base Station Controller

MR Measurement Report

BQ Bad Quality

TA Timing Advance

BSIC Base Station Identity Code

BER Bit Error Ratio

BCCH Broadcast Control Channel

AMR Adaptive Multi Rate

ATCB Adapter distance To Cell Border

RQI Radio Quality Indication

RSCP Received Signal Code Power

CPICH Common PIlot CHannel

PBGT Power BudGet Handover

Network Elements Involved

Table 1-1 lists the network elements (NEs) involved in handover.

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Table 1-1 NEs involved in handover

MS BTS BSC MSC MGW SGSN GGSN HLR

√ √ √ √ – – – –

NOTE

l -: not involved

l √: involved

1.3 Technical Description

1.3.1 Overview

Huawei handover algorithms (handover algorithm I and handover algorithm II) involvemeasurement and MR reporting, MR processing, handover decision, and handover execution.

NOTE

Huawei handover algorithms apply to the handovers on TCHs as well as the handovers on SDCCHs.

You can determine the handover algorithm used in a cell through HO Control Switch.

Figure 1-1 shows the procedure for performing Huawei handover algorithms (includinghandover algorithm I and handover algorithm II).

Figure 1-1 Procedure for performing Huawei handover algorithms

Start

MS in connection state

MS performs measurement and MR reporting

End

BSS performs MR processing

Handover decision based on handover algorithm

Handover execution

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Handover Decision Based on Handover Algorithm IFigure 1-2 shows the procedure of handover decision based on handover algorithm I.

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Figure 1-2 Procedure of handover decision based on handover algorithm I

Start

No downlink measurement report handover decision

MS starts minimum interval protection

Other handover decisions

Determines target cell according to 2G/3G priority selection conditions

and corresponding thresholds

Starts minimum interval protection of consecutive handovers

End

Yes

Yes

No

Handover penalty

Basic queuing

Network characteristics adjustment

Forced handover

Quick handover

No

Handover preprocessing

Whether minimum interval protection of consecutive

handovers times out?

Whether minimum interval protection of handover times

out?

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In handover algorithm I, five types of handover decisions are defined:

l Quick handover (including quick PBGT handover and frequency offset handover). Goodand stable services can be provided when the voice quality deteriorates during the fastmovement of an MS. Quick handover is mainly applicable in the railway scenario.

l Emergency handover. Emergency handover can ensure the call continuity when the radioenvironment severely deteriorates. Theoretically, the emergency handover has a biggerdeviation than other handovers in terms of the selection of the target cell. In a normal cell,frequent emergency handovers should be avoided.

l Enhanced dual-band network handover. In an enhanced dual-band network, the resourcesin the overlaid DCS1800 cell and underlaid GSM900 cell can be shared during theassignment and handover procedures. That is, the calls in the high-traffic GSM900 cell canbe handed over to the low-traffic DCS1800 cell to balance traffic.

l Load handover. Load handover enables the system load to be balanced among multiplecells so that the system performance can be ensured.

l Normal handover. Normal handover ensures good services when an MS is moving.

Figure 1-3 shows the handovers provided in Figure 1-2 and their priorities in handoveralgorithm I.

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Figure 1-3 Handover decisions based on handover algorithm I

Emergency handover

Normal handover

Starts protection timer after emergency handover is

triggered.

TA handover

Interference handover

Rapid level drop handover

BQ handover

Enhanced dual-band network handover

Load handover

Edge handover

Fast-moving micro cell handover

Inter-layer handover

PBGT handover

Concentric cell handover

AMR handover

TIGHT BCCH handover

3G better cell handover

Handover Decision Based on Handover Algorithm IIFigure 1-4 shows the procedure of handover decision based on handover algorithm II.

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Figure 1-4 Procedure of handover decision based on handover algorithm II

Start

No downlink measurement report handover decision

MS starts minimum interval protection

Emergency handover (not including quick handover)

Performs comprehensive decision of handover result and determines

candidate neighbor cell

Starts minimum interval protection of consecutive handovers

End

Yes

Yes

No

Basic queuing

Network characteristics adjustment (some factors)

Forced handover

Handover penalty

Quick handover (emergency handover)

No

Handover preprocessing

Other handover decisions

Network characteristics adjustment (all factors)

Load handover decision

Whether minimum interval protection of consecutive

handovers times out?

Whether minimum interval protection of consecutive

handovers times out?

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In handover algorithm II, three types of handover decisions are defined, as shown in Figure1-5.

Figure 1-5 Handover decisions based on handover algorithm II

Emergency handover Intra-cell handover

TIGHT BCCH handover

Inter-cell handoverFast-moving micro cell

handover

Enhanced dual-band network handover

Better cell handover

Quick handover

TA handover

BQ handover

Edge handover

Interference handover

Concentric cell handover

AMR handover

Handover between a full-rate TCH and a half-rate

TCH 3G better cell handover

Handover ExecutionThe parameter Power boost before HO enabled or not determines whether the BTS of theserving cell transmits signals at the maximum power during a handover. If Power boost beforeHO enabled or not is set to StartUp, the BSC maximizes the transmit power of the BTS beforesending a handover command to the MS. The BSC does not adjust the BTS power during thehandover to ensure the success of the handover.

1.3.2 Measurement Report Processing

Measurement report processing involves measurement report interpolation and filtering.

NE Selection for Measurement Report ProcessingThe processing can be performed either on the BSC side or on the BTS side.

l If MR.Preprocessing is set to No, then the processing is performed on the BSC side.

l If MR.Preprocessing is set to Yes, then the processing is performed on the BTS side. Bysetting the parameters Transfer Original MR, Transfer BS/MS Power Class, and SentFreq.of Preprocessed MR, you can specify the contents of the MRs to be provided andthe period during which the MRs are provided. This decreases the signaling traffic on theAbis interface and the traffic volume processed by the BSC.

Data Selection for Measurement ReportThe MR can be classified into enhanced MR and normal MR. The parameter Report Typedetermines the type to be used.

In the MR, the TCH measurement of the serving cell is classified into FULL SET and SUB SET.The MRs from the MS and BTS specify whether the DTX is adopted.

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l DtxMeasUsed is set to Open.– If the MR specifies that the DTX is used, the SUB SET value should be selected.– If the MR specifies that the DTX is not used, the FULL SET value should be selected.

l DtxMeasUsed is set to Close.– If the MR specifies that the DTX is not used, the FULL SET value should be selected.– If the MR specifies that the DTX is used, the SUB SET value should be selected. The

SUB SET value should be used regardless of the usage state of the DTX that the MRspecifies.

Measurement Report InterpolationThe neighboring cell indexes are found on the basis of the BCCH frequencies and BSICsprovided by the MS. Then, the uplink and downlink measurement results are obtained from themeasurement reports.

l If measurement reports are issued continuously, they are directly added to the measurementreport list.

l If measurement reports are not issued continuously and the number of lost measurementreports is smaller than the value of Allowed M.R Number Lost, the system performsoperations as follows:– For the serving cell, the handover algorithm I performs the linear interpolation for the

MRs. The lowest values are applied to the interpolation of MRs by the handoveralgorithm II according to the protocols; that is, level 0 (-110 dBm) and quality 7 areapplied in the interpolation.

– For the neighboring cell, the lowest value is applied to the lost level value according tothe protocols; that is, level 0 (-110 dBm) is applied in the interpolation.

NOTE

If no MR is reported because the RX level in the neighboring cell is too low, level 0 (-110 dBm)is applied in the interpolation.

l If measurement reports are not issued continuously and the number of lost measurementreports is greater than the value of Allowed M.R Number Lost, the previous measurementreports are discarded. When new measurement reports are issued, calculation is done again.

Measurement Report FilteringFiltering is performed on measurement reports obtained continuously from the measurementreport list. Averaging is performed on uplink/downlink RX level, uplink/downlink RX quality,TA, RQI, BTS power, 2G neighboring cell level, and the CPICH, RSCP, and Ec/No ofneighboring 3G cell. The averaging minimizes the effect on the result of handover decision dueto sudden changes in the measurement values.

Power control compensation needs to be performed for the downlink RX level of the servingcell by the handover algorithm II. If you compare the RX level of the serving cell after the powercontrol with that of all BCCH TRXs of the neighboring cell, there is no mapping between them.In situations where the cells overlap severely, the handover is easily triggered, thus causing theping-pong handover. After the power control compensation is performed, the RX level of theserving cell can reflect the coverage condition of the BCCH TRX of the serving cell. The powercontrol compensation of the serving cell is performed after the interpolation processing andbefore the filtering processing. In general, the compensation of power control is calculated byadding the downlink RX level of the serving cell and twice the current downlink transmit PowerLevel of the BTS.

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The number of consecutive measurement reports required for filtering is determined by themeasurement object and channel type. See Table 1-2 for details.

Table 1-2 Parameters related to the number of measurement reports

MeasurementObject Channel Type Parameter

Receive level of theserving cell

SDCCH Filter Length for SDCCH Level

TCH Filter Length for TCH Level

Quality of the servingcell

SDCCH Filter Length for SDCCH Qual

TCH Filter Length for TCH Qual

TA of the serving cell TCH Filter Length for TA

SDCCH TA Filter Length for SDCCH Level

Receive level of theneighboring cell

BCCH Filter Length for Ncell RX_LEV

SDCCH NCell Filter Length for SDCCH Level

Power of the BTS inthe serving cell

TCH Filter Length for TCH Level

RQI TCH Filter Length for TCH Qual

If consecutive measurement reports are insufficient, the filtering fails. The handover decision isnot performed.

1.3.3 Handover Preprocessing

Handover Penalty

According to the neighboring cell information in the measurement report and the parameters,the system performs handover preprocessing and adjusts the priorities of the neighboring cells.

The handover penalty is performed after successful fast-moving micro cell handover, TAhandover, BQ handover, fast-moving micro cell handover, OL subcell to UL subcell handoverwithin an enhanced concentric cell, and after the handover failures.

In handover algorithm II, in addition to the situations mentioned above, the handover penalty isalso performed after successful or failed load handover and interference handover.

NOTE

In handover decision procedure of handover algorithm II, the handover penalty is performed after thenetwork characteristics adjustment and before the emergency handover decision.

l After the quick handover, TA handover, BQ handover, or load handover (in handoveralgorithm II) is successfully performed, the penalty level is subtracted from the actual RXlevel of the original cell during the penalty period. Table 1-3 lists the parameters relatedto handover penalty.

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Table 1-3 Parameters related to handover penalty

Handover Parameter

Quickhandover

Quick Handover Punish Time(s)Quick Handover Punish Value(dB)

TA Handover Penalty Level after TA HOPenalty Time after TA HO(s)

BQ Handover Penalty Level after BQ HOPenalty Time after BQ HO(s)

Loadhandover(handoveralgorithm II)

Penalty Time on Load HOPenalty Value on Load HO

l After the fast-moving micro cell handover is successfully performed, penalty is performed

on all the neighboring cells of the micro cell. Related parameters are Penalty on FastMoving Handover and Penalty Time on Fast Moving HO(s).

l If an MS fails to initiate an intra-cell AMR TCHF to TCHH handover, it cannot initiateanother intra-cell AMR TCHF to TCHH handover within Penalty Time after AMRTCHF-H HO Fail(s).

l In handover algorithm II, after the interference handover is initiated, this handover is notallowed to be initiated again within Penalty Time on Interfere HO regardless of whetherthe handover is successful or not.

l After the OL subcell to UL subcell handover within an enhanced concentric cell issuccessful, the handover from UL subcell to OL subcell is not allowed within Penalty Timeof UtoO HO(s).

l After the OL cell to UL cell handover in the enhanced dual-band network is successful, thehandover from UL cell to OL cell is not allowed within Inter UL And OL Subcells HOPenalty Time(s).

l After the handover fails, different penalties are performed on the target cell based on thecauses:– If the handover to a neighboring 2G or 3G cell fails, the actual RX level of the target

cell is subtracted by Penalty Level after HO Fail for neighboring cell ranking duringthe penalty.

NOTE

Based on the handover failure cause, the penalty time could be UmPenaltyTimer,RscPenaltyTimer, or CfgPenaltyTimer.

– If the OL subcell to UL subcell handover within a concentric cell fails, the handoverfrom OL subcell to UL subcell is not allowed within Penalty Time after OtoU HOFail(s).

– If the UL subcell to OL subcell handover within a concentric cell fails, the handoverfrom UL subcell to OL subcell is not allowed within Penalty Time after UtoO HOFail(s).

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Basic RankingBasic ranking is performed after handover penalty to generate a candidate cell list in descendingorder taking the following information into account: RX levels of the serving cell andneighboring cells carried in the MRs, hysteresis, usage of TCHs in the neighboring cells, and soon.

l In the case of non-directed retry, if an MS in an external BSC cell occupies an SDCCH andInter-BSC SDCCH HO ALLowed is set to No, then this cell should be removed from thecandidate cell list. In other words, the handover to this external BSC cell is prohibited.

l If a neighboring 2G cell and the serving cell are controlled by the same BSC and the TCHusage of the neighboring cell is 100%, then the neighboring cell should be removed fromthe candidate cell list; that is, the handover to this neighboring cell is prohibited.

l If the downlink RX level of a neighboring 2G cell is lower than the sum of Min DL Poweron HO Candidate Cell and Min Access Level Offset, then the neighboring cell should beremoved from the candidate cell list; that is, the handover to this neighboring cell isprohibited.

l If the uplink RX level of a neighboring 2G cell is lower than the sum of Min UP Poweron HO Candidate Cell and Min Access Level Offset, then the neighboring cell should beremoved from the candidate cell list; that is, the handover to this neighboring cell isprohibited.

l If a neighboring 3G cell is an FDD cell, the cell is processed according to FDD REPQUANT:– If FDD REP QUANT is set to Ec/N0, and the Ec/N0 of a neighboring cell is lower

than Min Ec/No Threshold, the neighboring cell should be removed from the candidatecell list; that is, the handover to this neighboring cell is prohibited.

– If FDD REP QUANT is set to RSCP, and the RSCP of a neighboring cell is lower thanMin RSCP Threshold, the neighboring cell should be removed from the candidate celllist; that is, the handover to this neighboring cell is prohibited.

l If a neighboring 3G cell is a TDD cell and the RSCP after penalty is lower than the MinRSCP Threshold, the neighboring cell should be removed from the candidate cell list; thatis, the handover to this neighboring cell is prohibited.

l Calculate the difference between the downlink RX level of the neighboring cells and thedownlink RX level of the serving cell. Based on the difference, rank the neighboring cellsin descending order.

Network Characteristics AdjustmentNetwork characteristics adjustment is a process in which the position of each cell in the candidatecell list is determined based on the related network information. Network characteristicsadjustment provides the final candidate cell list for handover decision.

After the network characteristics adjustment, the final candidate cell list (including neighboringcells and serving cell) is generated. The candidate cells are ranked in descending order bypriority. Then, the handover decision procedure starts.

In handover algorithm II, the emergency handover decision is made after the networkcharacteristics adjustment.

After the emergency handover decision, Penalty Value on Load HO is subtracted from thelevel of the original cell within Penalty Time on Load HO (s) if the load handover is successful.The level of the target cell changes after the penalty of load handover; then, the networkcharacteristics needs to be readjusted.

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In handover algorithm I, all related factors are adjusted in network characteristics adjustmentphase; in handover algorithm II, some of the factors are adjusted before the emergency handoverdecision procedure is initiated.

Forced Handover

If the forced handover is triggered, the subsequent handover decisions are not performed.

The purpose of the forced handover is as follows:

l If no TCH is available in the serving cell during the MS access process, the directed retryprocedure is performed when Directed Retry Permitted is set to Yes.

l When BTS maintenance is performed, the MSs under control of the related BTS should behanded over to the cells controlled by a functional BTS to ensure that no call drop occursduring BTS maintenance.

The forced handover is classified into these four types:

l Outgoing cell handover (directed retry)

l Outgoing BTS handover

l Outgoing BSC handover

l Specified target cell list handover

1.3.4 Handover Decision Based on Handover Algorithm I

According to the emergency condition of an MS in the network, the handover decision basedon handover algorithm I is made in the following order: quick handover, emergency handover,enhanced dual-band network handover, load handover, and normal handover.

Handover decision based on handover algorithm I involves the following procedures:

l Determining whether the serving cell meets the triggering conditions

l Selecting corresponding candidate cells

In handover algorithm I, Inter-RAT HO Preference specifies whether a neighboring 2G cellor a neighboring 3G cell is preferred.

l When Inter-RAT HO Preference is set to Preference for 2G Cell:A neighboring 2G cell is preferred. If the candidate cell list contains suitable neighboring3G cells but no suitable neighboring 2G cells, a neighboring 3G cell is selected.

l When Inter-RAT HO Preference is set to Preference for 3G Cell:A neighboring 3G cell is preferred. If the candidate cell list contains suitable neighboring2G cells but no suitable neighboring 3G cells, a neighboring 2G cell is selected.

l When Inter-RAT HO Preference is set to Preference for 2G Cell:If the RX level of a candidate 2G cell is lower than or equal to HO Preference Thresholdfor 2G Cell, a neighboring 3G cell is preferred.

If the triggering conditions of emergency handover are met and there is at least one candidatecell, then the emergency handover timer Min Interval for Emerg.HOs is started. Anotheremergency handover decision can be performed only when Min Interval for Emerg.HOs timesout.

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Quick Handover

Quick handover aims to increase the handover success rate of an MS moving at a high speedand to ensure the call continuity and low call drop rate. Quick handover applies to the scenariowhere an MS moves fast along an urban backbone road, a selected route, or a high-speed railroad.

Quick Handover TypesQuick handover consists of frequency offset handover and quick PBGT handover.

l Frequency offset handoverWhether the MS is moving away from the serving cell is determined based on the frequencyoffset information provided by an MS moving at a high speed. Frequency offset handoverdecision is made according to the uplink/downlink RX level of the serving cell and the pathloss of neighboring cells.

l Quick PBGT handoverQuick PBGT handover decision is made according to the path loss of neighboring cells.

For quick handover, the handover response speed is enhanced by:

l Accurately calculating the moving speed of the MS

l Derestricting the interval between handover decisions

l Reducing the number of measurement reports for the handover decision

l Introducing the α filtering

Quick Handover PreparationThe preparation for quick handover involves the following aspects:

l Frequency offset is decoded from the measurement report.Frequency offset of the MS is obtained from the uplink measurement report that the BTSsends to the BSC.

l α filtering is performed on the measurement report.

Triggering ConditionsDuring handover decision, whether the triggering conditions of frequency offset handover aremet is determined first. When the BTS cannot send the frequency offset information or thereported frequency offset information is invalid, quick PBGT handover is triggered if otherconditions of frequency offset handover are met.

If Quick Handover Enable is set to Yes, the triggering conditions of quick handover are asfollows:

l The MS is moving away from the serving cell (the frequency offset in the measurementresult is a negative value) and the moving speed of the MS is greater than Quick MoveSpeed Threshold(m/s).

l The filtered uplink level of the serving cell is lower than Quick Handover Up TriggerLevel(dB).

l The compensated downlink level of the serving cell is lower than Quick Handover DownTrigger Level(dB).

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l The path loss of configured chain neighboring cells is lower than the specified thresholdof the path loss of the serving cell. In other words, PBGT(n) is greater than or equal to 0.

The triggering conditions of quick handover are as follows:

l If the last three conditions are met simultaneously, the decision is made as follows:

– If the first condition is met, a frequency offset handover is performed.

– If the first condition is not met, a quick PBGT handover is performed.

l If all the last three conditions are not met, quick handover is not triggered.

Target Cell Selection

The target cell must be a chain neighboring cell of the serving cell. The Chain Neighbor Cellparameter specifies whether a neighboring cell is a chain neighboring cell.

Limitations

The limitations on quick handover are as follows:

l The serving cell cannot be selected as the target cell.

l The candidate cells for quick handover must be chain neighboring cells of the serving cell.Each cell can be configured with a maximum of three chain neighboring cells.

l After a quick handover is successful, the penalty is performed on the original cell duringthe penalty time to prevent an immediate handover back to the original cell. The penaltytime and penalty value are specified by Quick Handover Punish Time(s) and QuickHandover Punish Value(dB) respectively.

TA Handover

Timing Advance (TA) handover is a type of emergency handover. The TA handover decisionis made according to the TA value reported by the MS.

The TA value of a normal cell ranges from 0 to 63 and that of an extended cell ranges from 0 to229. The TA can be stepped up or down in steps of 553.5 m. The TA value of 63 correspondsto a distance of 35 km.

Triggering Conditions

TA handover is triggered when the following conditions are met:

l TA HO Allowed is set to Yes.

l Filtered TA value in the measurement report provided by the MS is greater than or equalto TA Threshold.

The TA handover can be triggered only when the preceding two conditions are metsimultaneously.

NOTE

From the perspective of the triggering conditions of TA handover, TA can be regarded as a limitation tothe size of a cell.

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Target Cell Selection

The target cell should have the highest priority in the candidate cell list after handoverpreprocessing. In addition, the target cell should meet the following conditions:

l The serving cell cannot be selected as the target cell.

l If TA Threshold of a co-site neighboring cell is lower than or equal to the TAThreshold of the serving cell, a handover to the neighboring cell is prohibited.

If the triggering conditions of TA handover are met but the candidate 2G cells are not suitable,the following operations are performed:

l If a neighboring 3G cell is available, if Inter-RAT Out BSC Handover Enable is set toYes, and if the MS supports the 2G/3G inter-RAT handover, the 2G/3G inter-RAThandover is performed.

l If no neighboring 3G cell is available, if Inter-RAT Out BSC Handover Enable is set toNo, or if the MS does not support the 2G/3G inter-RAT handover, the decision on whetherto initiate another type of emergency handover is made.

Limitations

After the TA handover is successful, the penalty is performed on the original cell. During PenaltyTime after TA HO(s), Penalty Level after TA HO is subtracted from the level of the originalcell to prevent an immediate handover back to the original cell.

BQ Handover

Bad Quality (BQ) handover is a type of emergency handover in which the system makes thedecision based on the uplink/downlink RX quality on the Um interface.

The RX quality is measured in bit error rate (BER). The BSC measures the quality of a radiolink based on the quality class in the measurement report. The probable cause of an increase inBER is that the signal power is too low or the channel interference increases.

Triggering Conditions

If BQ HO Allowed is set to Yes, the triggering conditions of BQ handover are as follows:

l The uplink RX quality is greater than or equal to the uplink RX quality threshold of theserving cell.

l The downlink RX quality is greater than or equal to the downlink RX quality threshold ofthe serving cell.

The BQ handover is triggered when either of the preceding conditions is met.

The parameters for specifying the uplink and downlink RX quality thresholds are as follows:

l For non-AMR calls, the parameter for specifying the uplink RX quality threshold is ULQual. Threshold and the parameter for specifying the downlink RX quality threshold isDL Qual. Threshold.

l For AMR FR calls, the parameter for specifying the uplink RX quality threshold isULQuaLimitAMRFR and the parameter for specifying the downlink RX quality thresholdis DLQuaLimitAMRFR.

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l For AMR HR calls, the parameter for specifying the uplink RX quality threshold isULQuaLimitAMRHR and the parameter for specifying the downlink RX qualitythreshold is DLQuaLimitAMRHR.

Target Cell SelectionThe target cell should have the highest priority in the candidate cell list after handoverpreprocessing. In addition, the target cell should meet the following conditions:

l If the target cell is a neighboring cell, the RX level of the target cell must meet the followingcondition:Filtered downlink RX level of the target cell > Filtered downlink RX level of the servingcell + Inter-cell HO Hysteresis of the serving cell configured for the neighboring cell -BQ HO Margin + 64

NOTE

In handover algorithm I, if there is only one cell in the candidate cell list and the cell is a neighboringcell, then the preceding condition need not be met.

l In handover algorithm I, if there is no neighboring cell, Intracell HO Allowed is set toYes, and the serving cell is not in the intra-cell handover penalty state, then the MS ishanded over to the serving cell. A channel with different frequency band, differentfrequency, different TRX, or different timeslot is preferred (priority: different frequencyband > different frequency > different TRX > different timeslot).

If the triggering conditions of BQ handover are met but the candidate 2G cells are not suitable,the following operations are performed:

l If a neighboring 3G cell is available, if Inter-RAT Out BSC Handover Enable is set toYes, and if the MS supports the 2G/3G inter-RAT handover, the 2G/3G inter-RAThandover is performed.

l If no neighboring 3G cell is available, if Inter-RAT Out BSC Handover Enable is set toNo, or if the MS does not support the 2G/3G inter-RAT handover, the decision on whetherto initiate another type of emergency handover is made.

LimitationsAfter the BQ handover is successful, the penalty is performed on the original cell. During PenaltyTime after BQ HO(s), Penalty Level after BQ HO is subtracted from the level of the originalcell to prevent an immediate handover back to the original cell.

Rapid Level Drop Handover

Rapid level drop handover is a type of emergency handover.

In edge handover and PBGT handover, the mean value filtering and P/N decision methods arenot responsive to short-period rapid level drop. Therefore, to solve the rapid level drop problem,the finite impact response filtering can be performed on the original RX level. This filteringmethod is responsive to the rapid level drop based on the drop slope of the original RX level.

Triggering ConditionsIf Rx_Level_Drop HO Allowed is set to Yes, the triggering conditions of rapid level drophandover are as follows:

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l Filtered uplink level < Edge HO UL RX_LEV Threshold

l A1 x C(nt) + A2 x C(nt - t) + A3 x C(nt - 2t) + … + A8 x C(nt - 7t) < BHere, A1 indicates Filter Parameter A1, A2 indicates Filter Parameter A2, A3 indicatesFilter Parameter A3, A4 indicates Filter Parameter A4, A5 indicates Filter ParameterA5, A6 indicates Filter Parameter A6, A7 indicates Filter Parameter A7, and A8indicates Filter Parameter A8.B indicates Filter Parameter B.

Target Cell SelectionThe target cell should have the highest priority in the candidate cell list after handoverpreprocessing. In addition, the target cell should meet the following conditions:

l The target cell has a higher priority than the serving cell.

l The serving cell cannot be selected as the target cell.

If the triggering conditions of rapid level drop handover are met but the candidate 2G cells arenot suitable, the following operations are performed:

l If a neighboring 3G cell is available, if Inter-RAT Out BSC Handover Enable is set toYes, and if the MS supports the 2G/3G inter-RAT handover, the 2G/3G inter-RAThandover is performed.

l If no neighboring 3G cell is available, if Inter-RAT Out BSC Handover Enable is set toNo, or if the MS does not support the 2G/3G inter-RAT handover, the decision on whetherto initiate another type of emergency handover is made.

Interference Handover

In handover algorithm I, interference handover is a type of emergency handover.

Interference handover helps protect the interfered calls and reduce the network interference. Itis applicable to scenarios with interference.

In handover algorithm I, the difference between interference handover and BQ handover is thatin BQ handover the bad quality resulting from both coverage and interference is checked. Ininterference handover, the bad quality resulting from coverage is not checked.

Triggering ConditionsIf Interference HO Allowed is set to Yes, the triggering conditions of interference handoverare as follows:

l The filtered value of uplink RX quality is greater than or equal to the specified RX qualitythreshold at the current uplink RX level.

l The filtered value of downlink RX quality is greater than or equal to the specified RXquality threshold at the current downlink RX level.

The interference handover is triggered if either of the previous conditions is met.

The parameters for specifying the uplink and downlink RX quality thresholds are as follows:

l For non-AMR FR calls, the parameter for specifying the RX quality threshold isRXQUALn, where 1 ≤ n ≤ 12.

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l For AMR FR calls, the parameters for specifying the RX quality threshold areRXQUALn (1 ≤ n ≤ 12) and RXLEVOff.

– If n = 1, the RX quality threshold is RXQUAL1.

– If 2 ≤ n ≤ 12, the RX quality threshold is RXQUALn + RXLEVOff.

Target Cell Selection

In handover algorithm I, the target cell should have the highest priority in the candidate cell list.In addition, the target cell should meet the following conditions:

l If Intracell HO Allowed is set to Yes and the intra-cell handover penalty timer expires,the serving cell can be selected as the target cell.

NOTE

When a number of consecutive intra-cell handovers occur, Forbidden time after MAX Times istriggered and the intra-cell handover is prohibited in the corresponding period.

l If the filtered level of a neighboring cell after handover penalty ≥ Inter-layer HOThreshold of the neighboring cell + Adjacent Cell Inter-layer HO Hysteresis - 64, thisneighboring cell can serve as the target cell.

If the triggering conditions of interference handover are met but the candidate 2G cells are notsuitable, the following operations need to be performed:

l If a neighboring 3G cell is available, if Inter-RAT Out BSC Handover Enable is set toYes, and if the MS supports the 2G/3G inter-RAT handover, the 2G/3G inter-RAThandover is performed.

l If no neighboring 3G cell is available, if Inter-RAT Out BSC Handover Enable is set toNo, or if the MS does not support the 2G/3G inter-RAT handover, the decision on whetherto initiate another type of emergency handover is made.

Handover Due to No Downlink Measurement Report

Handover due to no downlink measurement report is performed on the basis of the uplink quality.The purpose is to ensure the call continuity and minimize the possibility of call drops.

Handover due to no downlink measurement report is generally caused by adverse radioenvironment on the uplink. In this case, the requirements of the filtering algorithm cannot bemet, so other handover decisions cannot be performed.

Triggering Conditions

In handover algorithm I, the triggering conditions of handover due to no downlink measurementreport are as follows:

l No Dl Mr.HO Allowed is set to Yes.

l There is no downlink information in the measurement report of the call.

l The filtered value of uplink quality is greater than or equal to No Dl Mr.Ul Qual HOLimit.

l The number of lost downlink MRs is smaller than Cons.No Dl Mr.HO Allowed Limit.

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l For TCH, the number of saved MRs with uplink quality value is greater than Filter Lengthfor TCH Qual; for SDCCH, the number of saved MRs with uplink quality value is greaterthan Filter Length for SDCCH Qual.

When all the previous conditions are met, the handover due to no downlink measurement reportis triggered.

Target Cell SelectionIn handover algorithm I, the conditions for selecting the target cell are as follows:

l The ranked neighboring cells recorded in the last complete measurement report are savedas candidate cells.

l Preferably a neighboring cell is selected as the target cell.

l If no neighboring cell is available, the serving cell is selected as the target cell.

Enhanced Dual-Band Network Handover

Enhanced dual-band network handover is performed based on the traffic volume of the overlaidand underlaid cells and based on the receive level.

Enhanced dual-band network handover is classified into the following types:l Handover due to high load in the underlaid cell

l Handover due to low load in the underlaid cell

l Handover due to MS movement to the border of the overlaid cell

Triggering Conditions of Handover Due to High Load in the Underlaid CellThe triggering conditions of the handover due to high load in the underlaid cell are as follows:

l The two cells are in the enhanced dual-band network and Load HO From UL Subcell toOL Subcell Allowed is set to Yes.

l The MS supports the frequency band on which the overlaid cell operates.

l The handover due to high load in the underlaid cell is performed only on TCHs.

l The load in the underlaid cell is higher than or equal to UL Subcell General OverloadThreshold(%).

l The load in the overlaid cell is lower than Inner Cell Serious Overload Threshold(%).

l The system traffic volume is lower than or equal to Allowed Flow Control Level of ULAnd OL Subcell HO.

l The current call is within the handover margin and the receive level is greater than or equalto Incoming OL Subcell HO level Threshold(dB).

When all the preceding conditions are met, the handover due to high load in the underlaid cellis triggered.

If the load of the underlaid subcell in the cell is higher than or equal to UL Subcell SeriousOverload Threshold(%), then the handover margin is adjusted in a period of UL Subcell LoadHierarchical HO Period(s) subtracted by Modified Step Length of UL Load HO Period(s).The step length for handover margin adjustment is specified by Step Length of UL SubcellLoad HO(dB).

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Triggering Conditions of Handover Due to Low Load in the Underlaid CellThe triggering conditions of the handover due to low load in the underlaid cell are as follows:

l The load in the underlaid cell is lower than UL Subcell Lower Load Threshold(%).

l The system traffic volume is lower than or equal to Allowed Flow Control Level of ULAnd OL Subcell HO.

l The current call is within the handover margin and the receive level is greater than or equalto Outgoing OL Subcell HO level Threshold(dB).

When all the preceding conditions are met, the handover due to low load in the underlaid cell istriggered.

If the load of the underlaid subcell is lower than UL Subcell Lower Load Threshold(%) for aspecified period, then the handover margin is adjusted in a period of OL Subcell Load DiversityHO Period(s). The step length for handover margin adjustment is specified by Step Length ofOL Subcell Load HO(dB).

Triggering Conditions of Handover Due to MS Movement to the Border of theOverlaid Cell

The triggering conditions of the handover due to MS movement to the border of the overlaidcell are as follows:

l SS(s) < Thdouter

l SS(u) - SS(n) < ATCB_THRD - ATCB_HYSTHere,– SS(s): specifies the filtering compensated downlink RX level in the serving cell.

– Thdouter: specifies Outgoing OL Subcell HO level Threshold(dB).– SS(u): specifies the downlink level (power compensation is performed on the downlink

level based on the measurement) of the underlaid cell where the call is originated. If theSS(u) value cannot be obtained, you can infer that the decision of enhanced dual-bandnetwork handover is not performed and the decision condition is met by default.

– SS(n): The best neighboring cell is the one whose measured BCCH level is the highestamong neighboring cells. SS(n) is the signal level of the best neighboring cell thatoperates on the same frequency band, locates at the same layer, and has the same priorityas the underlaid cell but is not co-sited with the underlaid cell. If such a neighboringcell is not available, the value of SS(n) is -110 dBm.

– ATCB_THRD: specifies Distance Between Boundaries of UL And OL Subcells(dB).

– ATCB_HYST: specifies Distance Hysteresis Between Boundaries of UL And OLSubcells(dB).

Handover due to MS movement to the border of the overlaid cell is triggered if either ofthe preceding conditions is met.

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NOTE

l In the ATCB handover algorithm, the border between the overlaid and underlaid cells is determinedaccording to the signal strength of the serving cell and that of neighboring cells. If SS(s) = SS(n), thesystem considers that the MS is located at the border of the underlaid cell. If SS(s) - SS(n) >ATCB_THRD, the system considers that the MS is located in the coverage area of the overlaid cell.The coverage area of the overlaid cell is determined according to different networking and coverageconditions of the existing network. In addition, the overlaid cell of the serving cells and the overlaidcell of the neighboring cells will not overlap regardless of the distance between BTSs.

l The handover margin specifies the range of signal level. In the case of overlaid/underlaid load handoveron the enhanced dual-band network, the MSs whose downlink levels are within the handover marginare handed over level by level.

Target Cell SelectionThe requirements for target cell selection in the enhanced dual-band network are as follows:

l For the handover due to high load in the underlaid cell, the MS must be handed over to theoverlaid cell.

l For the handover due to low load in the underlaid cell, the MS must be handed over to theunderlaid cell.

l For the handover due to MS movement to the border of the overlaid cell, the MS is handedover to the neighboring cell that ranks first among neighboring cells. The MS should notbe handed over to the cell that ranks after the serving cell. Generally, the target cell is theunderlaid cell. The target cell can also be another neighboring cell.

LimitationsThe limitations on the handover due to high load in the underlaid cell are as follows:

l If the cell where the call is located is on an enhanced dual-band network, Attributes of ULAnd OL Subcells is set to Underlaid Subcell.

l The Load HO From UL Subcell to OL Subcell Allowed parameter should be set.

l The maximum range of the handover margin is from 63 to Incoming OL Subcell HO levelThreshold(dB). The MS with the highest receive level is handed over first.

The limitations on the handover due to low load in the underlaid cell are as follows:

l If the cell where the call is located is on the enhanced dual-band network, Attributes ofUL And OL Subcells is set to Overlaid Subcell.

l The Load HO of OL Subcell to UL Subcell Enabled parameter should be set.

l The maximum range of the handover margin is from 63 to Outgoing OL Subcell HO levelThreshold(dB). The MS with the lowest receive level is handed over first.

The limitations on the handover due to MS movement to the border of the overlaid cell are asfollows:

l If the cell where the call is located is on the enhanced dual-band network, Attributes ofUL And OL Subcells is set to Overlaid Subcell.

Impact of the Enhanced Dual-Band Network Handover on the Existing AlgorithmThe impact of the enhanced dual-band network handover on the existing algorithm is as follows:

l On the enhanced dual-band network, the MS should not be handed over to a cell in thesame underlaid/overlaid cell group when the load handovers between the overlaid cell and

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the underlaid cell (specified by Load HO From UL Subcell to OL Subcell Allowed andLoad HO of OL Subcell to UL Subcell Enabled) are allowed. This is to prevent a loadhandover of a normal cell from colliding with a load handover between the overlaid celland the underlaid cell on the network.

l The PBGT handover algorithm may cause inter-cell handover; thus, the MS should not behanded over to the cell in the same group in the case of PBGT handover between cells onthe enhanced dual-band network.

Load Handover

In the network, some cells carry heavy load whereas the overlapping upper-layer cells and theneighboring cells may carry light load. To balance the load of these cells, the load handover isrequired.

In a load handover procedure, some load in heavy-load cells is switched to light-load cells.Meanwhile, the load in neighboring cells is not switched to heavy-load cells.

Load handover can be performed between cells at different layers. Figure 1-6 shows the details.

NOTE

For details about the inter-RAT load handover, see the 2G/3G Interoperability feature.

Figure 1-6 Load handover between cells

A cell witha heavy load

A cell witha heavy load

A cell witha heavy load

A cell witha light load

A cell witha light load

A cell witha light load

A cell witha light load

To perform load sharing, increase Edge HO DL RX_LEV Threshold so that the load at theborder of a cell is switched to a neighboring cell with light load.

Whether a cell carries heavy load or light load is determined by the traffic volume in the cell,that is whether the traffic volume (generally TCH usage) in the cell exceeds the preset threshold.

l If the traffic volume in a cell is greater than Load HO Threshold(%), you can infer thatthe load in this cell is heavy. The load handover algorithm needs to be enabled.

l If the traffic volume in a cell is lower than Load Req.on Candidate Cell(%), you can inferthat the load in this cell is light and the cell can receive load from the heavy-load cells.

Load handover may lead to many handovers. Therefore, the load of the system CPU should beconsidered before load handover is performed. In other words, the system traffic volume shouldbe taken into account. In addition, to prevent too many MSs from being handed over at a time,load handover is performed step by step. In other words, the edge handover threshold is increasedon the basis of Load HO Step Level (CLS_Ramp) and Load HO Step Period (CLS_Period).

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When the increase in the edge handover threshold equals Load HO Bandwidth (CLS_Offset),the edge handover threshold is not increased any more. See Figure 1-7 for details.

Figure 1-7 Load handover

CONF_HO_RXLEV

CONF_HO_RXLEV+CLS_Ramp

CONF_HO_RXLEV+CLS_Offset

Cell A Cell B

Border of normal handoverLoad handover band

Triggering ConditionsIf Load HO Allowed is set to Yes, the triggering conditions of load handover are as follows:

l The CPU usage of the system is less than or equal to System Flux Threshold for LoadHO.

l The current load of the serving cell is greater than or equal to Load HO Threshold.

Target Cell SelectionThe conditions for selecting the target cell are as follows:

l Filtered RX level after handover penalty ≥ Inter-layer HO Threshold + Adjacent CellInter-layer HO Hysteresis - 64

l The serving cell cannot be selected as the target cell.

l If the target cell and the serving cell are in the same BSC, a load handover is performedwhen the current load of the target cell is lower than Load Req.on Candidate Cell.

l If the target cell and the serving cell are not in the same BSC, a load handover is performedwhen the load of the target cell is lower than Load Handover Load Accept Threshold(%) and Inter-BSC Load Handover Allowed is set to Yes.

ExamplesThe system assigns MSs to different load handover margins based on the downlink RX level.The load handover algorithm is used to hand over the MSs out of a cell step by step.

1. The MSs in load handover margin 1 are handed over to the neighboring cells. Load handovermargin 1 specifies the area where the downlink level ranges from Edge HO DL RX_LEVThreshold to the sum of Edge HO DL RX_LEV Threshold and Load HO Step Level.

2. After a Load HO Step Period elapses, the MSs in load handover margin 2 are handed overto the neighboring cells. The load handover margin 2 specifies the area where the downlink

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level ranges from Edge HO DL RX_LEV Threshold to the sum of Edge HO DLRX_LEV Threshold and (2 x Load HO Step Level).

3. The load handover stops when the traffic volume in the cell is less than or equal to LoadHO Threshold.

The load handover is performed step by step to prevent call drops caused by a sudden increasein CPU load or the congestion in the target cell.

Edge Handover

Edge handover is performed on the basis of receive level.

To trigger an edge handover, the receive level of the target cell should be at least one hysteresisvalue (specified by Inter-cell HO Hysteresis) greater than the receive level of the serving cell.

Triggering ConditionsIf Edge Handover Allowed is set to Yes, the triggering conditions of edge handover are asfollows:

l Either of the following conditions is met.– The filtered downlink RX level of the serving cell is lower than Edge HO DL RX_LEV

Threshold.– The filtered uplink RX level of the serving cell is lower than Edge HO UL RX_LEV

Threshold.l RX level of the neighboring cell > RX level of the serving cell + Inter-cell HO Hysteresis

An edge handover is triggered when the P/N criterion is met, that is, when the previous conditionsare met for Edge HO Valid Time(s) within Edge HO Watch Time(s).

Figure 1-8 shows the edge handover.

Figure 1-8 Edge handover

Cell 2Cell 1

-97 dBm -85 dBm

Target Cell SelectionThe target cell should have the highest priority among the candidate cells. In addition, it shouldmeet the following conditions:

l The serving cell cannot be selected as the target cell.

l After cells are ranked, the target cell must have a higher priority than the serving cell.

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A cell becomes the target cell if the previous conditions are met for Edge HO AdjCell ValidTime(s) within Edge HO AdjCell Watch Time(s).

If the triggering conditions of edge handover are met but the candidate 2G cells are not suitable,the following operations are performed:

l If a neighboring 3G cell is available, if Inter-RAT Out BSC Handover Enable is set toYes, and if the MS supports the 2G/3G inter-RAT handover, the 2G/3G inter-RAThandover is performed.

l If no neighboring 3G cell is available, if Inter-RAT Out BSC Handover Enable is set toNo, or if the MS does not support the 2G/3G inter-RAT handover, the decision on whetherto initiate another type of handover is made.

Fast-Moving Micro Cell Handover

Fast-moving micro cell handover is performed from a micro cell to a macro cell according tothe relative speed of an MS so that the number of handovers can be minimized.

Fast-moving micro cell handover applies to the following scenarios:

l If an MS is moving fast in a micro cell, it is handed over to a macro cell.

l To prevent an MS that is moving fast in a macro cell from entering a micro cell, time penaltyis performed on the micro cell so that the fast-moving MS camps on the macro cell.

Figure 1-9 shows the fast-moving micro cell handover.

Figure 1-9 Fast-moving micro cell handover

Umbrella cell

Micro cell

Triggering ConditionsIf MS Fast Moving HO Allowed is set to Yes, the handover decision procedure of fast-movingmicro cell handover is as follows:

1. When the triggering conditions of edge handover or PBGT handover are met, the fast-moving micro cell handover decision is started.

2. When the period during which the MS camps on the serving cell is shorter than MS Fast-moving Time Threshold(s), the number of cells through which the fast-moving MS passesis incremented by one.

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NOTE

The cell counted by the system must locate at a layer lower than layer 4. In other words, it must bea non-Umbrella cell.

3. When the number of cells that the MS passes in fast movement reaches MS Fast-movingWatch Cells, the fast-moving micro cell handover is triggered if the number of cells thatthe MS passes in fast movement counted by the system is greater than or equal to MS Fast-moving Valid Cells.

Target Cell SelectionIn handover algorithm I, the target cell should have the highest priority among the candidatecells. In addition, the target cell should meet the following conditions:

l The target cell must be at layer 4, that is, Umbrella cell.

l Filtered RX level of the target cell ≥ Inter-layer HO Threshold + Adjacent Cell Inter-layer HO Hysteresis - 64

LimitationsAfter the fast-moving micro cell handover is successful, the penalty is performed on all theneighboring micro cells. During Penalty Time on Fast Moving HO(s), Penalty on MS FastMoving HO is subtracted from the RX level of every neighboring micro cell.

Cell Layer and Cell PriorityWith Huawei multiband handover algorithm, a proper traffic volume distribution can be realizedamong multiple frequency bands.

Huawei multiband handover algorithm divides cells into four layers, with 16 priorities at eachlayer. The Layer of the Cell parameter specifies at which layer a cell is located. This algorithmis applicable to complex networking scenarios. Figure 1-10 shows the cell layers.

Figure 1-10 Cell layers

Layer 4

Layer 3

Layer 2

Layer 1

Macro Cell

Micro Cell

Pico Cell

Umbrella CellGSM900

GSM900GSM900

DCS1800DCS1800

GSM900GSM900 GSM900GSM900

DCS1800DCS1800

DCS1800DCS1800DCS1800

GSM900

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In Huawei multiband handover algorithm, a GSM network covering a certain area is dividedinto four layers, which are:

l Layer 4: Umbrella cell. The umbrella cells are generally GSM900 cells having the widecoverage feature. It also implements fast MS connection.

l Layer 3: Macro cell. The macro cells are generally GSM900 cells, which are commonlyused in current GSM system and serve majority of subscribers.

l Layer 2: Micro cell. The micro cells are generally DCS1800 cells having the small coveragefeature. They enable capacity expansion.

l Layer 1: Pico cell. The pico cells are generally DCS1800 cells, which are used in hot spotsand blind spots.

The cell at the lower layer has a higher priority.

Inter-Layer Handover

Inter-layer handover is a type of normal handover. It is used to enable the cells at low layers toabsorb traffic volume.

To balance the traffic volume flexibly and to meet the requirements of different networktopologies, the GSM network is divided into several layers. See Fast-Moving Micro CellHandover for details.

Triggering ConditionsIf Level HO Allowed is set to Yes, the triggering conditions of inter-layer handover are asfollows:

l The layer at which the target cell is located has a higher priority than the layer at which theserving cell is located.

l Filtered downlink RX level of the target cell ≥ Inter-layer HO Threshold + AdjacentCell Inter-layer HO Hysteresis - 64

l After cells are ranked, the target cell must have a higher priority than the serving cell.

The inter-layer handover is triggered when the P/N criterion is met, that is, the previousconditions are met for Layer HO Valid Time(s) within Layer HO Watch Time(s).

Target Cell SelectionThe requirements for target cell selection are as follows:

l The triggering conditions are met.

l The serving cell cannot be selected as the target cell.

l The target cell has the highest priority in the candidate cell list.

PBGT Handover

Power Budget (PBGT) handover is a type of normal handover.

Triggering ConditionsIf PBGT HO Allowed is set to Yes, the triggering conditions of PBGT handover are as follows:

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l The target cell and the serving cell are at the same layer and have the same priority.

l The following condition is met for PBGT Valid Time(s) within PBGT Watch Time(s):(MIN (MS_TXPWR_MAX, P) – RXLEV_DL – PWR_DIFF) – (MIN(MS_TXPWR_MAX (n), P) – RXLEV_NCELL (n) ) > PBGT_HO_MARGINHere,– RXLEV_DL: indicates the filtered downlink RX level of the serving cell.

– MS_TXPWR_MAX: indicates the maximum allowed transmit power of an MS in theserving cell.

– MS_TXPWR_MAX (n): indicates the maximum allowed transmit power of an MS inneighboring cell n.

– RxLev_NCELL (n): indicates the downlink receive level in neighboring cell n.

– PWR_DIFF: indicates the difference between the maximum downlink transmit powerin the serving cell due to power control and the actual downlink transmit power in theserving cell.

– P: indicates the maximum transmit power of an MS.

– PBGT_HO_MARGIN: indicates PBGT HO Threshold minus 64.

The PBGT handover can be triggered only when all the previous conditions are met.

Target Cell SelectionThe target cell should meet the following conditions:

l The target cell and the serving cell are at the same layer and have the same priority.

l The serving cell cannot be selected as the target cell.

l The target cell has the highest priority in the candidate cell list.

AMR Handover

The AMR handover in handover algorithm I is performed on AMR calls on the basis of radioquality indication (RQI). It consists of the AMR TCHF-TCHH handover and the AMR TCHH-TCHF handover.

The conversion formula between RQI and C/I is RQI = 2 x C/I.

Triggering Conditions of AMR TCHF-TCHH HandoverThe triggering conditions of AMR TCHF-TCHH handover are as follows:

l Intracell F-H HO Allowed is set to Yes.

l The target call is an AMR call.

l The half-rate function must be enabled in the cell where the call is initiated.

l The full-rate speech version 3 and half-rate speech version 3 must be supported by the cellwhere the call is initiated.

l The type of channel specified by the MSC during a call can be changed during a handover.

l For an AMR FR call, if AMR TCH/H Prior Allowed is set to Yes and the cell load isgreater than AMR TCH/H Prior Cell Load Threshold, the handover is allowed.

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l The call occupies the full-rate TCH. The RQI is greater than F2H HO Threshold and thecell load is greater than AMR TCH/H Prior Cell Load Threshold.

For an AMR FR call, the AMR TCHF-TCHH handover can be performed if the precedingconditions are met for Intracell F-H HO Last Time(s) within Intracell F-H HO Stat Time(s).

Triggering Conditions of AMR TCHH-TCHF HandoverThe triggering conditions of AMR TCHH-TCHF handover are as follows:

l Intracell F-H HO Allowed is set to Yes.

l The target call is an AMR call.

l The half-rate function must be enabled in the cell where the call is initiated.

l The full-rate speech version 3 and half-rate speech version 3 must be supported by the cellwhere the call is initiated.

l The type of channel specified by the MSC during a call can be changed during a handover.

l The call occupies the half-rate TCH. The RQI is smaller than H2F HO Threshold.

For an AMR HR call, the AMR TCHH-TCHF handover can be performed if the precedingconditions are met for Intracell F-H HO Last Time(s) within Intracell F-H HO Stat Time(s).

Target Cell SelectionThe AMR handover is an intra-cell handover. Therefore, only the serving cell can be selectedas the target cell.

Other Handovers

Other handovers here refer to better 3G cell handover and tight BCCH handover.

Better 3G Cell HandoverSee 2G/3G Interoperability.

Tight BCCH HandoverSee BCCH Dense Frequency Multiplexing.

1.3.5 Handover Decision Based on Handover Algorithm II

Handover decision based on handover algorithm II is made in the following order: forcedhandover, emergency handover, intra-cell handover, and inter-cell handover.

Handover decision based on handover algorithm II involves the following procedures:

l Determining whether the serving cell meets the triggering conditions

l Selecting corresponding candidate cell list for each handover type

l Performing the comprehensive decision and determining the candidate neighboring cells

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The procedure for performing comprehensive decision based on handover results anddetermining the candidate neighboring cells is as follows:

1. The BSC selects a handover type with the highest priority from all the handovers that canbe performed on each neighboring cell.The handover priority is as follows:l Forced handover, emergency handover, and interference handover have a high priority.

Figure 1-11 shows the details.

Figure 1-11 Handovers with high priority

Handover decision with high priority

Forced handover

Directed retry

Quick handover

TA handover

Interference

BQ handover

Edge handover

NOTEQuick handover is classified into frequency offset handover and quick PBGT handover.Frequency offset handover has a higher priority than quick PBGT handover.

l Intra-cell handover (excluding interference handover) and inter-cell handover have anormal priority. Figure 1-12 shows the details.

NOTE

AMR handover has the same priority as TCHF-TCHH handover.

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Figure 1-12 Handovers with normal priority

Handover decision with normal priority

Fast-moving micro cell handover

Enhanced dual-band network handover

Load handover

Better cell handover

Concentric cell handover

AMR handover

TIGHT BCCH handover

2. The BSC ranks the candidate cells according to the network characteristics adjustmentalgorithm and then generates the final candidate cell list. Every neighboring cell in thecandidate cell list has its own handover decision. Neighboring 2G cells and neighboring3G cells are ranked separately.

3. In handover algorithm II, Inter-RAT HO Preference specifies whether a neighboring 2Gor a neighboring 3G cell is preferred.

l When Inter-RAT HO Preference is set to Preference for 2G Cell:

A neighboring 2G cell is preferred. If the candidate cell list contains suitable neighboring3G cells but no suitable neighboring 2G cells, a neighboring 3G cell is selected.

l When Inter-RAT HO Preference is set to Preference for 3G Cell:

A neighboring 3G cell is preferred. If the candidate cell list contains suitable neighboring2G cells but no suitable neighboring 3G cells, a neighboring 2G cell is selected.

l When Inter-RAT HO Preference is set to Preference for 2G Cell By Threshold:

If the RX level of a candidate 2G cell is lower than or equal to HO PreferenceThreshold for 2G Cell, a neighboring 3G cell is preferred.

NOTE

When a neighboring 3G cell is preferred among the candidate cells, the priority of 3G better cell handoveris the lowest.

If the triggering conditions of emergency handover are met and there is at least one candidatecell, then the emergency handover timer Min Interval for Emerg.HOs is started. Anotheremergency handover decision can be performed only when Min Interval for Emerg.HOs timesout.

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Quick Handover

Quick handover aims to increase the handover success rate of an MS moving at a high speedand to ensure the call continuity and low call drop rate. Quick handover applies to the scenariowhere an MS moves fast along an urban backbone road, a selected route, or a high-speed railroad.

Quick Handover TypesQuick handover consists of frequency offset handover and quick PBGT handover.

l Frequency offset handoverWhether the MS is moving away from the serving cell is determined based on the frequencyoffset information provided by an MS moving at a high speed. Frequency offset handoverdecision is made according to the uplink/downlink RX level of the serving cell and the pathloss of neighboring cells.

l Quick PBGT handoverQuick PBGT handover decision is made according to the path loss of neighboring cells.

For quick handover, the handover response speed is enhanced by:

l Accurately calculating the moving speed of the MS

l Derestricting the interval between handover decisions

l Reducing the number of measurement reports for the handover decision

l Introducing the α filtering

Quick Handover PreparationThe preparation for quick handover involves the following aspects:

l Frequency offset is decoded from the measurement report.Frequency offset of the MS is obtained from the uplink measurement report that the BTSsends to the BSC.

l α filtering is performed on the measurement report.

Triggering ConditionsDuring handover decision, whether the triggering conditions of frequency offset handover aremet is determined first. When the BTS cannot send the frequency offset information or thereported frequency offset information is invalid, quick PBGT handover is triggered if otherconditions of frequency offset handover are met.

If Quick Handover Enable is set to Yes, the triggering conditions of quick handover are asfollows:

l The MS is moving away from the serving cell (the frequency offset in the measurementresult is a negative value) and the moving speed of the MS is greater than Quick MoveSpeed Threshold(m/s).

l The filtered uplink level of the serving cell is lower than Quick Handover Up TriggerLevel(dB).

l The compensated downlink level of the serving cell is lower than Quick Handover DownTrigger Level(dB).

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l The path loss of configured chain neighboring cells is lower than the specified thresholdof the path loss of the serving cell. In other words, PBGT(n) is greater than or equal to 0.

The triggering conditions of quick handover are as follows:

l If the last three conditions are met simultaneously, the decision is made as follows:

– If the first condition is met, a frequency offset handover is performed.

– If the first condition is not met, a quick PBGT handover is performed.

l If all the last three conditions are not met, quick handover is not triggered.

Target Cell Selection

The target cell must be a chain neighboring cell of the serving cell. The Chain Neighbor Cellparameter specifies whether a neighboring cell is a chain neighboring cell.

Limitations

The limitations on quick handover are as follows:

l The serving cell cannot be selected as the target cell.

l The candidate cells for quick handover must be chain neighboring cells of the serving cell.Each cell can be configured with a maximum of three chain neighboring cells.

l After a quick handover is successful, the penalty is performed on the original cell duringthe penalty time to prevent an immediate handover back to the original cell. The penaltytime and penalty value are specified by Quick Handover Punish Time(s) and QuickHandover Punish Value(dB) respectively.

TA Handover

Timing Advance (TA) handover is a type of emergency handover. The TA handover decisionis made according to the TA value reported by the MS.

The TA value of a normal cell ranges from 0 to 63 and that of an extended cell ranges from 0 to229. The TA can be stepped up or down in steps of 553.5 m. The TA value of 63 correspondsto a distance of 35 km.

Triggering Conditions

TA handover is triggered when the following conditions are met:

l TA HO Allowed is set to Yes.

l Filtered TA value in the measurement report provided by the MS is greater than or equalto TA Threshold.

The TA handover can be triggered only when the preceding two conditions are metsimultaneously.

NOTE

From the perspective of the triggering conditions of TA handover, TA can be regarded as a limitation tothe size of a cell.

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Target Cell Selection

The target cell should have the highest priority in the candidate cell list after handoverpreprocessing. In addition, the target cell should meet the following limitations:

l The serving cell cannot be selected as the target cell.

l If TA Threshold of a co-site neighboring cell is lower than or equal to the TAThreshold of the serving cell, a handover to the neighboring cell is prohibited.

l In handover algorithm II, a cell becomes the target cell for TA handover if the previousconditions are met for TA HO Valid Time(0.5s) within TA HO Watch Time(0.5s).

If the triggering conditions of TA handover are met but the candidate 2G cells are not suitable,the following operations are performed:

l If a neighboring 3G cell is available, if Inter-RAT Out BSC Handover Enable is set toYes, and if the MS supports the 2G/3G inter-RAT handover, the 2G/3G inter-RAThandover is performed.

l If no neighboring 3G cell is available, if Inter-RAT Out BSC Handover Enable is set toNo, or if the MS does not support the 2G/3G inter-RAT handover, the decision on whetherto initiate another type of emergency handover is made.

Limitations

After the TA handover is successful, the penalty is performed on the original cell. During PenaltyTime after TA HO(s), Penalty Level after TA HO is subtracted from the level of the originalcell to prevent an immediate handover back to the original cell.

BQ Handover

Bad Quality (BQ) handover is a type of emergency handover in which the system makes thedecision based on the uplink/downlink RX quality on the Um interface.

RX quality is represented by bit error rate (BER). The BSC measures the quality of a radio linkbased on the quality class in the measurement report. The probable cause of an increase in BERis that the signal power is too low or the channel interference increases.

Triggering Conditions

If BQ HO Allowed is set to Yes, the triggering conditions of BQ handover are as follows:

l The uplink RX quality is greater than or equal to the uplink RX quality threshold of theserving cell.

l The downlink RX quality is greater than or equal to the downlink RX quality threshold ofthe serving cell.

The BQ handover is triggered when either of the preceding conditions is met.

The parameters for specifying the uplink and downlink RX quality thresholds are as follows:

l For non-AMR calls, the parameter for specifying the uplink RX quality threshold is ULQual. Threshold and the parameter for specifying the downlink RX quality threshold isDL Qual. Threshold.

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l For AMR FR calls, the parameter for specifying the uplink RX quality threshold isULQuaLimitAMRFR and the parameter for specifying the downlink RX quality thresholdis DLQuaLimitAMRFR.

l For AMR HR calls, the parameter for specifying the uplink RX quality threshold isULQuaLimitAMRHR and the parameter for specifying the downlink RX qualitythreshold is DLQuaLimitAMRHR.

Target Cell SelectionThe target cell should have the highest priority in the candidate cell list after handoverpreprocessing. In addition, the target cell should meet the following conditions:

l In handover algorithm II, the serving cell cannot be selected as the target cell.

l The RX level of target cell must meet the following conditions:– The serving cell and the target cell work in the same frequency.

Filtered downlink RX level of the target cell > Filtered downlink RX level of the servingcell + Inter-cell HO Hysteresis of the serving cell configured for the neighboring cell- BQ HO Margin + 64

– The serving cell works in GSM900 and the target cell works in DCS1800.Filtered downlink RX level of the target cell ≥ Inter-layer HO Threshold + (Inter-layer HO Hysteresis - 64).

– The serving cell works in DCS1800 and the target cell works in GSM900.There is no constraint on the target cell in this condition.

l In handover algorithm II, a cell becomes the target cell for BQ handover if the previousconditions are met for BQ HO Valid Time(0.5s) within BQ HO Watch Time(0.5s).

If the triggering conditions of BQ handover are met but the candidate 2G cells are not suitable,the following operations are performed:

l If a neighboring 3G cell is available, if Inter-RAT Out BSC Handover Enable is set toYes, and if the MS supports the 2G/3G inter-RAT handover, the 2G/3G inter-RAThandover is performed.

l If no neighboring 3G cell is available, if Inter-RAT Out BSC Handover Enable is set toNo, or if the MS does not support the 2G/3G inter-RAT handover, the decision on whetherto initiate another type of emergency handover is made.

LimitationsAfter the BQ handover is successful, the penalty is performed on the original cell. During PenaltyTime after BQ HO(s), Penalty Level after BQ HO is subtracted from the level of the originalcell to prevent an immediate handover back to the original cell.

Interference Handover

Interference handover is a type of intra-cell handover in handover algorithm II.

Interference handover helps protect the interfered calls and reduce the network interference. Itis applicable to scenarios with interference.

In handover algorithm II, the BQ handover is a type of emergency handover and the interferencehandover is a type of intra-cell handover.

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Triggering ConditionsIf Intracell HO Allowed is set to Yes and Interference HO Allowed is set to Yes, the triggeringconditions of interference handover are as follows:

l The filtered value of uplink RX quality is greater than or equal to the specified RX qualitythreshold at the current uplink RX level.

l The filtered value of downlink RX quality is greater than or equal to the specified RXquality threshold at the current downlink RX level.

In handover algorithm II, the interference handover is triggered when the previous conditionsare met for Interfere HO Valid Time(0.5s) within Interfere HO Static Time(0.5s).

The parameters for specifying the uplink and downlink RX quality thresholds are as follows:

l For non-AMR FR calls, the parameter for specifying the RX quality threshold isRXQUALn, where 1 ≤ n ≤ 12.

l For AMR FR calls, the parameters for specifying the RX quality threshold areRXQUALn (1 ≤ n ≤ 12) and RXLEVOff.– If n = 1, the RX quality threshold is RXQUAL1.

– If 2 ≤ n ≤ 12, the RX quality threshold is RXQUALn + RXLEVOff.

Target Cell SelectionIn handover algorithm II, only the serving cell can be selected as the target cell.

LimitationsIn handover algorithm II, if an interference handover is initiated, it cannot be initiated againwithin Penalty Time on Interfere HO regardless of whether the handover is successful.

Handover Due to No Downlink Measurement Report

Handover due to no downlink measurement report is performed on the basis of the uplink quality.The purpose is to ensure the call continuity and minimize the possibility of call drops.

Handover due to no downlink measurement report is generally caused by adverse radioenvironment on the uplink. In this case, the requirements of the filtering algorithm cannot bemet, so other handover decisions cannot be performed.

Triggering ConditionsIn handover algorithm II, the triggering conditions of handover due to no downlink measurementreport are as follows:

l No Dl Mr.HO Allowed is set to Yes.

l There is no downlink information in the measurement report of the call.

l The number of lost downlink MRs is smaller than Cons.No Dl Mr.HO Allowed Limit.

l For TCH, the number of saved MRs with uplink quality value is greater than Filter Lengthfor TCH Qual; for SDCCH, the number of saved MRs with uplink quality value is greaterthan Filter Length for SDCCH Qual.

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l The filtered value of uplink RX quality is greater than or equal to UL Qual. Threshold.– For AMR FR calls, the corresponding parameter is ULQuaLimitAMRFR.

– For AMR HR calls, the corresponding parameter is ULQuaLimitAMRHR.

When all the previous conditions are met, the handover due to no downlink measurement reportis triggered.

Target Cell SelectionIn handover algorithm II, the conditions for selecting the target cell are as follows:

l The ranked neighboring cells recorded in the last complete measurement report are savedas candidate cells.

l Only a neighboring cell can serve as the target cell.

l RX level in neighboring cell > Filtered RX level in serving cell + Inter-cell HOHysteresis - BQ HO Margin + 64

l A neighboring cell serves as the target cell if the previous conditions are met for UL BQHO Last Time(0.5s) within UL BQ HO Static Time(0.5s).

Enhanced Dual-Band Network Handover

Enhanced dual-band network handover is performed based on the traffic volume of the overlaidand underlaid cells and based on the receive level.

Enhanced dual-band network handover is classified into the following types:l Handover due to high load in the underlaid cell

l Handover due to low load in the underlaid cell

l Handover due to MS movement to the border of the overlaid cell

Triggering Conditions of Handover Due to High Load in the Underlaid CellThe triggering conditions of the handover due to high load in the underlaid cell are as follows:

l The two cells are in the enhanced dual-band network and Load HO From UL Subcell toOL Subcell Allowed is set to Yes.

l The MS supports the frequency band on which the overlaid cell operates.

l The handover due to high load in the underlaid cell is performed only on TCHs.

l The load in the underlaid cell is higher than or equal to UL Subcell General OverloadThreshold(%).

l The load in the overlaid cell is lower than Inner Cell Serious OverLoad Threshold(%).l The system traffic volume is lower than or equal to Allowed Flow Control Level of UL

And OL Subcell HO.l The current call is within the handover margin and the receive level is greater than or equal

to Incoming OL Subcell HO level Threshold(dB).

When all the preceding conditions are met, the handover due to high load in the underlaid cellis triggered.

If the load of the underlaid subcell in the cell is higher than or equal to UL Subcell SeriousOverload Threshold(%), then the handover margin is adjusted in a period of UL Subcell Load

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Hierarchical HO Period(s) subtracted by Modified Step Length of UL Load HO Period(s).The step length for handover margin adjustment is specified by Step Length of UL SubcellLoad HO(dB).

Triggering Conditions of Handover Due to Low Load in the Underlaid Cell

The triggering conditions of the handover due to low load in the underlaid cell are as follows:

l The load in the underlaid cell is lower than UL Subcell Lower Load Threshold(%).

l The system traffic volume is lower than or equal to Allowed Flow Control Level of ULAnd OL Subcell HO.

l The current call is within the handover margin and the receive level is greater than or equalto Outgoing OL Subcell HO level Threshold(dB).

When all the preceding conditions are met, the handover due to low load in the underlaid cell istriggered.

If the load of the underlaid subcell is lower than UL Subcell Lower Load Threshold(%) for aspecified period, then the handover margin is adjusted in a period of OL Subcell Load DiversityHO Period(s). The step length for handover margin adjustment is specified by Step Length ofOL Subcell Load HO(dB).

Triggering Conditions of Handover Due to MS Movement to the Border of theOverlaid Cell

The triggering conditions of the handover due to MS movement to the border of the overlaidcell are as follows:

l SS(s) < Thdouter

l SS(u) - SS(n) < ATCB_THRD - ATCB_HYST

Here,

– SS(s): specifies the filtering compensated downlink RX level in the serving cell.

– Thdouter: specifies Outgoing OL Subcell HO level Threshold(dB).

– SS(u): specifies the downlink level (power compensation is performed on the downlinklevel based on the measurement) of the underlaid cell where the call is originated. If theSS(u) value cannot be obtained, you can infer that the decision of enhanced dual-bandnetwork handover is not performed and the decision condition is met by default.

– SS(n): The best neighboring cell is the one whose measured BCCH level is the highestamong neighboring cells. SS(n) is the signal level of the best neighboring cell thatoperates on the same frequency band, locates at the same layer, and has the same priorityas the underlaid cell but is not co-sited with the underlaid cell. If such a neighboringcell is not available, the value of SS(n) is -110 dBm.

– ATCB_THRD: specifies Distance Between Boundaries of UL And OL Subcells(dB).

– ATCB_HYST: specifies Distance Hysteresis Between Boundaries of UL And OLSubcells(dB).

Handover due to MS movement to the border of the overlaid cell is triggered if either ofthe preceding conditions is met.

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NOTE

l In the ATCB handover algorithm, the border between the overlaid and underlaid cells is determinedaccording to the signal strength of the serving cell and that of neighboring cells. If SS(s) = SS(n), thesystem considers that the MS is located at the border of the underlaid cell. If SS(s) - SS(n) >ATCB_THRD, the system considers that the MS is located in the coverage area of the overlaid cell.The coverage area of the overlaid cell is determined according to different networking and coverageconditions of the existing network. In addition, the overlaid cell of the serving cells and the overlaidcell of the neighboring cells will not overlap regardless of the distance between BTSs.

l The handover margin specifies the range of signal level. In the case of overlaid/underlaid load handoveron the enhanced dual-band network, the MSs whose downlink levels are within the handover marginare handed over level by level.

Target Cell SelectionThe requirements for target cell selection in the enhanced dual-band network are as follows:

l For the handover due to high load in the underlaid cell, the MS must be handed over to theoverlaid cell.

l For the handover due to low load in the underlaid cell, the MS must be handed over to theunderlaid cell.

l For the handover due to MS movement in the overlaid subcell, the MS must be handedover to the underlaid cell.

LimitationsThe limitations on the handover due to high load in the underlaid cell are as follows:

l If the cell where the call is located is on an enhanced dual-band network, Attributes of ULAnd OL Subcells is set to Underlaid Subcell.

l The Load HO From UL Subcell to OL Subcell Allowed parameter should be set.

l The maximum range of the handover margin is from 63 to Incoming OL Subcell HO levelThreshold(dB). The MS with the highest receive level is handed over first.

The limitations on the handover due to low load in the underlaid cell are as follows:

l If the cell where the call is located is on the enhanced dual-band network, Attributes ofUL And OL Subcells is set to Overlaid Subcell.

l The Load HO of OL Subcell to UL Subcell Enabled parameter should be set.

l The maximum range of the handover margin is from 63 to Outgoing OL Subcell HO levelThreshold(dB). The MS with the lowest receive level is handed over first.

The limitations on the handover due to MS movement to the border of the overlaid cell are asfollows:

l If the cell where the call is located is on the enhanced dual-band network, Attributes ofUL And OL Subcells is set to Overlaid Subcell.

Impact of the Enhanced Dual-Band Network Handover on the Existing AlgorithmThe impact of the enhanced dual-band network handover on the existing algorithm is as follows:

On the enhanced dual-band network, the MS should not be handed over to a cell in the sameunderlaid/overlaid cell group when the load handovers between the overlaid cell and theunderlaid cell (specified by Load HO From UL Subcell to OL Subcell Allowed and Load HO

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of OL Subcell to UL Subcell Enabled) are allowed. This is to prevent a load handover of anormal cell from colliding with a load handover between the overlaid cell and the underlaid cellon the network.

Load Handover

In handover algorithm II, load handover is not decided independently.

In handover algorithm II, the load handover decision is made in network adjustment phase. Theselection of target cell should be processed by the better cell handover. That is, the load handoveris triggered when the triggering conditions of load handover and better cell handover are metsimultaneously.

See Load Handover for the triggering conditions of load handover. See Better CellHandover for the triggering conditions of better cell handover.

Edge Handover

Edge handover is performed on the basis of receive level.

To trigger an edge handover, the receive level of the target cell should be at least one hysteresisvalue (specified by Inter-cell HO Hysteresis) greater than the receive level of the serving cell.

Triggering ConditionsIf Edge Handover Allowed is set to Yes, the triggering conditions of edge handover are asfollows:

l Either of the following conditions is met.– The filtered downlink RX level of the serving cell is lower than Edge HO DL RX_LEV

Threshold.– The filtered uplink RX level of the serving cell is lower than Edge HO UL RX_LEV

Threshold.l RX level of the neighboring cell > RX level of the serving cell + Inter-cell HO Hysteresis

An edge handover is triggered when the P/N criterion is met, that is, when the previous conditionsare met for Edge HO Valid Time(s) within Edge HO Watch Time(s).

Figure 1-13 shows the edge handover.

Figure 1-13 Edge handover

Cell 2Cell 1

-97 dBm -85 dBm

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Target Cell Selection

The target cell should have the highest priority among the candidate cells. In addition, it shouldmeet the following conditions:

l The serving cell cannot be selected as the target cell.

l After cells are ranked, the target cell must have a higher priority than the serving cell.

A cell becomes the target cell if the previous conditions are met for Edge HO AdjCell ValidTime(s) within Edge HO AdjCell Watch Time(s).

If the triggering conditions of edge handover are met but the candidate 2G cells are not suitable,the following operations are performed:

l If a neighboring 3G cell is available, if Inter-RAT Out BSC Handover Enable is set toYes, and if the MS supports the 2G/3G inter-RAT handover, the 2G/3G inter-RAThandover is performed.

l If no neighboring 3G cell is available, if Inter-RAT Out BSC Handover Enable is set toNo, or if the MS does not support the 2G/3G inter-RAT handover, the decision on whetherto initiate another type of handover is made.

Fast-Moving Micro Cell Handover

Fast-moving micro cell handover is performed from a micro cell to a macro cell according tothe relative speed of an MS so that the number of handovers can be minimized.

Fast-moving micro cell handover applies to the following scenarios:

l If an MS is moving fast in a micro cell, it is handed over to a macro cell.

l To prevent an MS that is moving fast in a macro cell from entering a micro cell, time penaltyis performed on the micro cell so that the fast-moving MS camps on the macro cell.

Figure 1-14 shows the fast-moving micro cell handover.

Figure 1-14 Fast-moving micro cell handover

Umbrella cell

Micro cell

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Triggering ConditionsIf MS Fast Moving HO Allowed is set to Yes, the handover decision procedure of fast-movingmicro cell handover is as follows:

1. When the triggering conditions of edge handover or PBGT handover are met, the fast-moving micro cell handover decision is started.

2. When the period during which the MS camps on the serving cell is shorter than MS Fast-moving Time Threshold(s), the number of cells through which the fast-moving MS passesis incremented by one.

NOTE

The cells counted by the system must locate at a layer lower than layer 4. In other words, they mustbe non-Umbrella cells.

3. When the number of cells that the MS passes in fast movement reaches MS Fast-movingWatch Cells, the fast-moving micro cell handover is triggered if the number of cells thatthe MS passes in fast movement counted by the system is greater than or equal to MS Fast-moving Valid Cells.

Target Cell SelectionIn handover algorithm II, the target cell should have the highest priority among the candidatecells. In addition, the target cell should meet the following conditions:

l The target cell must be at layer 4, that is, Umbrella cell.

l Filtered RX level of the target cell ≥ Inter-layer HO Threshold + Adjacent Cell Inter-layer HO Hysteresis - 64

l A neighboring cell serves as the target cell if the previous conditions are met for HCS HOValid Time(0.5s) within HCS HO Watch Time(0.5s).

LimitationsAfter the fast-moving micro cell handover is successful, the penalty is performed on all theneighboring micro cells. During Penalty Time on Fast Moving HO(s), Penalty on MS FastMoving HO is subtracted from the RX level of every neighboring micro cell.

Cell Layer and Cell PriorityThrough Huawei multiband handover algorithm, a proper traffic volume distribution can berealized among multiple frequency bands.

Huawei multiband handover algorithm divides cells into four layers, with 16 priorities at eachlayer. The Layer of the Cell parameter specifies at which layer a cell is located. This algorithmis applicable to complex networking scenarios. Figure 1-15 shows the cell layers.

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Figure 1-15 Cell layers

Layer 4

Layer 3

Layer 2

Layer 1

Macro Cell

Micro Cell

Pico Cell

Umbrella CellGSM900

GSM900GSM900

DCS1800DCS1800

GSM900GSM900 GSM900GSM900

DCS1800DCS1800

DCS1800DCS1800DCS1800

GSM900

In Huawei multiband handover algorithm, a GSM network covering a certain area is dividedinto four layers, which are:

l Layer 4: Umbrella cell. The umbrella cells are generally GSM900 cells having the widecoverage feature. It also implements fast MS connection.

l Layer 3: Macro cell. The macro cells are generally GSM900 cells, which are commonlyused in current GSM system and serve majority of subscribers.

l Layer 2: Micro cell. The micro cells are generally DCS1800 cells having the small coveragefeature. They enable capacity expansion.

l Layer 1: Pico cell. The pico cells are generally DCS1800 cells, which are used in hot spotsand blind spots.

The cell at the lower layer has a higher priority.

Better Cell Handover

Better cell handover is optimized from inter-layer handover and PBGT handover in handoveralgorithm I, and performs handover decision based on handover algorithm II.

Triggering Conditions

If Better Cell Handover Enable is set to Yes, the triggering conditions of better cell handoverare as follows:

l If Pathloss Ho. Enable is set to Yes, the serving cell and the target cell are ranked basedon the path loss; if Pathloss Ho. Enable is set to No, pathloss is not taken into considerationduring the sorting of serving cells and target cells.

l After cells are ranked, the target cell must have a higher priority than the serving cell.

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l The target cell meets the preceding conditions for Better Cell HO Valid Time(s) withinBetter Cell HO Watch Time(s).

Target Cell Selection

The requirements for target cell selection are as follows:

l The serving cell cannot be selected as the target cell.

l The target cell has the highest priority in the candidate cell list.

Handover Between a Full-Rate TCH and a Half-Rate TCH

Handover between a full-rate TCH and a half-rate TCH performs decision based on handoveralgorithm II.

Types of handover between a full-rate TCH and a half-rate TCH are as follows:

l AMR TCHF-TCHH handover and non-AMR TCHF-TCHH handover

The purpose is to absorb more MSs and to reduce the cell congestion if the cell load is high.

l AMR TCHH-TCHF handover and non-AMR TCHH-TCHF handover

The purpose is to improve the speech quality of the call if the cell load is low.

Triggering Conditions of AMR TCHF-TCHH Handover

If the IntraCell AMR TCHF-TCHH Ho Allowed is set to Yes, the triggering conditions ofAMR TCHF-TCHH handover are as follows:

l Speech Version used by the call is full-rate speech version 3.

l Downlink path loss of the call ≤ IntraCell AMR TCHF-TCHH Ho PathlossThreshold + path loss handover margin

l ATCB of the call ≥ IntraCell AMR TCHF-TCHH Ho ATCB Threshold – ATCBhandover margin

l Uplink signal quality of the call ≤ IntraCell AMR TCHF-TCHH Ho Qual. Threshold

l Downlink signal quality of the call ≤ IntraCell AMR TCHF-TCHH Ho Qual.Threshold

l The preceding conditions are met for IntraCell TCHF-TCHH Ho Last Time(s) withinIntraCell TCHF-TCHH Ho Stat Time(s).

Triggering Conditions of Non-AMR TCHF-TCHH Handover

If the IntraCell Non-AMR TCHF-TCHH Ho Allowed is set to Yes, the triggering conditionsof non-AMR TCHF-TCHH handover are as follows:

l Speech Version used by the call is full-rate speech version 1 or full-rate speech version 2.

l Downlink path loss of the call ≤ IntraCell Non-AMR TCHF-TCHH Ho PathlossThreshold + path loss handover margin

l ATCB of the call ≥ IntraCell Non-AMR TCHF-TCHH Ho ATCB Threshold – ATCBhandover margin

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l Uplink signal quality of the call ≤ IntraCell Non-AMR TCHF-TCHH Ho Qual.Threshold

l Downlink signal quality ≤ IntraCell Non-AMR TCHF-TCHH Ho Qual. Threshold

l The preceding conditions are met for IntraCell TCHF-TCHH Ho Last Time(s) withinIntraCell TCHF-TCHH Ho Stat Time(s).

Triggering Conditions of AMR TCHH-TCHF Handover

If IntraCell AMR TCHF-TCHH Ho Allowed is set to Yes or IntraCell AMR TCHH-TCHFQual Ho Allowed is set to Yes, the triggering conditions of AMR TCHF-TCHH handover areas follows:

l Speech Version used by the call is half-rate speech version 3.

l Downlink path loss ≤ IntraCell AMR TCHH-TCHF Ho Pathloss Threshold

l ATCB of the call ≤ IntraCell AMR TCHH-TCHF Ho ATCB Threshold

l Uplink signal quality ≥ IntraCell AMR TCHH-TCHF Ho Qual. Threshold

l Downlink signal quality of the call ≥ IntraCell AMR TCHH-TCHF Ho Qual.Threshold

l The AMR TCHH-TCHF handover is triggered if either of the preceding conditions is metfor IntraCell TCHH-TCHF Ho Last Time(s) within IntraCell TCHH-TCHF Ho StatTime(s) and Speech Version is half-rate speech version 3.

Triggering Conditions of Non-AMR TCHH-TCHF Handover

If IntraCell Non-AMR TCHF-TCHH Ho Allowed is set to Yes or IntraCell Non-AMRTCHH-TCHF Qual. Ho Allowed is set to Yes, the triggering conditions of non-AMR TCHF-TCHH handover are as follows:

l Speech Version used by the call is half-rate speech version 1.

l Downlink path loss of the call ≤ IntraCell Non-AMR TCHH-TCHF Ho PathlossThreshold

l ATCB of the call ≤ IntraCell Non-AMR TCHH-TCHF Ho ATCB Threshold

l Uplink signal quality of the call ≥ IntraCell Non-AMR TCHH-TCHF Ho Qual.Threshold

l Downlink signal quality of the call ≥ IntraCell Non-AMR TCHH-TCHF Ho Qual.Threshold

l The non-AMR TCHH-TCHF handover is triggered if either of the preceding conditions ismet for IntraCell TCHH-TCHF Ho Last Time(s) within IntraCell TCHH-TCHF HoStat Time(s) and Speech Version is half-rate speech version 1.

Target Cell Selection

Only the serving cell can be selected as the target cell of the TCHF-TCHH handover.

Other Handovers

Other handovers here refer to better 3G cell handover and tight BCCH handover.

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Better 3G Cell HandoverSee 2G/3G Interoperability.

Tight BCCH HandoverSee BCCH Dense Frequency Multiplexing.

1.4 Maintenance Information

ParametersTable 1-4 lists the parameters related to handover.

Table 1-4 Parameters related to handover

Name Effective Level

HO Control Switch Cell

Power boost before HO enabled or not Cell

MR.Preprocessing Cell

Transfer Original MR Cell

Transfer BS/MS Power Class Cell

Sent Freq.of preprocessed MR Cell

Measurement Report Type Cell

DtxMeasUsed Cell

Allowed M.R Number Lost Cell

Filter Length for SDCCH Level. Cell

Filter Length for TCH Level. Cell

Filter Length for SDCCH Qual Cell

Filter Length for TCH Qual Cell

Filter Length for TA Cell

TA Filter Length for SDCCH Level Cell

Filter Length for Ncell RX_LEV Cell

NCell Filter Length for SDCCH Level Cell

Quick Handover Punish Time(s) Cell

Quick Handover Punish Value(dB) Cell

Penalty Time after TA HO(s) Cell

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Name Effective Level

Penalty Time after BQ HO(s) Cell

Penalty Value on Load HO Cell

Penalty Level after TA HO Cell

Penalty Level after BQ HO Cell

Penalty on Fast Moving Handover Cell

Penalty Time on Fast Moving HO(s) Cell

Penalty Time after AMR TCHF-H HO Fail(s) Cell

Penalty Time on Interfere HO Cell

Penalty Time of UtoO HO(s) Cell

Inter UL And OL Subcells HO Penalty Time(s) Cell

Penalty Level after HO Fail Cell

UmPenaltyTimer Cell

RscPenaltyTimer Cell

CfgPenaltyTimer Cell

Penalty Time after OtoU HO Fail(s) Cell

Penalty Time after UtoO HO Fail(s) Cell

Inter-BSC SDCCH HO ALLowed Cell

Min DL level on Candidate Cell Cell

Min Access Level Offset Cell

Min UP Power on HO Candidate Cell Cell

Min Ec/No Threshold Cell

FDD REP QUANT Cell

Min RSCP Threshold Cell

Penalty Time on Load HO Cell

Directed Retry Permitted Cell

Inter-RAT HO Preference Cell

Min Interval for Emerg.HOs Cell

HO Preference Threshold for 2G Cell Cell

Quick Handover Enable Cell

Quick Move Speed Threshold(m/s) Cell

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Name Effective Level

Quick Handover Up Trigger Level(dB) Cell

Quick Handover Down Trigger Level(dB) Cell

Chain Neighbor Cell Cell

TA HO Allowed Cell

TA Threshold Cell

Inter-RAT In BSC Handover Enable Cell

Inter-RAT Cell Reselection Enable Cell

BQ HO Allowed Cell

UL Qual. Threshold Cell

DL Qual. Threshold Cell

ULQuaLimitAMRFR Cell

DLQuaLimitAMRFR Cell

ULQuaLimitAMRHR Cell

DLQuaLimitAMRHR Cell

Inter-cell HO Hysteresis Cell

BQ HO Margin Cell

Intracell HO Allowed Cell

Rx_Level_Drop HO Allowed Cell

Edge HO UL RX_LEV Threshold Cell

Filter Parameter A1 Cell

Filter Parameter A2 Cell

Filter Parameter A3 Cell

Filter Parameter A4 Cell

Filter Parameter A5 Cell

Filter Parameter A6 Cell

Filter Parameter A7 Cell

Filter Parameter A8 Cell

Filter Parameter B Cell

Interference HO Allowed Cell

RXQUAL1 Cell

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Name Effective Level

RXQUAL2 Cell

RXQUAL3 Cell

RXQUAL4 Cell

RXQUAL5 Cell

RXQUAL6 Cell

RXQUAL7 Cell

RXQUAL8 Cell

RXQUAL9 Cell

RXQUAL10 Cell

RXQUAL11 Cell

RXQUAL12 Cell

RXLEVOff Cell

Forbidden time after MAX Times Cell

Inter-layer HO Threshold Cell

Inter-cell HO Hysteresis Cell

No Dl Mr.HO Allowed Cell

No Dl Mr.Ul Qual HO Limit Cell

Cons.No Dl Mr.HO Allowed Limit Cell

Load HO From UL Subcell to OL Subcell Allowed Cell

UL Subcell General Overload Threshold(%) Cell

Inner Cell Serious OverLoad Threshold(%) Cell

Allowed Flow Control Level of UL And OL Subcell HO Cell

UL Subcell Serious Overload Threshold(%) Cell

UL Subcell Load Hierarchical HO Period(s) Cell

Modified Step Length of UL Load HO Period(s) Cell

Step Length of UL Subcell Load HO(dB) Cell

UL Subcell Lower Load Threshold(%) Cell

Allowed Flow Control Level of UL And OL Subcell HO Cell

Outgoing OL Subcell HO level Threshold(dB) Cell

Distance Between Boundaries of UL And OL Subcells(dB) Cell

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Name Effective Level

Distance Hysteresis Between Boundaries of UL And OL Subcells(dB) Cell

Incoming OL Subcell HO level Threshold(dB) Cell

Load HO of OL Subcell to UL Subcell Enabled Cell

HW_Concentric Attribute Cell

Edge HO DL RX_LEV Threshold Cell

Load HO Threshold(%) Cell

Load Req.on Candidate Cell(%) Cell

Load HO Step Level Cell

Load HO Bandwidth Cell

Load HO Allowed Cell

System Flux Threshold for Load HO Cell

Edge Handover Allowed Cell

Edge HO Watch Time(s) Cell

Edge HO Valid Time(s) Cell

MS Fast Moving HO Allowed Cell

MS Fast-moving Time Threshold Cell

MS Fast-moving Watch Cells Cell

MS Fast-moving Valid Cells Cell

Layer of the Cell Cell

Level HO Allowed Cell

Layer HO Watch Time(s) Cell

Layer HO Valid Time(s) Cell

PBGT HO Allowed Cell

PBGT Watch Time(s) Cell

PBGT Valid Time(s) Cell

PBGT HO Threshold Cell

Penalty Allowed Cell

Penalty Time on Interfere HO Cell

TA HO Watch Time(Num of MR)(0.5s) Cell

TA HO Valid Time(0.5s) Cell

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Name Effective Level

BQ HO Watch Time(0.5s) Cell

BQ HO Valid Time(0.5s) Cell

Interfere HO Static Time(0.5s) Cell

Interfere HO Valid Time(0.5s) Cell

UL BQ HO Static Time(0.5s) Cell

UL BQ HO Last Time(0.5s) Cell

HCS HO Watch Time(0.5s) Cell

HCS HO Valid Time(0.5s) Cell

Better Cell Handover Enable Cell

Better Cell HO Watch Time(s) Cell

Pathloss Ho. Enable Cell

Better Cell HO Valid Time(s) Cell

IntraCell AMR TCHF-TCHH Ho Allowed Cell

IntraCell AMR TCHF-TCHH Ho Pathloss Threshold Cell

IntraCell AMR TCHF-TCHH Ho ATCB Threshold Cell

IntraCell AMR TCHF-TCHH Ho Qual. Threshold Cell

IntraCell TCHF-TCHH Ho Stat Time(s) Cell

IntraCell TCHF-TCHH Ho Last Time(s) Cell

IntraCell Non-AMR TCHF-TCHH Ho Allowed Cell

IntraCell Non-AMR TCHF-TCHH Ho Pathloss Threshold Cell

IntraCell Non-AMR TCHF-TCHH Ho ATCB Threshold Cell

IntraCell Non-AMR TCHF-TCHH Ho Qual. Threshold Cell

IntraCell AMR TCHH-TCHF Qual Ho Allowed Cell

IntraCell AMR TCHH-TCHF Ho Pathloss Threshold Cell

IntraCell AMR TCHH-TCHF Ho ATCB Threshold Cell

IntraCell AMR TCHH-TCHF Ho Qual. Threshold Cell

IntraCell TCHH-TCHF Ho Stat Time(s) Cell

IntraCell TCHH-TCHF Ho Last Time(s) Cell

IntraCell Non-AMR TCHH-TCHF Qual. Ho Allowed Cell

IntraCell Non-AMR TCHH-TCHF Ho Pathloss Threshold Cell

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Name Effective Level

IntraCell Non-AMR TCHH-TCHF Ho ATCB Threshold Cell

IntraCell Non-AMR TCHH-TCHF Ho Qual. Threshold Cell

Intracell F-H HO Allowed Cell

AMR TCH/H Prior Allowed Cell

AMR TCH/H Prior Cell Load Threshold Cell

F2H HO Threshold Cell

Intracell F-H HO Last Time(s) Cell

Intracell F-H HO Stat Time(s) Cell

H2F HO Threshold Cell

Attributes of UL And OL Subcells Cell

OL Subcell Load Diversity HO Period(s) Cell

Step Length of OL Subcell Load HO(dB) Cell

Inter-layer HO Hysteresis Cell

Inter-BSC Load Handover Allowed Cell

Counters

Table 1-5 lists the counters related to handover.

Table 1-5 Counters related to handover

Counter ID Counter Name

H3000 Internal Intra-Cell Handover Requests (SDCCH)

H3009 Internal Intra-Cell Handover Requests (TCH)

H3010 Internal Intra-Cell Handover Commands (SDCCH)

H3017 Internal Intra-Cell Handover Commands (TCHF)

H3018 Internal Intra-Cell Handover Commands (TCHH)

H3020 Failed Internal Intra-Cell Handovers (SDCCH)

H3029 Failed Internal Intra-Cell Handovers (TCH)

H3020A Failed Internal Intra-Cell Handovers (ChannelUnavailable) (SDCCH)

H3029A Failed Internal Intra-Cell Handovers (ChannelUnavailable) (TCH)

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Counter ID Counter Name

H302B Failed Internal Intra-Cell Handovers (TerrestrialResource Request Failed)

H302G Failed Internal Intra-Cell Handovers (A InterfaceFailure)

H3020C Failed Internal Intra-Cell Handovers (Timer Expired)(SDCCH)

H3027Cb Failed Internal Intra-Cell Handovers (Timer Expired)(TCHF) (Signaling Channel)

H3028Cb Failed Internal Intra-Cell Handovers (Timer Expired)(TCHH) (Signaling Channel)

H3027Ca Failed Internal Intra-Cell Handovers (Timer Expired)(TCHF) (Traffic Channel)

H3028Ca Failed Internal Intra-Cell Handovers (Timer Expired)(TCHH) (Traffic Channel)

H302Da Failed Internal Intra-Cell Handovers (Reconnectionto Old Channels) (Abnormal Release, Unspecified)

H302Db Failed Internal Intra-Cell Handovers (Reconnectionto Old Channels) (Abnormal Release, ChannelUnacceptable)

H302Dc Failed Internal Intra-Cell Handovers (Reconnectionto Old Channels) (Abnormal Release, TimerExpired)

H302Dd Failed Internal Intra-Cell Handovers (Reconnectionto Old Channels) (Abnormal Release, No Activity onthe Radio Path)

H302De Failed Internal Intra-Cell Handovers (Reconnectionto Old Channels) (Preemptive Release)

H302Df Failed Internal Intra-Cell Handovers (Reconnectionto Old Channels) (Handover Failed, Timing Advanceout of Range)

H302Dg Failed Internal Intra-Cell Handovers (Reconnectionto Old Channels) (Channel Mode Unavailable)

H302Dh Failed Internal Intra-Cell Handovers (Reconnectionto Old Channels) (Frequency Unavailable)

H302Di Failed Internal Intra-Cell Handovers (Reconnectionto Old Channels) (Call Already Cleared)

H302Dj Failed Internal Intra-Cell Handovers (Reconnectionto Old Channels) (Semantically Incorrect Message)

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Counter ID Counter Name

H302Dk Failed Internal Intra-Cell Handovers (Reconnectionto Old Channels) (Invalid Mandatory Information)

H302Dl Failed Internal Intra-Cell Handovers (Reconnectionto Old Channels) (Message Type Non-existent or NotImplemented)

H302Dm Failed Internal Intra-Cell Handovers (Reconnectionto Old Channels) (Message Type Not Compatiblewith Protocol State)

H302Dn Failed Internal Intra-Cell Handovers (Reconnectionto Old Channels) (Conditional IE Error)

H302Do Failed Internal Intra-Cell Handovers (Reconnectionto Old Channels) (No Cell Allocation Available)

H302Dp Failed Internal Intra-Cell Handovers (Reconnectionto Old Channels) (Protocol Error Unspecified)

H302Dq Failed Internal Intra-Cell Handovers (Reconnectionto Old Channels) (Other Causes)

H3002 Internal Intra-Cell Handover Requests (Underlay toOverlay)

H3001 Internal Intra-Cell Handover Requests (Overlay toUnderlay)

H3012 Internal Intra-Cell Handover Commands (Underlayto Overlay)

H3011 Internal Intra-Cell Handover Commands (Overlay toUnderlay)

H3022A Failed Internal Intra-Cell Handovers (ChannelUnavailable) (Underlay to Overlay)

H3021A Failed Internal Intra-Cell Handovers (ChannelUnavailable) (Overlay to Underlay)

H3022M Failed Internal Intra-Cell Handovers (Other Causes)(Underlay to Overlay)

H3021M Failed Internal Intra-Cell Handovers (Other Causes)(Overlay to Underlay)

H3003A Internal Intra-Cell Handover Requests (DynamicConversion, TCHF-TCHH)

H3003B Internal Intra-Cell Handover Requests (DynamicConversion, TCHH-TCHF)

H3004A Internal Intra-Cell Handover Requests (DynamicConversion, TCH-SDCCH)

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Counter ID Counter Name

H3004B Internal Intra-Cell Handover Requests (DynamicConversion, SDCCH-TCH)

H3013A Internal Intra-Cell Handover Commands (DynamicConversion, TCHF-TCHH)

H3013B Internal Intra-Cell Handover Commands (DynamicConversion, TCHH-TCHF)

H3014A Internal Intra-Cell Handover Commands (DynamicConversion, TCH-SDCCH)

H3014B Internal Intra-Cell Handover Commands (DynamicConversion, SDCCH-TCH)

H3023A Failed Internal Intra-Cell Handovers (DynamicConversion, TCHF-TCHH)

H3023B Failed Internal Intra-Cell Handovers (DynamicConversion, TCHH-TCHF)

H3024A Failed Internal Intra-Cell Handovers (DynamicConversion, TCH-SDCCH)

H3024B Failed Internal Intra-Cell Handovers (DynamicConversion, SDCCH-TCH)

H3055A Internal Intra-Cell Handovers Not Initiated (AMR)(TCHF-TCHH)

H3055B Internal Intra-Cell Handovers Not Initiated (AMR)(TCHH-TCHF)

H3005A Internal Intra-Cell Handover Requests (AMR)(TCHF-TCHH)

H3005B Internal Intra-Cell Handover Requests (AMR)(TCHH-TCHF)

H3015A Internal Intra-Cell Handover Commands (AMR)(TCHF-TCHH)

H3015B Internal Intra-Cell Handover Commands (AMR)(TCHH-TCHF)

H3025A Failed Internal Intra-Cell Handovers (AMR) (TCHF-TCHH)

H3025B Failed Internal Intra-Cell Handovers (AMR)(TCHH-TCHF)

H3040 Internal Intra-Cell Handover Detection MessagesReceived by BSC (SDCCH)

H3047 Internal Intra-Cell Handover Detection MessagesReceived by BSC (TCHF)

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Counter ID Counter Name

H3048 Internal Intra-Cell Handover Detection MessagesReceived by BSC (TCHH)

H3200W Incoming Internal Inter-Cell Handover Requests(SDCCH) (900/850-900/850)

H3200X Incoming Internal Inter-Cell Handover Requests(SDCCH) (1800/1900-1800/1900)

H3200Y Incoming Internal Inter-Cell Handover Requests(SDCCH) (900/850–1800/1900)

H3200Z Incoming Internal Inter-Cell Handover Requests(SDCCH) (1800/1900-900/850)

H3209W Incoming Internal Inter-Cell Handover Requests(TCH) (900/850-900/850)

H3209X Incoming Internal Inter-Cell Handover Requests(TCH) (1800/1900-1800/1900)

H3209Y Incoming Internal Inter-Cell Handover Requests(TCH) (900/850–1800/1900)

H3209Z Incoming Internal Inter-Cell Handover Requests(TCH) (1800/1900-900/850)

H3210W Incoming Internal Inter-Cell Handover Responses(SDCCH) (900/850-900/850)

H3210X Incoming Internal Inter-Cell Handover Responses(SDCCH) (1800/1900-1800/1900)

H3210Y Incoming Internal Inter-Cell Handover Responses(SDCCH) (900/850–1800/1900)

H3210Z Incoming Internal Inter-Cell Handover Responses(SDCCH) (1800/1900-900/850)

H3217W Incoming Internal Inter-Cell Handover Responses(TCHF) (900/850-900/850)

H3217X Incoming Internal Inter-Cell Handover Responses(TCHF) (1800/1900-1800/1900)

H3217Y Incoming Internal Inter-Cell Handover Responses(TCHF) (900/850-1800/1900)

H3217Z Incoming Internal Inter-Cell Handover Responses(TCHF) (1800/1900-900/850)

H3218W Incoming Internal Inter-Cell Handover Responses(TCHH) (900/850–900/850)

H3218X Incoming Internal Inter-Cell Handover Responses(TCHH) (1800/1900-1800/1900)

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Counter ID Counter Name

H3218Y Incoming Internal Inter-Cell Handover Responses(TCHH) (900/850-1800/1900)

H3218Z Incoming Internal Inter-Cell Handover Responses(TCHH) (1800/1900-900/850)

H3220W Failed Incoming Internal Inter-Cell Handovers(SDCCH) (900/850–900/850)

H3220X Failed Incoming Internal Inter-Cell Handovers(SDCCH) (1800/1900-1800/1900)

H3220Y Failed Incoming Internal Inter-Cell Handovers(SDCCH) (900/850-1800/1900)

H3220Z Failed Incoming Internal Inter-Cell Handovers(SDCCH) (1800/1900-900/850)

H3229W Failed Incoming Internal Inter-Cell Handovers(TCH) (900/850-900/850)

H3229X Failed Incoming Internal Inter-Cell Handovers(TCH) (1800/1900-1800/1900)

H3229Y Failed Incoming Internal Inter-Cell Handovers(TCH) (900/850-1800/1900)

H3229Z Failed Incoming Internal Inter-Cell Handovers(TCH) (1800/1900-900/850)

H3220A Failed Incoming Internal Inter-Cell Handovers (NoChannel Available) (SDCCH)

H3229A Failed Incoming Internal Inter-Cell Handovers (NoChannel Available) (TCH)

H322B Failed Incoming Internal Inter-Cell Handovers(Terrestrial Resource Request Failed)

H322D Failed Incoming Internal Inter-Cell Handovers(Reconnection to Old Channels)

H322G Failed Incoming Internal Inter-Cell Handovers (AInterface Failure)

H3220C Failed Incoming Internal Inter-Cell Handovers(Timer Expired) (SDCCH)

H3227Cb Failed Incoming Internal Inter-Cell Handovers(Timer Expired) (TCHF) (Signaling Channel)

H3228Cb Failed Incoming Internal Inter-Cell Handovers(Timer Expired) (TCHH) (Signaling Channel)

H3227Ca Failed Incoming Internal Inter-Cell Handovers(Timer Expired) (TCHF) (Traffic Channel)

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Counter ID Counter Name

H3228Ca Failed Incoming Internal Inter-Cell Handovers(Timer Expired) (TCHH) (Traffic Channel)

H3240 Incoming Internal Inter-Cell Handover DetectionMessages Received by BSC (SDCCH)

H3247 Incoming Internal Inter-Cell Handover DetectionMessages Received by BSC (TCHF)

H3248 Incoming Internal Inter-Cell Handover DetectionMessages Received by BSC (TCHH)

H3100W Outgoing Internal Inter-Cell Handover Requests(SDCCH) (Excluding Directed Retry) (900/850–900/850)

H3100X Outgoing Internal Inter-Cell Handover Requests(SDCCH) (Excluding Directed Retry)(1800/1900-1800/1900)

H3100Y Outgoing Internal Inter-Cell Handover Requests(SDCCH) (Excluding Directed Retry)(900/850-1800/1900)

H3100Z Outgoing Internal Inter-Cell Handover Requests(SDCCH) (Excluding Directed Retry)(1800/1900-900/850)

H3107W Outgoing Internal Inter-Cell Handover Requests(TCHF) (Excluding Directed Retry)(900/850-900/850)

H3107X Outgoing Internal Inter-Cell Handover Requests(TCHF) (Excluding Directed Retry)(1800/1900-1800/1900)

H3107Y Outgoing Internal Inter-Cell Handover Requests(TCHF) (Excluding Directed Retry)(900/850-1800/1900)

H3107Z Outgoing Internal Inter-Cell Handover Requests(TCHF) (Excluding Directed Retry) (1800/1900–900/850)

H3108W Outgoing Internal Inter-Cell Handover Requests(TCHH) (Excluding Directed Retry) (900/850–900/850)

H3108X Outgoing Internal Inter-Cell Handover Requests(TCHH) (Excluding Directed Retry)(1800/1900-1800/1900)

H3108Y Outgoing Internal Inter-Cell Handover Requests(TCHH) (Excluding Directed Retry)(900/850-1800/1900)

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Counter ID Counter Name

H3108Z Outgoing Internal Inter-Cell Handover Requests(TCHH) (Excluding Directed Retry)(1800/1900-900/850)

H3101W Outgoing Internal Inter-Cell Handover Requests(Directed Retry) (900/850-900/850)

H3101X Outgoing Internal Inter-Cell Handover Requests(Directed Retry) (1800/1900-1800/1900)

H3101Y Outgoing Internal Inter-Cell Handover Requests(Directed Retry) (900/850-1800/1900)

H3101Z Outgoing Internal Inter-Cell Handover Requests(Directed Retry) (1800/1900-900/850)

H3110W Outgoing Internal Inter-Cell Handover Commands(SDCCH) (Excluding Directed Retry) (900/850–900/850)

H3110X Outgoing Internal Inter-Cell Handover Commands(SDCCH) (Excluding Directed Retry)(1800/1900-1800/1900)

H3110Y Outgoing Internal Inter-Cell Handover Commands(SDCCH) (Excluding Directed Retry)(900/850-1800/1900)

H3110Z Outgoing Internal Inter-Cell Handover Commands(SDCCH) (Excluding Directed Retry)(1800/1900-900/850)

H3117W Outgoing Internal Inter-Cell Handover Command(TCHF) (Excluding Directed Retry) (900/850–900/850)

H3117X Outgoing Internal Inter-Cell Handover Command(TCHF) (Excluding Directed Retry)(1800/1900-1800/1900)

H3117Y Outgoing Internal Inter-Cell Handover Command(TCHF) (Excluding Directed Retry)(900/850-1800/1900)

H3117Z Outgoing Internal Inter-Cell Handover Command(TCHF) (Excluding Directed Retry)(1800/1900-900/850)

H3118W Outgoing Internal Inter-Cell Handover Command(TCHH) (Excluding Directed Retry) (900/850–900/850)

H3118X Outgoing Internal Inter-Cell Handover Command(TCHH) (Excluding Directed Retry)(1800/1900-1800/1900)

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Counter ID Counter Name

H3118Y Outgoing Internal Inter-Cell Handover Command(TCHH) (Excluding Directed Retry)(900/850-1800/1900)

H3118Z Outgoing Internal Inter-Cell Handover Command(TCHH) (Excluding Directed Retry)(1800/1900-900/850)

H3111W Outgoing Internal Inter-Cell Handover Commands(Directed Retry) (900/850–900/850)

H3111X Outgoing Internal Inter-Cell Handover Commands(Directed Retry) (1800/1900-1800/1900)

H3111Y Outgoing Internal Inter-Cell Handover Commands(Directed Retry) (900/850-1800/1900)

H3111Z Outgoing Internal Inter-Cell Handover Commands(Directed Retry) (1800/1900-900/850)

H3120W Failed Outgoing Internal Inter-Cell Handovers(SDCCH) (Excluding Directed Retry) (900/850–900/850)

H3120X Failed Outgoing Internal Inter-Cell Handovers(SDCCH) (Excluding Directed Retry)(1800/1900-1800/1900)

H3120Y Failed Outgoing Internal Inter-Cell Handovers(SDCCH) (Excluding Directed Retry)(900/850-1800/1900)

H3120Z Failed Outgoing Internal Inter-Cell Handovers(SDCCH) (Excluding Directed Retry)(1800/1900-900/850)

H3127W Failed Outgoing Internal Inter-Cell Handovers(TCHF) (Excluding Directed Retry) (900/850–900/850)

H3127X Failed Outgoing Internal Inter-Cell Handovers(TCHF) (Excluding Directed Retry)(1800/1900-1800/1900)

H3127Y Failed Outgoing Internal Inter-Cell Handovers(TCHF) (Excluding Directed Retry)(900/850-1800/1900)

H3127Z Failed Outgoing Internal Inter-Cell Handovers(TCHF) (Excluding Directed Retry)(1800/1900-900/850)

H3128W Failed Outgoing Internal Inter-Cell Handovers(TCHH) (Excluding Directed Retry) (900/850–900/850)

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Counter ID Counter Name

H3128X Failed Outgoing Internal Inter-Cell Handovers(TCHH) (Excluding Directed Retry)(1800/1900-1800/1900)

H3128Y Failed Outgoing Internal Inter-Cell Handovers(TCHH) (Excluding Directed Retry)(900/850-1800/1900)

H3128Z Failed Outgoing Internal Inter-Cell Handovers(TCHH) (Excluding Directed Retry)(1800/1900-900/850)

H3121W Failed Outgoing Internal Inter-Cell Handovers(Directed Retry) (900/850-900/850)

H3121X Failed Outgoing Internal Inter-Cell Handovers(Directed Retry) (1800/1900-1800/1900)

H3121Y Failed Outgoing Internal Inter-Cell Handovers(Directed Retry) (900/850-1800/1900)

H3121Z Failed Outgoing Internal Inter-Cell Handovers(Directed Retry) (1800/1900-900/850)

H312A Failed Outgoing Internal Inter-Cell Handovers (NoChannel Available)

H312B Failed Outgoing Internal Inter-Cell Handovers(Terrestrial Resource Request Failed)

H312G Failed Outgoing Internal Inter-Cell Handovers (AInterface Failure)

H3120C Failed Outgoing Internal Inter-Cell Handovers(Timer Expired) (SDCCH) (Excluding DirectedRetry)

H3127Cb Failed Outgoing Internal Inter-Cell Handovers(Timer Expired) (TCHF) (Signaling Channel)

H3128Cb Failed Outgoing Internal Inter-Cell Handovers(Timer Expired) (TCHH) (Signaling Channel)

H3127Ca Failed Outgoing Internal Inter-Cell Handovers(Timer Expired) (TCHF) (Traffic Channel)

H3128Ca Failed Outgoing Internal Inter-Cell Handovers(Timer Expired) (TCHH) (Traffic Channel)

H3121C Failed Outgoing Internal Inter-Cell Handovers(Timer Expired) (Directed Retry)

H312Da Failed Outgoing Internal Inter-Cell Handovers(Reconnection to Old Channels) (Abnormal Release,Unspecified)

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Counter ID Counter Name

H312Db Failed Outgoing Internal Inter-Cell Handovers(Reconnection to Old Channels) (Abnormal Release,Channel Unacceptable)

H312Dc Failed Outgoing Internal Inter-Cell Handovers(Reconnection to Old Channels) (Abnormal Release,Timer Expired)

H312Dd Failed Outgoing Internal Inter-Cell Handovers(Reconnection to Old Channels) (Abnormal Release,No Activity on the Radio Path)

H312De Failed Outgoing Internal Inter-Cell Handovers(Reconnection to Old Channels) (PreemptiveRelease)

H312Df Failed Outgoing Internal Inter-Cell Handovers(Reconnection to Old Channels) (Handover Failed,Timing Advance out of Range)

H312Dg Failed Outgoing Internal Inter-Cell Handovers(Reconnection to Old Channels) (Channel ModeUnavailable)

H312Dh Failed Outgoing Internal Inter-Cell Handovers(Reconnection to Old Channels) (FrequencyUnavailable)

H312Di Failed Outgoing Internal Inter-Cell Handovers(Reconnection to Old Channels) (Call AlreadyCleared)

H312Dj Failed Outgoing Internal Inter-Cell Handovers(Reconnection to Old Channels) (SemanticallyIncorrect Message)

H312Dk Failed Outgoing Internal Inter-Cell Handovers(Reconnection to Old Channels) (Invalid MandatoryInformation)

H312Dl Failed Outgoing Internal Inter-Cell Handovers(Reconnection to Old Channels) (Message TypeNon-existent or Not Implemented)

H312Dm Failed Outgoing Internal Inter-Cell Handovers(Reconnection to Old Channels) (Message Type NotCompatible with Protocol State)

H312Dn Failed Outgoing Internal Inter-Cell Handovers(Reconnection to Old Channels) (Conditional IEError)

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Counter ID Counter Name

H312Do Failed Outgoing Internal Inter-Cell Handovers(Reconnection to Old Channels) (No Cell AllocationAvailable)

H312Dp Failed Outgoing Internal Inter-Cell Handovers(Reconnection to Old Channels) (Protocol ErrorUnspecified)

H312Dq Failed Outgoing Internal Inter-Cell Handovers(Reconnection to Old Channels) (Other Causes)

H310A Outgoing Internal Inter-Cell Handover Requests(Uplink Quality)

H310B Outgoing Internal Inter-Cell Handover Requests(Downlink Quality)

H310C Outgoing Internal Inter-Cell Handover Requests(Uplink Strength)

H310D Outgoing Internal Inter-Cell Handover Requests(Downlink Strength)

H310E Outgoing External Inter-Cell Handover Requests(Timing Advance)

H310F Outgoing Internal Inter-Cell Handover Requests(Better Cell)

H310G Outgoing Internal Inter-Cell Handover Requests(Load)

H310H Number of Outgoing Internal Inter-Cell HandoverRequests (Rapid Level Drop)

H310I Number of Outgoing Internal Inter-Cell HandoverRequests (MSC Intervention)

H310J Outgoing Internal Inter-Cell Handover Requests(OM Intervention)

H310L Outgoing Internal Inter-Cell Handover Requests(Other Causes)

H311A Outgoing Internal Inter-Cell Handover Commands(Uplink Quality)

H311B Outgoing Internal Inter-Cell Handover Commands(Downlink Quality)

H311C Outgoing Internal Inter-Cell Handover Commands(Uplink Strength)

H311D Outgoing Internal Inter-Cell Handover Commands(Downlink Strength)

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Counter ID Counter Name

H311E Outgoing External Inter-Cell Handover Commands(Timing Advance)

H311F Outgoing Internal Inter-Cell Handover Commands(Better Cell)

H311G Outgoing Internal Inter-Cell Handover Commands(Load)

H311H Outgoing Internal Inter-Cell Handover Commands(Rapid Level Drop)

H311I Outgoing Internal Inter-Cell Handover Commands(MSC Intervention)

H311J Outgoing Internal Inter-Cell Handover Commands(OM Intervention)

H311L Outgoing Internal Inter-Cell Handover Commands(Other Causes)

H3122A Failed Outgoing Internal Inter-Cell Handovers(Uplink Quality)

H3122B Failed Outgoing Internal Inter-Cell Handovers(Downlink Quality)

H3122C Failed Outgoing Internal Inter-Cell Handovers(Uplink Strength)

H3122D Failed Outgoing Internal Inter-Cell Handovers(Downlink Strength)

H3122E Failed Outgoing Internal Inter-Cell Handovers(Timing Advance)

H3122F Failed Outgoing Internal Inter-Cell Handovers(Better Cell)

H3122G Failed Outgoing Internal Inter-Cell Handovers(Load)

H3122H Failed Outgoing Internal Inter-Cell Handovers(Rapid Level Drop)

H3122I Failed Outgoing Internal Inter-Cell Handovers (MSCIntervention)

H3122J Failed Outgoing Internal Inter-Cell Handovers (OMIntervention)

H3122L Failed Outgoing Internal Inter-Cell Handovers(Other Causes)

H3400W Incoming External Inter-Cell Handover Requests(SDCCH) (900/850–900/850)

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BSS Feature Parameter Description

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Counter ID Counter Name

H3400X Incoming External Inter-Cell Handover Requests(SDCCH) (1800/1900-1800/1900)

H3400Y Incoming External Inter-Cell Handover Requests(SDCCH) (900/850-1800/1900)

H3400Z Incoming External Inter-Cell Handover Requests(SDCCH) (1800/1900-900/850)

H3409W Incoming External Inter-Cell Handover Requests(TCH) (900/850-900/850)

H3409X Incoming External Inter-Cell Handover Requests(TCH) (1800/1900-1800/1900)

H3409Y Incoming External Inter-Cell Handover Requests(TCH) (900/850-1800/1900)

H3409Z Incoming External Inter-Cell Handover Requests(TCH) (1800/1900-900/850)

H3410W Incoming External Inter-Cell Handover Responses(SDCCH) (900/850-900/850)

H3410X Incoming External Inter-Cell Handover Responses(SDCCH) (1800/1900-1800/1900)

H3410Y Incoming External Inter-Cell Handover Responses(SDCCH) (900/850-1800/1900)

H3410Z Incoming External Inter-Cell Handover Responses(SDCCH) (1800/1900-900/850)

H3417W Incoming External Inter-Cell Handover Responses(TCHF) (900/850-900/850)

H3417X Incoming External Inter-Cell Handover Responses(TCHF) (1800/1900-1800/1900)

H3417Y Incoming External Inter-Cell Handover Responses(TCHF) (900/850-1800/1900)

H3417Z Incoming External Inter-Cell Handover Responses(TCHF) (1800/1900-900/850)

H3418W Incoming External Inter-Cell Handover Responses(TCHH) (900/850-900/850)

H3418X Incoming External Inter-Cell Handover Responses(TCHH) (1800/1900-1800/1900)

H3418Y Incoming External Inter-Cell Handover Responses(TCHH) (900/850-1800/1900)

H3418Z Incoming External Inter-Cell Handover Responses(TCHH) (1800/1900-900/850)

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Counter ID Counter Name

H3420W Failed Incoming External Inter-Cell Handovers(SDCCH) (900/850-900/850)

H3420X Failed Incoming External Inter-Cell Handovers(SDCCH) (1800/1900-1800/1900)

H3420Y Failed Incoming External Inter-Cell Handovers(SDCCH) (900/850-1800/1900)

H3420Z Failed Incoming External Inter-Cell Handovers(SDCCH) (1800/1900-900/850)

H3429W Failed Incoming External Inter-Cell Handovers(TCH) (900/850-900/850)

H3429X Failed Incoming External Inter-Cell Handovers(TCH) (1800/1900-1800/1900)

H3429Y Failed Incoming External Inter-Cell Handovers(TCH) (900/850-1800/1900)

H3429Z Failed Incoming External Inter-Cell Handovers(TCH) (1800/1900-900/850)

H3401B Incoming External Inter-Cell Handover TCHRequests (TCHF Only)

H3401C Incoming External Inter-Cell Handover TCHRequests (TCHH Only)

H3401D Incoming External Inter-Cell Handover TCHRequests (TCHF Preferred, Channel TypeUnchangeable)

H3401E Incoming External Inter-Cell Handover TCHRequests (TCHH Preferred, Channel TypeUnchangeable)

H3401G Incoming External Inter-Cell Handover TCHRequests (TCHF Preferred, Channel TypeChangeable)

H3401H Incoming External Inter-Cell Handover TCHRequests (TCHH Preferred, Channel TypeChangeable)

H3401F Incoming External Inter-Cell Handover TCHRequests (TCHF or TCHH, Channel TypeUnchangeable)

H3401I Incoming External Inter-Cell Handover TCHRequests (TCHF or TCHH, Channel TypeChangeable)

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BSS Feature Parameter Description

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Counter ID Counter Name

H342I Failed Incoming External Inter-Cell Handovers(Invalid Message)

H3420A Failed Incoming External Inter-Cell Handovers (NoChannel Available) (SDCCH)

H3429A Failed Incoming External Inter-Cell Handovers (NoChannel Available) (TCH)

H342E Failed Incoming External Inter-Cell Handovers (CICUnavailable)

H342F Failed Incoming External Inter-Cell Handovers (CICAllocated)

H342B Failed Incoming External Inter-Cell Handovers(Terrestrial Resource Request Failed)

H342H Failed Incoming External Inter-Cell Handovers(Clear Commands Sent By MSC)

H3420C Failed Incoming External Inter-Cell Handovers(Timer Expired) (SDCCH)

H3429Cb Failed Incoming External Inter-Cell Handovers(Timer Expired) (TCH) (Signaling Channel)

H3429Ca Failed Incoming External Inter-Cell Handovers(Timer Expired) (TCH) (Traffic Channel)

H3440 Incoming External Inter-Cell Handover DetectionMessages Received by BSC (SDCCH)

H3447 Incoming External Inter-Cell Handover DetectionMessages Received by BSC (TCHF)

H3448 Incoming External Inter-Cell Handover DetectionMessages Received by BSC (TCHH)

H3300W Outgoing External Inter-Cell Handover Requests(SDCCH) (Excluding Directed Retry) (900/850–900/850)

H3300X Outgoing External Inter-Cell Handover Requests(SDCCH) (Excluding Directed Retry)(1800/1900-1800/1900)

H3300Y Outgoing External Inter-Cell Handover Requests(SDCCH) (Excluding Directed Retry)(900/850-1800/1900)

H3300Z Outgoing External Inter-Cell Handover Requests(SDCCH) (Excluding Directed Retry)(1800/1900-900/850)

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Counter ID Counter Name

H3310W Outgoing External Inter-Cell Handover Commands(SDCCH) (Excluding Directed Retry) (900/850–900/850)

H3310X Outgoing External Inter-Cell Handover Commands(SDCCH) (Excluding Directed Retry)(1800/1900-1800/1900)

H3310Y Outgoing External Inter-Cell Handover Commands(SDCCH) (Excluding Directed Retry)(900/850-1800/1900)

H3310Z Outgoing External Inter-Cell Handover Commands(SDCCH) (Excluding Directed Retry)(1800/1900-900/850)

H3317W Outgoing External Inter-Cell Handover Commands(TCHF) (Excluding Directed Retry) (900/850–900/850)

H3317X Outgoing External Inter-Cell Handover Commands(TCHF) (Excluding Directed Retry)(1800/1900-1800/1900)

H3317Y Outgoing External Inter-Cell Handover Commands(TCHF) (Excluding Directed Retry)(900/850-1800/1900)

H3317Z Outgoing External Inter-Cell Handover Commands(TCHF) (Excluding Directed Retry)(1800/1900-900/850)

H3318W Outgoing External Inter-Cell Handover Commands(TCHH) (Excluding Directed Retry) (900/850–900/850)

H3318X Outgoing External Inter-Cell Handover Commands(TCHH) (Excluding Directed Retry)(1800/1900-1800/1900)

H3318Y Outgoing External Inter-Cell Handover Commands(TCHH) (Excluding Directed Retry)(900/850-1800/1900)

H3318Z Outgoing External Inter-Cell Handover Commands(TCHH) (Excluding Directed Retry)(1800/1900-900/850)

H3311W Outgoing External Inter-Cell Handover Commands(Directed Retry) (900/850–900/850)

H3311X Outgoing External Inter-Cell Handover Commands(Directed Retry) (1800/1900-1800/1900)

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BSS Feature Parameter Description

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Counter ID Counter Name

H3311Y Outgoing External Inter-Cell Handover Commands(Directed Retry) (900/850-1800/1900)

H3311Z Outgoing External Inter-Cell Handover Commands(Directed Retry) (1800/1900–900/850)

H3320W Failed Outgoing External Inter-Cell Handovers(SDCCH) (Excluding Directed Retry) (900/850–900/850)

H3320X Failed Outgoing External Inter-Cell Handovers(SDCCH) (Excluding Directed Retry)(1800/1900-1800/1900)

H3320Y Failed Outgoing External Inter-Cell Handovers(SDCCH) (Excluding Directed Retry)(900/850-1800/1900)

H3320Z Failed Outgoing External Inter-Cell Handovers(SDCCH) (Excluding Directed Retry)(1800/1900-900/850)

H3327W Failed Outgoing External Inter-Cell Handovers(TCHF) (Excluding Directed Retry) (900/850–900/850)

H3327X Failed Outgoing External Inter-Cell Handovers(TCHF) (Excluding Directed Retry)(1800/1900-1800/1900)

H3327Y Failed Outgoing External Inter-Cell Handovers(TCHF) (Excluding Directed Retry)(900/850-1800/1900)

H3327Z Failed Outgoing External Inter-Cell Handovers(TCHF) (Excluding Directed Retry)(1800/1900-900/850)

H3328W Failed Outgoing External Inter-Cell Handovers(TCHH) (Excluding Directed Retry) (900/850–900/850)

H3328X Failed Outgoing External Inter-Cell Handovers(TCHH) (Excluding Directed Retry)(1800/1900-1800/1900)

H3328Y Failed Outgoing External Inter-Cell Handovers(TCHH) (Excluding Directed Retry)(900/850-1800/1900)

H3328Z Failed Outgoing External Inter-Cell Handovers(TCHH) (Excluding Directed Retry)(1800/1900-900/850)

HUAWEI GSM Base Station SubsystemBSS Feature Parameter Description 1 Handover

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Counter ID Counter Name

H3321W Failed Outgoing External Inter-Cell Handovers(Directed Retry) (900/850-900/850)

H3321X Failed Outgoing External Inter-Cell Handovers(Directed Retry) (1800/1900-1800/1900)

H3321Y Failed Outgoing External Inter-Cell Handovers(Directed Retry) (900/850-1800/1900)

H3321Z Failed Outgoing External Inter-Cell Handovers(Directed Retry) (1800/1900-900/850)

H330A Outgoing Internal Inter-Cell Handover Requests(Uplink Quality)

H330B Outgoing External Inter-Cell Handover Requests(Downlink Quality)

H330C Outgoing External Inter-Cell Handover Requests(Uplink Strength)

H330D Outgoing External Inter-Cell Handover Requests(Downlink Strength)

H330E Outgoing External Inter-Cell Handover Requests(Timing Advance)

H330F Outgoing External Inter-Cell Handover Requests(Better Cell)

H330G Outgoing External Inter-Cell Handover Requests(Load)

H330H Outgoing External Inter-Cell Handover Requests(Rapid Level Drop)

H330I Outgoing External Inter-Cell Handover Requests(MSC Intervention)

H330J Outgoing External Inter-Cell Handover Requests(OM Intervention)

H330L Outgoing External Inter-Cell Handover Requests(Other Causes)

H331A Outgoing External Inter-Cell Handover Commands(Uplink Quality)

H331B Outgoing External Inter-Cell Handover Commands(Downlink Quality)

H331C Outgoing External Inter-Cell Handover Commands(Uplink Strength)

H331D Outgoing External Inter-Cell Handover Commands(Downlink Strength)

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BSS Feature Parameter Description

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Counter ID Counter Name

H331E Outgoing External Inter-Cell Handover Commands(Timing Advance)

H331F Outgoing External Inter-Cell Handover Commands(Better Cell)

H331G Outgoing External Inter-Cell Handover Commands(Load)

H331H Outgoing External Inter-Cell Handover Commands(Rapid Level Drop)

H331I Outgoing External Inter-Cell Handover Commands(MSC Intervention)

H331J Outgoing External Inter-Cell Handover Commands(OM Intervention)

H331L Outgoing External Inter-Cell Handover Commands(Other Causes)

H3322A Failed Outgoing External Inter-Cell Handovers(Uplink Quality)

H3322B Failed Outgoing External Inter-Cell Handovers(Downlink Quality)

H3322C Failed Outgoing External Inter-Cell Handovers(Uplink Strength)

H3322D Failed Outgoing External Inter-Cell Handovers(Downlink Strength)

H3322E Failed Outgoing External Inter-Cell Handovers(Timing Advance)

H3322F Failed Outgoing External Inter-Cell Handovers(Better Cell)

H3322G Failed Outgoing External Inter-Cell Handovers(Load)

H3322H Failed Outgoing External Inter-Cell Handovers(Rapid Level Drop)

H3322I Failed Outgoing External Inter-Cell Handovers(MSC Intervention)

H3322J Failed Outgoing External Inter-Cell Handovers (OMIntervention)

H3322L Failed Outgoing External Inter-Cell Handovers(Other Causes)

H332Ka Failed Outgoing External Inter-Cell Handovers(Handover Request Rejected) (OM Intervention)

HUAWEI GSM Base Station SubsystemBSS Feature Parameter Description 1 Handover

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Counter ID Counter Name

H332Kb Failed Outgoing External Inter-Cell Handovers(Handover Request Rejected) (Equipment Failure)

H332Kc Failed Outgoing External Inter-Cell Handovers(Handover Request Rejected) (No Radio ResourceAvailable)

H332Kd Failed Outgoing External Inter-Cell Handovers(Handover Request Rejected) (Requested TerrestrialResource Unavailable)

H332Ke Failed Outgoing External Inter-Cell Handovers(Handover Request Rejected) (BSS not Equipped)

H332Kf Failed Outgoing External Inter-Cell Handovers(Handover Request Rejected) (Invalid Cell)

H332Kg Failed Outgoing External Inter-Cell Handovers(Handover Request Rejected) (RequestedTranscoding/Rate Adaption Unavailable)

H332Kh Failed Outgoing External Inter-Cell Handovers(Handover Request Rejected) (Circuit PoolMismatch)

H332Ki Failed Outgoing External Inter-Cell Handovers(Handover Request Rejected) (Requested SpeechVersion Unavailable)

H332Kj Failed Outgoing External Inter-Cell Handovers(Handover Request Rejected) (Ciphering Algorithmnot Supported)

H332Kk Failed Outgoing External Inter-Cell Handovers(Handover Request Rejected) (Terrestrial circuitalready allocated)

H332Kl Failed Outgoing External Inter-Cell Handovers(Handover Request Rejected) (Invalid Message)

H332Km Failed Outgoing External Inter-Cell Handovers(Handover Request Rejected) (Protocol Errorbetween BSS and MSC)

H332Kn Failed Outgoing External Inter-Cell Handovers(Handover Request Rejected) (Other Causes)

H332Da Failed Outgoing External Inter-Cell Handovers(Reconnection to Old Channels) (Abnormal Release,Unspecified)

H332Db Failed Outgoing External Inter-Cell Handovers(Reconnection to Old Channels) (Abnormal Release,Channel Unacceptable)

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BSS Feature Parameter Description

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Counter ID Counter Name

H332Dc Failed Outgoing External Inter-Cell Handovers(Reconnection to Old Channels) (Abnormal Release,Timer Expired)

H332Dd Failed Outgoing External Inter-Cell Handovers(Reconnection to Old Channels) (Abnormal Release,No Activity on the Radio Path)

H332De Failed Outgoing External Inter-Cell Handovers(Reconnection to Old Channels) (PreemptiveRelease)

H332Df Failed Outgoing External Inter-Cell Handovers(Reconnection to Old Channels) (Handover Failed,Timing Advance out of Range)

H332Dg Failed Outgoing External Inter-Cell Handovers(Reconnection to Old Channels) (Channel ModeUnavailable)

H332Dh Failed Outgoing External Inter-Cell Handovers(Reconnection to Old Channels) (FrequencyUnavailable)

H332Di Failed Outgoing External Inter-Cell Handovers(Reconnection to Old Channels) (Call AlreadyCleared)

H332Dj Failed Outgoing External Inter-Cell Handovers(Reconnection to Old Channels) (SemanticallyIncorrect Message)

H332Dk Failed Outgoing External Inter-Cell Handovers(Reconnection to Old Channels) (Invalid MandatoryInformation)

H332Dl Failed Outgoing External Inter-Cell Handovers(Reconnection to Old Channels) (Message TypeNon-existent or Not Implemented)

H332Dm Failed Outgoing External Inter-Cell Handovers(Reconnection to Old Channels) (Message Type NotCompatible with Protocol State)

H332Dn Failed Outgoing External Inter-Cell Handovers(Reconnection to Old Channels) (Conditional IEError)

H332Do Failed Outgoing External Inter-Cell Handovers(Reconnection to Old Channels) (No Cell AllocationAvailable)

HUAWEI GSM Base Station SubsystemBSS Feature Parameter Description 1 Handover

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Counter ID Counter Name

H332Dp Failed Outgoing External Inter-Cell Handovers(Reconnection to Old Channels) (Protocol ErrorUnspecified)

H332Dq Failed Outgoing External Inter-Cell Handovers(Reconnection to Old Channels) (Other Causes)

H332Ha Failed Outgoing External Inter-Cell Handovers(Clear Commands Sent By MSC) (Radio InterfaceMessage Failure)

H332Hb Failed Outgoing External Inter-Cell Handovers(Clear Commands Sent By MSC) (Radio InterfaceFailure)

H332Hc Failed Outgoing External Inter-Cell Handovers(Clear Commands Sent By MSC) (OM Intervention)

H332Hd Failed Outgoing External Inter-Cell Handovers(Clear Commands Sent By MSC) (EquipmentFailure)

H332He Failed Outgoing External Inter-Cell Handovers(Clear Commands Sent By MSC) (Preemption)

H332Hf Failed Outgoing External Inter-Cell Handovers(Clear Commands Sent By MSC) (Invalid Message)

H332Hg Failed Outgoing External Inter-Cell Handovers(Clear Commands Sent By MSC) (Protocol Errorbetween BSS and MSC)

H332Hh Failed Outgoing External Inter-Cell Handovers(Clear Commands Sent By MSC) (Other Causes)

H332G Failed Outgoing External Inter-Cell Handovers (AInterface Failure)

H3320L Failed Outgoing External Inter-Cell Handovers (T7Expiry) (SDCCH) (Excluding Directed Retry)

H3327Lb Failed Outgoing External Inter-Cell Handovers (T7Expiry) (TCHF) (Signaling Channel)

H3328Lb Failed Outgoing External Inter-Cell Handovers (T7Expiry) (TCHH) (Signaling Channel)

H3327La Failed Outgoing External Inter-Cell Handovers (T7Expired) (TCHF) (Traffic Channel)

H3328La Failed Outgoing External Inter-Cell Handovers (T7Expired) (TCHH) (Traffic Channel)

H3321L Failed Outgoing External Inter-Cell Handovers (T7Expired) (Directed Retry)

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BSS Feature Parameter Description

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Counter ID Counter Name

H3320C Failed Outgoing External Inter-Cell Handovers (T8Expiry) (SDCCH) (Excluding Directed Retry)

H3327Cb Failed Outgoing External Inter-Cell Handovers (T8Expiry) (TCHF) (Signaling Channel)

H3328Cb Failed Outgoing External Inter-Cell Handovers (T8Expiry) (TCHH) (Signaling Channel)

H3327Ca Failed Outgoing External Inter-Cell Handovers (T8Expired) (TCHF) (Traffic Channel)

H3328Ca Failed Outgoing External Inter-Cell Handovers (T8Expired) (TCHH) (Traffic Channel)

H3321C Failed Outgoing External Inter-Cell Handovers (T8Expired) (Directed Retry)

H3303 Outgoing External Inter-Cell Handover Requests(Different Signaling Points)

H3313 Outgoing External Inter-Cell Handover Commands(Different Signaling Points)

H3323 Failed Outgoing External Inter-Cell Handovers(Different Signaling Points)

H3307W Outgoing External Inter-Cell Handover Requests(TCHF) (Excluding Directed Retry) (900/850–900/850)

H3307X Outgoing External Inter-Cell Handover Requests(TCHF) (Excluding Directed Retry)(1800/1900-1800/1900)

H3307Y Outgoing External Inter-Cell Handover Requests(TCHF) (Excluding Directed Retry)(900/850-1800/1900)

H3307Z Outgoing External Inter-Cell Handover Requests(TCHF) (Excluding Directed Retry)(1800/1900-900/850)

H3308W Outgoing External Inter-Cell Handover Requests(TCHH) (Excluding Directed Retry) (900/850–900/850)

H3308X Outgoing External Inter-Cell Handover Requests(TCHH) (Excluding Directed Retry)(1800/1900-1800/1900)

H3308Y Outgoing External Inter-Cell Handover Requests(TCHH) (Excluding Directed Retry)(900/850-1800/1900)

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Counter ID Counter Name

H3308Z Outgoing External Inter-Cell Handover Requests(TCHH) (Excluding Directed Retry)(1800/1900-900/850)

H3301W Outgoing External Inter-Cell Handover Requests(Directed Retry) (900/850-900/850)

H3301X Outgoing External Inter-Cell Handover Requests(Directed Retry) (1800/1900-1800/1900)

H3301Y Outgoing External Inter-Cell Handover Requests(Directed Retry) (900/850-1800/1900)

H3301Z Outgoing External Inter-Cell Handover Requests(Directed Retry) (1800/1900-900/850)

H380 Cell Incoming Handover Requests

H382A Failed Cell Incoming Handovers (Congestion)

H382M Failed Cell Incoming Handovers (Other Causes)

H371A Cell Outgoing Handover Commands (UplinkQuality)

H371B Cell Outgoing Handover Commands (DownlinkQuality)

H371C Cell Outgoing Handover Commands (UplinkStrength)

H371D Cell Outgoing Handover Commands (DownlinkStrength)

H371E Cell Outgoing Handover Commands (TimingAdvance)

H371F Cell Outgoing Handover Commands (Better Cell)

H371G Cell Outgoing Handover Commands (Load)

H371H Cell Outgoing Handover Commands (Rapid LevelDrop)

H371I Cell Outgoing Handover Commands (MSCIntervention)

H371J Cell Outgoing Handover Commands (OMIntervention)

H371L Cell Outgoing Handover Commands (Other Causes)

H372A Failed Cell Outgoing Handovers (Uplink Quality)

H372B Failed Cell Outgoing Handovers (Downlink Quality)

H372C Failed Cell Outgoing Handovers (Uplink Strength)

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BSS Feature Parameter Description

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Counter ID Counter Name

H372D Failed Cell Outgoing Handovers (DownlinkStrength)

H372E Failed Cell Outgoing Handovers (Timing Advance)

H372F Failed Cell Outgoing Handovers (Better Cell)

H372G Failed Cell Outgoing Handovers (Load)

H372H Failed Cell Outgoing Handovers (Rapid Level Drop)

H372I Failed Cell Outgoing Handovers (MSC Intervention)

H372J Failed Cell Outgoing Handovers (OM Intervention)

H372L Failed Cell Outgoing Handovers (Other Causes)

S3300C Number of MRs during Handover Initiation (UplinkReceive Level Rank = 0)

S3301C Number of MRs during Handover Initiation (UplinkReceive Level Rank = 1)

S3302C Number of MRs during Handover Initiation (UplinkReceive Level Rank = 2)

S3303C Number of MRs during Handover Initiation (UplinkReceive Level Rank = 3)

S3304C Number of MRs during Handover Initiation (UplinkReceive Level Rank = 4)

S3305C Number of MRs during Handover Initiation (UplinkReceive Level Rank = 5)

S3306C Number of MRs during Handover Initiation (UplinkReceive Level Rank = 6)

S3307C Number of MRs during Handover Initiation (UplinkReceive Level Rank = 7)

S3310C Number of MRs during Handover Initiation (UplinkReceive Quality Rank = 0)

S3311C Number of MRs during Handover Initiation (UplinkReceive Quality Rank = 1)

S3312C Number of MRs during Handover Initiation (UplinkReceive Quality Rank = 2)

S3313C Number of MRs during Handover Initiation (UplinkReceive Quality Rank = 3)

S3314C Number of MRs during Handover Initiation (UplinkReceive Quality Rank = 4)

HUAWEI GSM Base Station SubsystemBSS Feature Parameter Description 1 Handover

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Counter ID Counter Name

S3315C Number of MRs during Handover Initiation (UplinkReceive Quality Rank = 5)

S3316C Number of MRs during Handover Initiation (UplinkReceive Quality Rank = 6)

S3317C Number of MRs during Handover Initiation (UplinkReceive Quality Rank = 7)

AS330C Mean Uplink Receiving Level during HandoverInitiation

AS331C Mean Uplink Receive Quality during HandoverInitiation

AS330A Mean Uplink Receive Level during Concentric CellHandover Initiation (Overlay to Underlay)

AS332A Mean Downlink Receive Level during ConcentricCell Handover Initiation (Overlay to Underlay)

AS330B Mean Uplink Receive Level during Concentric CellHandover Initiation (Underlay to Overlay)

AS332B Mean Downlink Receive Level during ConcentricCell Handover Initiation (Underlay to Overlay)

AS334A Mean Timing Advance during Concentric CellHandover Initiation (Overlay to Underlay)

AS334B Mean Timing Advance during Concentric CellHandover Initiation (Underlay to Overlay)

1.5 Reference Documents

l GSM 08.58

l GSM 04.08

1 HandoverHUAWEI GSM Base Station Subsystem

BSS Feature Parameter Description

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Index

HUAWEI GSM Base Station SubsystemBSS Feature Parameter Description Index

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i-1