55958275 01-11-amr

11 AMR

About This Chapter

AvailabilityNone

ImpactNone

Technical DescriptionThe information related to the radio link timer in AMR is added.

NOTE

The AMR radio link timer has been developed in R3 version but not included in Feature Description ofthe R3 version. The related information is added to Feature Description in the R8 version.

ImplementationYou need to configure the AMR radio link timer during the configuration process.

Maintenance InformationCounter

Table 11-1 AMR service measurement per cell

Counter Meaning

A0401A The Requst Times Of Full Rate Speech Version 1

A0401B The Requst Times Of Full Rate Speech Version 2

A0401C The Requst Times Of Full Rate Speech Version 3

HUAWEI BSC6000 Base Station SubsystemBSS Feature Description 11 AMR

Issue 03 (2008-01-25) Huawei Proprietary and ConfidentialCopyright © Huawei Technologies Co., Ltd

11-1

Counter Meaning

A0402A The Requst Times Of Half Rate Speech Version 1

A0402B The Requst Times Of Half Rate Speech Version 2

A0402C The Requst Times Of Half Rate Speech Version 3

A0409A The Number Of Speech Version Message

A0409B The Call Proportion Of Full Rate Speech Version 1

A0409C The Call Proportion Of Full Rate Speech Version 2

A0409D The Call Proportion Of Full Rate Speech Version 3

A0409E The Call Proportion Of Half Rate Speech Version 1

A0409F The Call Proportion Of Half Rate Speech Version 2

A0409G The Call Proportion Of Half Rate Speech Version 3

M0121A Full Rate AMR Service Channel Call Drop Times

M0121B Half Rate AMR Service Channel Call Drop Times

A0409H Full Rate TCH Successful Occupancy Times (Signaling Channel)

A0409I Full Rate AMR TCH Successful Call Occupancy Times (Service Channel)

A0409J Full Rate AMR TCH Successful Handover Occupancy Times (ServiceChannel)

A0409K Half Rate TCH Successful Occupancy Times (Signaling Channel)

A0409L Half Rate AMR TCH Successful Call Occupancy Times (Service Channel)

A0409M Half Rate AMR TCH Successful Handover Occupancy Times (ServiceChannel)

A0409N Full Rate AMR Call Drop Ratio

A0409P Half Rate AMR Call Drop Ratio

Table 11-2 AMR channel status measurement per cell

Counter Meaning

R3551C AMR Service Channel Busy Number (TCHF)

R3552C AMR Service Channel Busy Number (TCHH)

AR3551C Traffic Volume of AMR TCHFs

AR3552C Traffic Volume of AMR TCHHs

11 AMRHUAWEI BSC6000 Base Station Subsystem

BSS Feature Description

11-2 Huawei Proprietary and ConfidentialCopyright © Huawei Technologies Co., Ltd

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Table 11-3 AMR power control message measurement per cell

Counter Meaning

S3240A AMR MS Power Level

S3241A AMR BTS Power Level

S3291A Total Number of Measurement Reports for AMR with MS Power Level

S3290A Total Number of Measurement Reports for AMR with BTS Power Level

AS3240A AMR MS Average Power Level

AS3241A AMR BTS Average Power Level

Table 11-4 RQI measurement per TRX

Counter Meaning

S4400E Number of Measurement Reports (RQI = 0 to 1)





















11-3

Counter Meaning

S4419E Number of Measurement Reports (RQI greater than 55)

S4420E Ratio (RQI = 0 to 1)



















S4439E Ratio (RQI greater than 55)

11.1 OverviewThis describes the characteristics of AMR. The automatic selection of an appropriate coding/decoding rate in the AMR can help improve the anti-interference performance and speech qualityof a wireless communication system.

11.2 AvailabilityThis lists the NEs and software required for the implementation of AMR. Some specialrequirements are also listed here.

11.3 Technical DescriptionThis describes the characteristics of the AMR, which allows the BTS and the MS to adjust thecodec rate based on the measured parameters, such as receive level, receive quality, and C/Iratio. An appropriate codec rate can be obtained with the configuration of the AMR call controlparameters in the BSC and the adjustment of the parameters in the MS through the Um interface.




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In this way, the anti-interference capability and the voice quality in the wireless communicationsystem can be improved.

11.4 CapabilitiesThis describes the functions supported by AMR and the limitations on AMR.

11.5 ImplementationThis describes how to configure, verify, and disable AMR.

11.6 Maintenance InformationThis lists the counters related to AMR.

11.7 References



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11.1 OverviewThis describes the characteristics of AMR. The automatic selection of an appropriate coding/decoding rate in the AMR can help improve the anti-interference performance and speech qualityof a wireless communication system.

Definition

AMR is an adaptive multi-rate speech coding/decoding algorithm, which is termed full-ratespeech version 3 and half-rate speech version 3 in GSM specifications. This algorithm enablesa BTS and an MS to select an appropriate coding/decoding rate automatically as the interferencein the radio network changes so that the anti-interference performance and the speech quality ofthe wireless communication system can be improved.

AMR is applicable to the speech service in the wireless communication system and is notapplicable to the CS data service or PS service.

Purposes

In the wireless communication system, the higher the speech codec rate, the more speech featureinformation is carried in the coded stream, and thus the higher fidelity the speech is. However,with the increase of the codec rate, the redundant information in the coded stream decreases,and thus the coded stream becomes more interference sensitive. In a poor wirelesscommunication environment, bit errors occur easily and the speech frames may get lost. Thus,voices may be intermittent. With the increase of the codec rate, more redundant information iscarried in the coded stream. Thus, the coded stream is less sensitive to interface and the continuityof voice can be improved.

With AMR, the BTS and the MS can evaluate the interference in the radio network based on thedetected parameters such as receive level, receive quality, and carrier-to-interference ratio, andthen adjust the codec rate accordingly.

Terms

Terms Definition

HW II It is an algorithm used for channel allocationand power control.

HW III It is an algorithm used for power control.

Inband signaling It is the signaling transferred by special bitsin the speech stream.

P/N criterion It is a criteria against which a certainoperation is performed when the criteria lastwithin an acceptable statistical period.

C/I ratio It is the ratio of the strength of a carrier signalto the strength of an interfering signal.




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Terms Definition

Speech version In the GSM communication system, theversions of the speech coding/decodingalgorithms are categorized into full-ratespeech versions 1, 2, and 3 and half-ratespeech versions 1, 2, and 3.

Acronyms and AbbreviationsAcronyms and Abbreviations Full Spelling

AMR Adaptive Multi Rate

RQI Radio Quality Indication

ACS Active Coding Set

C/I Carrier to Interference ratios

11.2 AvailabilityThis lists the NEs and software required for the implementation of AMR. Some specialrequirements are also listed here.

Network Elements InvolvedTable 11-5 describes the NEs involved in AMR.

Table 11-5 NEs involved in AMR

MS BTS BSC MSC MGW SGSN GGSN HLR

√ √ √ √ – – – –

NOTE

l –: NEs not involved

l √: involved

Software ReleasesTable 11-6 describes the versions of GBSS products that support AMR.



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Table 11-6 GBSS products and related versions

Product Version

BSC BSC6000 V900R003C01 and later releases

BTS BTS2X No releases

BTS3001C No releases

BTS3002C No releases

BTS3X G3BTS32V302R002C06 andlater releases

Double-transceiver BTS All releases

NOTE

If the BTS software versions do not meet the mapping requirements, call establishment failure, no audio,or handover failure may occur.

MiscellaneousThe AMR cannot be used unless the following requirements are met.

l The license is available in the BSC.

l The A interface tag of the BSC is PHASE 2+.

l The cell is configured with full-rate speech version 3 or half-rate speech version 3, or both.

l The software versions of the BTS must meet the requirements listed in Table 11-6.

l The MS supports AMR.

NOTE

The MSC determines whether the MS supports AMR based on the Setup message (bearer capabilityIE) reported by the MS.

11.3 Technical DescriptionThis describes the characteristics of the AMR, which allows the BTS and the MS to adjust thecodec rate based on the measured parameters, such as receive level, receive quality, and C/Iratio. An appropriate codec rate can be obtained with the configuration of the AMR call controlparameters in the BSC and the adjustment of the parameters in the MS through the Um interface.In this way, the anti-interference capability and the voice quality in the wireless communicationsystem can be improved.

11.3.1 AMR CallsThis describes the call procedures involved with AMR, such as assignment, incoming inter-BSChandover, outgoing inter-BSC handover, and intra-BSC handover.

11.3.2 AMR Voice Rate AdjustmentThere are two algorithms associated with AMR voice rate adjustment: the static attribute value0 means to adjust data rate by C/I while value 1 means to adjust data rate by BER.




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11.3.3 Algorithm for AMR Intra-Cell Handover Between a Full-Rate TCH and a Half-Rate TCHThis describes the characteristics associated with the handover between a full-rate TCH and ahalf-rate TCH. The algorithm involved is a RQI-based handover decision algorithm targeted forthe AMR call.

11.3.4 AMR Power ControlThis describes the AMR power control associated with HW II and HW III power controlalgorithms.

11.3.5 AMR Channel AssignmentThis describes the channel allocation strategy adopted by the BSC based on the traffic load ofa cell. To balance the capacity and quality within a cell, the half-rate channels should be assignedfirst if allowed when the traffic load of a cell exceeds its threshold.

11.3.1 AMR CallsThis describes the call procedures involved with AMR, such as assignment, incoming inter-BSChandover, outgoing inter-BSC handover, and intra-BSC handover.

The implementation of the call procedures complies with the specifications listed in 11.7References.

Assignment ProcedureThe assignment procedure involves the following aspects:

1. The MSC determines whether an MS supports AMR based on the capability of the MS, theservice type of a call, the speech version supported by the MSC, and the number of thecircuit pool to which the circuits (CIC) on the A interface belong.

2. The MSC determines the speech version set allowed by the call, and then sends the speechversion set to the BSC through the assignment request message.

3. After receiving the Assignment Request message from the MSC, the BSC determineswhether AMR can be used based on whether the license allows the BSC to use AMR andwhether the A interface tag is PHASE 2+.

4. With the speech version set carried in the Assignment Request message and the speechversions supported by the cell, the alternative speech versions are decided.

5. With the alternative speech versions and the channel types actually assigned, the speechversion with highest priority is selected as the resulting speech version for use.

6. If an AMR speech version is selected, the BSC sends the AMR service parameters to theBTS through a channel activation or a mode modify command and to the MS through anassignment command or a channel mode modify command. After the MS is accessed, itreports the assignment complete message to the MSC. The assignment procedure for anAMR call is complete.

Incoming Inter-BSC Handover ProcedureThe incoming inter-BSC handover procedure involves the following aspects:

1. The MSC determines whether an MS supports AMR based on the capability of the MS, theservice type of a call, the speech version supported by the MSC, and the number of thecircuit pool to which the circuits (CIC) on the A interface belong.

2. The MSC determines the speech version set allowed by the call, and then sends the speechversion set to the BSC through the incoming inter-BSC handover request message.



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3. With the speech version set carried in the assignment request message and the speechversions supported by the cell, the alternative speech versions are decided.

4. With the alternative speech versions and the channel types actually assigned, the speechversion with highest priority is selected as the resulting speech version for use.

5. If an AMR speech version is selected, the BSC sends the AMR service parameters to theBTS through a channel activation command. On receiving the channel activationacknowledgment from the BTS, the BSC sends an handover request acknowledgment tothe MSC. The BSC then sends the AMR service parameters to the MS through anassignment command.

Outgoing Inter-BSC Handover ProcedureIn the outgoing inter-BSC handover procedure, the BSC sends a handover request message tothe MSC based on the handover decision algorithm. This message contains the speech versionused by the current call.

Intra-BSC Handover ProcedureIn the intra-BSC handover procedure, the BSC determines to initialize an intra-BSC handoverbased on the BSC handover decision algorithm. According to the saved assignment requests orthe speech version set carried in the incoming BSC handover request, a resulting speech versionis determined with the method adopted by the assignment procedure.

In an AMR call, the BSC sends the AMR service parameters to the BTS through a channelactivation message and to the MS through a handover command.

Determination of the AMR Speech VersionFigure 11-1 shows the procedure for determining the AMR speech version.




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Figure 11-1 Procedure for determining the AMR speech version

The BSC receives anassignment request or a

handover requestsent by the MSC

The list of speech versionssupported by the MSC in themessage saved by the BSC

Whether the licensesupports AMR?

Whether the A interfacetag is PHASEII+?

The set of optional speechversions is obtained based onthe intersection of the speech

versions supported by the MSCand the speech versions

supported by a cell.

Together with the channeltype in actual assignment,

select the speech version whoselevel is the highest and regard it

as the AMR speech versionthat is used finally

A common call

A common call

No

No

Yes

Yes

Start

End

11.3.2 AMR Voice Rate AdjustmentThere are two algorithms associated with AMR voice rate adjustment: the static attribute value0 means to adjust data rate by C/I while value 1 means to adjust data rate by BER.

11.3.3 Algorithm for AMR Intra-Cell Handover Between a Full-RateTCH and a Half-Rate TCH

This describes the characteristics associated with the handover between a full-rate TCH and ahalf-rate TCH. The algorithm involved is a RQI-based handover decision algorithm targeted forthe AMR call.



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Based on the RQI obtained from the BTS uplink measurement, the algorithm determines whetherthe handover between a full-rate TCH and a half-rate TCH in a cell is initiated. The priority ofthe algorithm is lower than that of other handover decision algorithms.

Functional SwitchesThe AMR intra-cell handover between a full-rate TCH and a half-rate TCH is determined byIntracell HO Allowed and Intracell F-H HO Allowed.

RestrictionThe AMR intra-cell handover between a full-rate TCH and a half-rate TCH is subject to thefollowing conditions:l The decision for AMR intra-cell handover between a full-rate TCH and a half-rate TCH is

initiated for only AMR calls.l The half-rate service must be enabled in the cell where the call is located.

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

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

l For full-rate AMR calls, if the AMR TCH/H Prior Allowed is enabled, a handover isallowed only when the cell load is greater than the AMR TCH/H Prior Cell LoadThreshold. For half-rate AMR calls, there is no such a limitation.

Measurement ReportFor AMR calls, the BTS measures the uplink carrier-to-interference ratio and converts it intoRQI. Then, the BTS sends the RQI to the BSC through the measurement report. The conversionformula between RQI and C/I is: RQI = 2 x 10 x log ((C/I)/16). The value ranges from 0 to 72with a unit of 0.5 dB.

Decision AlgorithmsThe algorithm for AMR intra-cell handover between a full-rate TCH and a half-rate TCH followsthe P/N criterion. In a statistical period (indicated by N), if the determination conditions are metfor a period (indicated by P), a handover can be performed.

For an AMR call, when the full-rate TCHs are seized, the handover from a full-rate TCH to ahalf-rate TCH is triggered if the RQI of the call is greater than the F2H HO th in a certain period.When the half-rate TCHs are seized, the handover from a half-rate TCH to a full-rate TCH istriggered if the RQI of the call is smaller than the H2F HO th in a certain period.

Handover ProcedureThe procedure for the AMR intra-cell handover between a full-rate TCH and a half-rate TCH isthe same as the procedure for common handover. The cause value is 0x1F.

11.3.4 AMR Power ControlThis describes the AMR power control associated with HW II and HW III power controlalgorithms.




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In HW II BTS power control algorithm and BSC power control algorithm, the BSC can controlthe AMR calls and the non-AMR calls by setting different power control parameters.

In HW III BSC power control algorithm, the AMR power control differs with the common speechcoding/decoding power control on the setting of the quality threshold parameter. The settingsof the quality threshold parameters for the full-rate AMR call differs with those for the half-rateAMR call.

The AMR speech coding/decoding scheme, with its powerful performance as the commonspeech coding/decoding scheme, can achieve better performance when the C/I ratio is lowerthan normal value. When HW III power control algorithm is used, the AMR quality thresholdis associated with the following parameters:l HWIII DL AFS Rex Qual.Upper Threshold(dB)

l HWIII DL AFS Rex Qual.Lower Threshold(dB)

l HWIII DL AHS Rex Qual.Upper Threshold(dB)

l HWIII DL AHS Rex Qual. Lower Threshold(dB)

11.3.5 AMR Channel AssignmentThis describes the channel allocation strategy adopted by the BSC based on the traffic load ofa cell. To balance the capacity and quality within a cell, the half-rate channels should be assignedfirst if allowed when the traffic load of a cell exceeds its threshold.

When the AMR TCH/H Prior Allowed is set to Yes, and the traffic load of the cell exceedsthe AMR TCH/H Prior Cell Load Threshold, half-rate channels should are assigned first forthe AMR calls.

If the number of TRXs occupied by AMR users exceeds the number of AMR TRXs allowed bylicense, the AMR calls should be assigned to the TRXs that carry the AMR calls for the timebeing to ensure that the number of TRXs occupied by AMR users does not exceeds the thresholdallowed by license.

11.4 CapabilitiesThis describes the functions supported by AMR and the limitations on AMR.

The functions supported by AMR are as follows:

l The full-rate AMR coding/decoding function involves the following speech data rates:– 12.2 kbit/s (GSM EFR)

– 10.2 kbit/s

– 7.95 kbit/s

– 7.40 kbit/s (IS-641)

– 6.70 kbit/s

– 5.90 kbit/s

– 5.15 kbit/s

– 4.75 kbit/s

The full-rate AMR speech codec rate can be adjusted based on the C/I ratio and the ActiveCoding Set (ACS).



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l The half-rate AMR coding/decoding function involves the following speech data rates:– 7.40 kbit/s (IS-641)

– 6.70 kbit/s

– 5.90 kbit/s

– 5.15 kbit/s

– 4.75 kbit/s

The half-rate AMR speech codec rate can be adjusted based on the C/I ratio and the ActiveCoding Set (ACS).

l The AMR supports the HR-FR intra-cell handover based on voice quality.

l Different power control strategies are adopted for AMR calls and non-AMR calls.

l The AMR service can be enabled or disabled on a per cell basis.

l The ACS, codec rate adjustment threshold and hysteresis, and initial codec rate can be seton a per cell basis.

l The AMR configuration, activated ACS, codec rate adjustment threshold and hysteresis,and initial codec rate can be dynamically adjusted.

The limitations on AMR are as follows:

l The activated ACS can be changed during the handover but cannot be changed when achannel is in use.

l The AMR does not support the features such as TFO, RATSCCH, and pre-handover.

l The half-rate AMR service does not support the codec rate at 7.95 kbit/s.

NOTE

In the half-rate mode of the GBSS, the transmission bandwidth over the Abis interface is 8 kbit/s, whichis unable to carry the speech coding information at 7.95 kbit/s. Thus, the 7.95 kbit/s codec rate is notsupported for the half-rate AMR service.

11.5 ImplementationThis describes how to configure, verify, and disable AMR.

11.5.1 Configuring AMRThis describes how to configure AMR on the BSC6000 Local Maintenance Terminal.

11.5.2 Verifying AMRThis describes how to verify AMR on the BSC6000 Local Maintenance Terminal.

11.5.3 Disabling AMRThis describes the how to disable AMR with three methods.

11.5.1 Configuring AMRThis describes how to configure AMR on the BSC6000 Local Maintenance Terminal.

ContextWith Huawei MSC, the BSC should be configured with full-rate speech version 3, half-ratespeech version 3, or both. For detailed configuration, refer to the user manuals related to HuaweiMSC.




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Procedure

Step 1 Apply for and enable the license.1. When applying the licenses of the BSC, ensure that in the BSC6000V900R003 Exceptional

Commercial License Application Template, the Resource number column correspondingto the Number of TRXs supporting AMR in the License control items column is not 0.You should fill in the actual number of TRXs that support AMR.

2. Enable the license on the BSC6000 Local Maintenance Terminal. For details, refer toActivating the BSC License.

Step 2 Set the A interface Tag as GSM_PHASE_2+.1. On the Management Tree tab page of the BSC6000 Local Maintenance Terminal, right-

click BSC6000 and choose Configure BSC Attributes on the shortcut menu. A dialogbox is displayed, as shown in Figure 11-2.

Figure 11-2 Configuring A interface tag of the BSC

2. On the Basic Data tab page, set the A Interface Tag to GSM_PHASE_2+.

Step 3 Set the speech version in a cell to full-rate speech version 3 or half-rate speech version 3.1. Right-click a target cell on the Management Tree of the BSC6000 Local Maintenance

Terminal and choose Configure Cell Attributes on the shortcut menu. A dialog box isdisplayed, as shown in Figure 11-3.



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Figure 11-3 Configuring Cell Attributes dialog box (1)

2. Add the target cell in the Cell view list box to the Selected cells lists box.3. Click Next. A dialog box is displayed, as shown in Figure 11-4.

Figure 11-4 Configuring Cell Attributes dialog box (2)

4. Click Set Cell Properties. A dialog box is displayed, as shown in Figure 11-5




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Figure 11-5 Setting cell attributes

5. Click Call Control. A dialog box is displayed, as shown in Figure 11-6.



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Figure 11-6 Setting call control parameters

6. Click Advanced. A dialog box is displayed, as shown in Figure 11-7.




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Figure 11-7 Setting advanced call control parameters

7. On the Access Control tab page, set the Speech Version to Support Full-rate Version 3.If the cell supports the half-rate service, select Support Half-rate Version 3 simultaneously.

Step 4 Configure the AMR call processing parameters.1. In Figure 11-7, configure the parameters associated with the full-rate and half-rate channels

on the AMR Call Control tab page, as shown in Figure 11-8 and Figure 11-9.

Figure 11-8 Configuring parameters associated with AMR full-rate calls



11-19

Figure 11-9 Configuring parameters associated with AMR half-rate calls

NOTE

One to four coding rates in AMR ACS (F) of Figure 11-8 and AMR ACS (H) of Figure 11-9 canbe selected.

You can select different algorithms by setting AMR Rate Control Switch.

For settings of AFR radio link timeout and AHR radio link timeout, refer to Radio Link Timeout(SACCH period (480ms).

Step 5 Configure parameters associated with full-rate and half-rate handover in AMR cells.1. In Figure 11-5, click Handover Data. A dialog box is displayed, as shown in Figure

11-10. Set the parameters Intracell HO Allowed and Intracell F-H HO Allowed.




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Figure 11-10 Configuring parameters associated with full-rate and half-rate handover inAMR cells

2. Pull down the scroll arrow in Figure 11-10, and set the parameters Intracell F-H HO StartTime(s), Intracell F-H HO Last Time(s), F2H HO th, and H2F HO th.

Step 6 Configure the AMR power control parameters in a cell.1. In Figure 11-5, click Power Control. A dialog box is displayed, as shown in Figure

11-11.



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Figure 11-11 Setting power control parameters





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Figure 11-12 Configuring AMR power control parameters in a cell

3. On the AMR Power Control tab page, configure the parameters listed in AMR PowerControl.

Step 7 Configure the AMR channel management parameters in a cell.1. In Figure 11-5, click Channel Management. A dialog box is displayed, as shown in

Figure 11-13.



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Figure 11-13 Setting channel management parameters





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Figure 11-14 Configuring AMR channel management parameters in a cell

3. On the HWII Channel Assignment and Radio Channel Control tab page, set theparameters AMR TCH/H Prior Allowed and AMR TCH/H Prior Cell LoadThreshold.

Step 8 If a BTS site supports AMR, but its software does not, you should acquire the qualified BTSsoftware versions according to the requirements listed in Table 11-5. For details, refer toMaintaining the BTS. Otherwise, the configuration of AMR will fail.

----End

ExampleEnable the AMR feature in a BTS3X cell that supports half-rate services. A total of 100 TRXsthat support AMR, defined by license. The configuration of AMR parameters is as follows:l Ensure that the software version used in the BTS3X is G3BTS32V302R002C06 or later

releases.l Enable full-rate speech coding algorithm 3 and half-rate speech coding algorithm 3 on the

MSC side.l Enable the AMR license.

l Set A Interface Tag to GSM_PHASE_2+, as shown in Figure 11-2.

l Enable full-rate speech version 3 and half-rate speech version 3 in the cell, as shown inFigure 11-7.

l Configure the AMR call processing parameters in the cell with default values, as shown inFigure 11-8 and Figure 11-9.

l Configure the parameters associated with full-rate and half-rate handover in the AMR cellwith default values, as shown in Figure 11-10.

l Enable full-rate speech version 3 and half-rate speech version 3 in the cell, as shown inFigure 11-7.

l Configure the AMR power control parameters in the cell with default values, as shown inFigure 11-12



11-25

l Configure the AMR channel management parameters in the cell with default values, asshown in Figure 11-5. The configuration is complete.

11.5.2 Verifying AMRThis describes how to verify AMR on the BSC6000 Local Maintenance Terminal.

Prerequisitel The BSC6000 Local Maintenance Terminal is started normally.

l The communication between the BSC and the BTS is normal.

Procedure

Step 1 On the Management Tree of the BSC6000 Local Maintenance Terminal, select the Traceand Monitor tab. On the tab page, choose Trace > Trace User Message . Double-click it. Adialog box is displayed, as shown in Figure 11-15.

Figure 11-15 Trace User Message dialog box

Step 2 Set Interface Type, Tracing Mode, and Color. Specify a user to be traced by IMSI, TMSI,MSISDN, IMEI, or Channel. Click OK to start tracing. The result is displayed, as shown inFigure 11-16.




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Figure 11-16 Trace User Message window

Step 3 Select the area where the CHANNEL ACTIVATION (CHANNEL ACTIVATION aredisplayed in two places in the dialog box. You need select the one near the ASSIGNMENTCOMPLETE.) exists, and then double-click the area. A dialog box is displayed, as shown inFigure 11-17.

Figure 11-17 Displayed result

l If the value of the speech-coding-algor is gsm-speech-coding-algorithm-version(3), itmeans that the AMR is applied.

l Otherwise, the AMR is not applied.

----End



11-27

11.5.3 Disabling AMRThis describes the how to disable AMR with three methods.

PrerequisiteThe AMR is enabled.

Procedurel All the cells controlled by the BSC do not support AMR if the BSC uses the licenses that

do not support AMR.1. Download license.

NOTE

If the license does not support AMR. The value of Number of TRXs supporting AMR in the licensefile should be 0.

2. Activate license.l Set the A Interface Tag to GSM_PHASE_1 or GSM_PHASE_2. All the cells controlled

by the BSC do not support AMR in this case.1. On the BSC6000 Local Maintenance Terminal, right-click BSC6000 on the

Management Tree tab page. Choose Configure TRX Attributes on the shortcutmenu. A dialog box is displayed, as shown in Figure 11-18.

Figure 11-18 Configuring A interface tag of the BSC

2. On the Basic Data tab page, set A Interface Tag to GSM_PHASE_1 orGSM_PHASE_2.

l Disable full-rate speech version 3 and half-rate speech version 3 so that the cell does notsupport AMR.




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1. On the BSC6000 Local Maintenance Terminal, select a cell on the ManagementTree tab page. Right-click the cell, and then select Configure Cell Attributes on theshortcut menu. A dialog box is displayed, as shown in Figure 11-19.

Figure 11-19 Configuring cell attributes

2. Add the target cell in the Cell view list box to the Selected cells lists box.3. Click Next. A dialog box is displayed, as shown in Figure 11-20.



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Figure 11-20 Configuring cell attributes

4. Click Set Cell Properties. A dialog box is displayed, as shown in Figure 11-21




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Figure 11-21 Setting cell attributes

5. Click Call Control. A dialog box is displayed, as shown in Figure 11-22.



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Figure 11-22 Setting call control parameters





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Figure 11-23 Setting advanced call control parameters

7. On the Access Control tab page, adjust Speech Version so that the Value is notSupport Full-rate Version 3 or Support Half-rate Version 3.

8. Click OK to complete the configuration.

----End

11.6 Maintenance InformationThis lists the counters related to AMR.

AlarmsNone.

CountersThe counters related to AMR are listed in Table 11-7, Table 11-8, and Table 11-9.

Table 11-7 Assignment measurement per cell

Counter Description

A3167A Speech Version 3 Completed Assignments(Excluding Directed Retry) (TCHF)

A3168C Speech Version 3 Completed Assignments(Excluding Directed Retry) (TCHH)



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Table 11-8 Intra-cell handover measurement per cell

Counter Description

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)

CH3035A Successful Internal Intra-Cell Handovers(AMR) (TCHF-TCHH)

CH3035B Successful Internal Intra-Cell Handovers(AMR) (TCHH-TCHF)

TH3035A Success Rate of Internal Intra-Cell Handover(AMR) (TCHF-TCHH)

TH3035B Success Rate of Internal Intra-Cell Handover(AMR) (TCHH-TCHF)

Table 11-9 RQI measurement based on TA per TRX

Counter Description

S4400D RQI (TA = 0)

S4401D RQI (TA = 1)

S4402D RQI (TA = 2)

S4403D RQI (TA = 3)

S4404D RQI (TA = 4)

S4405D RQI (TA = 5)

S4406D RQI (TA = 6)




Issue 03 (2008-01-25)

Counter Description

S4407D RQI (TA = 7)

S4408D RQI (TA = 8)

S4409D RQI (TA = 9)

S4410D RQI (TA = 10)

S4411D RQI (TA = 11)

S4413D RQI (TA = 13)

S4414D RQI (TA = 14)

S4415D RQI (TA = 15)

S4416D RQI (TA = 16)

S4417D RQI (TA = 17)

S4418D RQI (TA = 18)

S4419D RQI (TA = 19)

S4420D RQI (TA = 20)

S4421D RQI (TA = 21)

S4422D RQI (TA = 22)

S4423D RQI (TA = 23)

S4424D RQI (TA = 24)

S4425D RQI (TA = 25)

S4426D RQI (TA = 26)

S4427D RQI (TA = 27)

S4428D RQI (TA = 28)

S4429D RQI (TA = 29)

S4430D RQI (TA = 30 or 31)

S4432D RQI (TA = 32 or 33)

S4434D RQI (TA = 34 or 35)

S4436D RQI (TA = 36 or 37)

S4438D RQI (TA = 38 or 39)

S4440D RQI (TA = 40 or 44)

S4445D RQI (TA = 45 or 49)

S4450D RQI (TA = 50 or 54)



11-35

Counter Description

S4455D RQI (TA = 55 or 63)

S4463D RQI (TA greater than 63)

S4400C MRs with RQI (TA = 0)































Issue 03 (2008-01-25)

Counter Description





S4430C MRs with RQI (TA = 30 or 31)









S4463C MRs with RQI (TA greater than 63)

AS4400D Mean RQI (TA = 0)


















11-37

Counter Description















AS4430D Mean RQI (TA = 30 or 31)









AS4463D Mean RQI (TA greater than 63)

11.7 References

l GSM 05.03 V7.3.1 : "Digital cellular telecommunications system (Phase 2+); Channelcoding"

l GSM 05.09 V7.7.1: "Digital cellular telecommunications system (Phase 2+); LinkAdaptation"




Issue 03 (2008-01-25)

l GSM 04.08 V7.21.0: "Digital cellular telecommunications system (Phase 2+); Mobile radiointerface layer 3 specification"

l GSM 06.90 V7.2.1: "Digital cellular telecommunications system (Phase 2+); AdaptiveMulti-Rate (AMR) speech transcoding "

l GSM 06.91 V7.1.1: "Digital cellular telecommunications system (Phase 2+); Substitutionand muting of lost frames for Adaptive Multi Rate (AMR) speech traffic channels "

l GSM 06.92 V7.1.1: "Digital cellular telecommunications system (Phase 2+); Comfortnoise aspects for Adaptive Multi-Rate (AMR) speech traffic channels "

l GSM 06.93 V7.5.0: "Digital cellular telecommunications system (Phase 2+);Discontinuous transmission (DTX) for Adaptive Multi Rate (AMR) speech traffic channels"

l GSM 06.94 V7.1.1: "Digital cellular telecommunications system (Phase 2+); VoiceActivity Detection (VAD) for Adaptive Multi-Rate speech traffic channels "

l GSM 08.08 V7.7.0: "Digital cellular telecommunications system (Phase 2+); Mobile-services Switching Centre - Base Station System (MSC - BSS) interface; Layer 3specification "

l GSM 08.58 V7.4.1: "Digital cellular telecommunications system (Phase 2+); Base StationController - Base Transceiver Station (BSC - BTS) interface; Layer 3 specification "

l GSM 08.60 V7.3.0: "Digital cellular telecommunications system (Phase 2+); In-bandcontrol of remote transcoders and rate adaptors for full rate traffic channels "

l GSM 08.61 V7.3.0: "Digital cellular telecommunications system (Phase 2+); In bandcontrol of remote transcoders and rate adaptors for half rate traffic channels "



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