GPRS EGPRS Channel Management.pdf

7/22/2019 GPRS EGPRS Channel Management.pdf

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GSM BSS

GPRS/EGPRS Channel Management

Feature Parameter Description

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 written consent of Huawei Technologies Co., Ltd.

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

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Page 1 of 24GPRS/EGPRS Channel Management

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Contents1 Introduction

1.1 Scope

1.2 Intended Audience

1.3 Change History

2 Overview3 Technical Description

3.1 Classification of PDCHs

3.2 Allocation of PDCHs

3.2.1 Overview

3.2.2 Preprocessing

3.2.3 Ranking the Priorities of Channel Groups

3.3 Dynamic PDCH Conversion

3.3.1 Overview

3.3.2 Preprocessing

3.3.3 TRX Selection

3.4 Release of Dynamic PDCH

3.4.1 Overview

3.4.2 Rules for Releasing Dynamic PDCH

4 Engineering Guidelines5 Parameters6 Counters7 Glossary8 Reference Documents




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1 Introduction

1.1 Scope

This document describes PDCH allocation algorithm, dynamic PDCH conversion algorithm, and dynamic PDCH release algorithm in the GPRS/EGPRS channel managementfeature.

1.2 Intended Audience

It is assumed that users of this document are familiar with GPRS basics and have a working knowledge of GPRS telecommunication.

This document is intended for:

Personnel working on Huawei GPRS products or systems

System operators who need a general understanding of this feature

1.3 Change History

The change history provides information on the changes in different document versions.

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

Feature change

Feature change refers to the change in the GPRS/EGPRS Channel Management feature of a specific product version.

Editorial change

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

Document Issues

The document issues are as follows:

01 (2010-06-30)

Draft (2010-03-30)

01 (2010-6-30)This is the first release of GBSS12.0.

Compared with issue Draft (2010-03-30) of GBSS12.0, issue 01 (2010-06-30) of GBSS12.0 incorporates the changes described in the following table.

Draft (2010-03-30)

This is the draft release of GBSS12.0.

Change Type Change Description Parameter Change

Featurechange

None. None.

Editorialchange

Parameters are presented inthe form of Parameter IDinstead of Parameter Name.

None.

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2 Overview

This section describes the feature GBFD-113101 PDCH Dynamic Adjustment.

After the GPRS network is deployed, CS services and PS services in the network share channel resources on the Um interface. With operators increasingly preferring PSservices, more and more channel resources on the Um interface are required for PS services. At the same time, to ensure the quality of CS services and PS services, thesystem needs to manage all the PDCHs effectively.

The GPRS/EGPRS Channel Management feature involves the PDCH allocation, dynamic PDCH conversion, and dynamic PDCH release. The PDCH allocation allocates one ormore PDCHs in view of various factors. The dynamic PDCH conversion and dynamic PDCH release adjust PDCHs properly based on the service requirements and actualnetwork conditions. The GPRS/EGPRS Channel Management feature ensures not only the services for one user, but also the performance of the entire network.

During the PDCH allocation process, the principles and requirements for the BSC to select the final channel group vary according to scenarios. Thus, the PDCH allocationalgorithm defines a priority for each channel group. When the MS requests a PDCH, the BSC allocates the channel group with the highest priority to the MS according to theallocation request.

The BSC determines whether to trigger dynamic PDCH conversion based on the PDCH allocation result, rate of idle CS channels, the average load on each PDCH in the cell,and parameter switches. If it is necessary to trigger dynamic PDCH conversion, the BSC converts one or multiple dynamic PDCHs into PDCHs.

If the dynamic PDCH in the PDCH state remains idle for a period of time, the BSC converts it back to the full-rate TCH. When no channel resources or Abis resources areavailable for the CS service, the PDCH preemption procedure is triggered. A dynamic PDCH in the PDCH state is converted into the TCH each time. When the air interfaceresources, DSP resources, and idle timeslot resources are limited, the BSC dynamically releases PDCHs based on dual-threshold.




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3 Technical Description

3.1 Classification of PDCHs

Based on the service support capabilities, PDCHs are classified into the following types:

EGPRS special channel

The EGPRS special channel is allocated only for the EGPRS service.

EGPRS priority channel

The EGPRS priority channel is allocated for the EGPRS service preferentially. When the EGPRS priority channel is not occupied by the EGPRS service, it can be allocated forthe GPRS service.

EGPRS normal channel

The EGPRS normal channel can be allocated for the EGPRS and GPRS services at the same time.

GPRS channel

The GPRS channel is allocated only for the GPRS service.

The EGPRS special channel, EGPRS priority channel, and EGPRS normal channel can be bound with a maximum of four 16 kbit/s Abis timeslots. The GPRS channel can bebound with a maximum of two 16 kbit/s Abis timeslots.

These types of PDCHs can be specified by the parameterGPRSCHPRI on the BSC.

Based on the channel configuration types, PDCHs are classified into the following types:

Static PDCH

The static PDCH carries only PS services. The parameterCHNTYPE is set to PDTCH, PBCCH+PDTCH, or PCCCH+PDTCH.

Dynamic PDCH

The dynamic PDCH carries CS services or PS services depending on the service requirement. It supports only one type of service at the same time. The parameterCHNTYPE is initially set to TCH Full Rate.

3.2 Allocation of PDCHs

3.2.1 Overview

When the uplink and downlink TBFs are not established but there is a data transfer request, the MS sends the PDCH request to the BSC for establishing the uplink TBF. ThePDCH request sent from the MS is classified into the following types:

One phase access on the CCCH and PCCCH

To respond to the PDCH request for one phase access, the BSC allocates one or more PDCHs based on the multislot capability of the MS.

Two phase access on the CCCH and PCCCH

To respond to the PDCH request for two phase access, the BSC allocates only one radio block on the PDCH to the MS for the first time. The MS sends the packet resourcerequest in the allocated radio block. For the second time, the BSC allocates one or multiple PDCHs to the MS based on the multislot capability of the MS.

When the BSC receives the downlink LLC PDUs from the SGSN but no uplink or downlink TBF is available, the network sends the Immediate Assignment message on theCCCH or the Packet Downlink Assignment message on the PCCCH to the BSC for establishing the downlink TBF.

To respond to the Immediate Assignment message on the CCCH, the BSC allocates only one PDCH to the MS.

To respond to the Packet Downlink Assignment message on the PCCCH, the BSC allocates one or multiple PDCHs to the MS based on the multislot capability of the MS.

When the MS is in packet transfer mode, the BSC establishes the uplink or downlink TBF on the PACCH for the MS based on the service requirement. When establishing theuplink or downlink TBF on the PACCH, the BSC allocates one or multiple PDCHs to the MS based on the multislot capability of the MS.

When the MS is in packet transfer mode, the BSC can reallocate the uplink or downlink TBF to the MS based on the service requirement, channel resource change, andmultislot capability of the MS. The BSC can also reallocate the uplink and downlink TBFs to the MS at the same time.

To reallocate only the uplink TBF, the BSC sends the Packet Uplink Assignment message to the MS and allocates PDCHs to the MS.

To reallocate only the downlink TBF, the BSC sends the Packet Downlink Assignment message to the MS and allocates PDCHs to the MS.

To reallocate both the uplink TBF and downlink TBF, the BSC sends the Packet Timeslot Reconfigure message to the MS and allocates PDCHs to the MS.

For details about one phase access on the CCCH/PCCCH, two phase access on the CCCH/PCCCH, downlink TBF establishment on the CCCH/PCCCH, uplink TBFestablishment on the PACCH, downlink TBF establishment on the PACCH, and TBF re-assignment/TS procedure, see the GPRS/EGP RS Connection Control and TransferParameter Description.

3.2.2 Preprocessing

Through PDCH allocation preprocessing, the BSC obtains the information about all PDCHs in the cell that can be allocated to MSs and determines the maximum number ofuplink and downlink PDCHs. This provides a basis for subsequent PDCH allocation.

The BSC obtains the information about all PDCHs in the cell that can be allocated to MSs by excluding the following cases (GBFD-119302 Packet Channel Dispatching):

If the operating status of the PDCH is unavailable or the channel management status is blocked, the PDCH cannot be allocated.

The PDCHs to be released are not allocated to MSs. If there are TBFs on the dynamic PDCHs to be released when PDCH released is due to limited resources, the dynamicPDCHs are marked as PDCHs to be released and are not allocated.

If the number of MSs multiplexed on the PDCH in the uplink x 10 is greater than or equal to PDCHUPLEV, the PDCH cannot be allocated for the uplink PS service.

If the number of MSs multiplexed on the PDCH in the downlink x 10 is greater than or equal to PDCHDWNLEV, the PDCH cannot be allocated for the downlink PS service.

The GPRS channel cannot be allocated for the EGPRS service.

The EGPRS special channel cannot be allocated for the GPRS service.

If the EGPRS priority channel is already allocated for the EGPRS service, it cannot be allocated for the GPRS service.

When the downlink EGPRS and uplink GPRS services share the EGPRS normal channel, the downlink data blocks on this channel must be modulated with GMSK if theGPRS uplink data blocks require scheduling. This may decrease the EGPRS downlink transmission rate. Thus, the downlink EGPRS and uplink GPRS can share the EGPRSnormal channel only when the parameterFORBIDEDGU is set to Open.

The BSC collects statistics on service types dynamically for a period of time by monitoring the uplink and downlink traffic volume of an MS regularly. The service types consist ofthe uplink preferred service, downlink preferred service, and neutral service. The details are as follows:

The BSC monitors the traffic volume of uplink and downlink LLC PDUs of the MS on a regular basis. In a specified monitoring period, if the uplink traffic volume is more thanfive times of the downlink traffic volume, the PS service that the MS operates in the next monitoring period is called the uplink preferred service.

The BSC monitors the traffic volume of uplink and downlink LLC PDUs of the MS on a regular basis. In a specified monitoring period, if the downlink traffic volume is morethan five times the uplink traffic volume, the PS service that the MS processes in the next monitoring period is called the downlink preferred service.

Except the uplink preferred service and downlink preferred service, the PS service that the MS operates in the next monitoring period is called the neutral service.

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The BSC determines the maximum number of uplink and downlink channels that can be allocated to the MS according to the following principles (GBFD-119501 AdaptiveAdjustment of Uplink and Downlink Channels):

For the uplink preferred service, the BSC allocates as many uplink channels as possible.

When SUPPORTEDA is set to SUPPORT, the BSC allocates more than three uplink channels to the MS based on the radio access capability of the MS.

When SUPPORTEDA is set to NOTSUPPORT, the BSC allocates up to two uplink channels to the MS based on the radio access capability of the MS.

For the downlink preferred service, the BSC allocates as many downlink channels as possible.

When SUPPORTDL5TS is set to SUPPORT, the BSC allocates up to five downlink channels to the MS based on the radio access capability of the MS. Otherwise, the BSCallocates up to four downlink channels to the MS based on the radio access capability of the MS.

For the neutral service, the BSC allocates the uplink and downlink channels in a balanced manner.

For example, the BSC allocates three downlink channels and two uplink channels to the MS of multislot class 10.

When SPTDPI is set to SUPPORT, the PDCH identification function is enabled. After identifying the service type, the CN sends the service type to the BSC. Then, the BSCallocates only one downlink channel to the short message service (SMS) according to the service type instead of multislot capability. In this manner, network channel usage isimproved and channel resources are saved. SMS includes Mobile QQ (excluding QQ download and QQ voice service), Fetion, and MSN. After detecting that the subsequentpackets do not carry SMS, the BSC triggers the channel re-allocation procedure. If a subscriber uses several types of services at the same time, for example, the subscriberuses Mobile QQ while browsing websites, the BSC allocates channels required for browsing websites. During the channel re-allocation process, one channel can be convertedinto multiple channels. The reverse conversion, however, is not supported. This avoids the load of channel re-allocation caused by service combination or service handovers.

When PS traffic is heavy in a cell, namely when channel multiplexing ratio (average number of MSs multiplexed on the PDCH in a cell) is higher than the value ofPSServiceBusyThreshold, channels are no longer assigned to new MSs requesting access according to their timeslot capabilities. Instead, only one UL and one DL channelsare assigned to a new MS to ensure its access to the network. In addition, the release delay of all downlink TBFs in the cell is reduced to half the value of DNTBFRELDELAY.Reducing the delay helps prevent new MSs from being denied access to the network due to heavy traffic. Channel assignment to MSs requesting channels again and GBR MSs,however, is not affected. When PS traffic is light in a cell, namely when channel multiplexing ratio is not higher than the value of PSServiceBusyThreshold, channel re-allocation procedure will be triggered to assign channels anew to the new MSs that are assigned one UL and one DL channels if necessary.

3.2.3 Ranking the Priorities of Channel Groups

The PDCH allocation algorithm is based on the priority mechanism. All PDCHs available for allocation in a cell form channel groups, and each channel group is granted apriority. The PDCH allocation algorithm determines whether to select a channel group based on the priority of the channel group. The channel group with high priority isallocated preferentially.

The PDCH allocation algorithm considers many factors during PDCH allocation. Different factors have different impacts on the priorities of channel groups. The factors are listed

as follows in descending order of impact:

MS type (GPRS/EGPRS)

If the MS supports both GPRS and EGPRS, the BSC allocates the EGPRS channel to the MS preferentially.

Band supporting capability of the MS

The BSC allocates only the PDCHs in the bands supported by the MS. When the MS accesses the network for the first time, the BSC allocates only the PDCHs in the BCCHband and the bands compatible with the BCCH to the MS if the BSC is unaware of the radio access capability of the MS. The GSM900 bands compatible with the BCCHconsist of the P-GSM900 band, E-GSM900 band, and R-GSM900 band. The R-GSM900 band consists of the frequencies in the P-GSM900 and E-GSM900 bands, and the E-GSM900 band includes the frequencies in the P-GSM900 band. If the BCCH TRX is configured in the R-GSM900, the E-GSM900 and P-GSM900 are the compatible bands ofthe BCCH. If the BCCH TRX is configured in the E-GSM900, the P-GSM900 is the compatible band of the BCCH. Other frequency bands except GSM900 have nofrequencies in the compatible bands of the BCCH.

Multislot class of the MS

When allocating the PDCHs to the MS, the BSC considers the multislot class of the MS. The BSC supports multislot classes 1 to 45. High multislot classes 35 to 45 aretreated exactly as low multislot classes 8 to 12 respectively. When SUPPORTDL5TS is set to SUPPORT, the BSC supports multislot classes 30 to 34 directly. Otherwise,multislot classes 30 to 34 are treated exactly as multislot classes 8 to 12.

Concentric cell

If the MS is in the coverage area of the underlaid subcell, the BSC allocates only the PDCHs in the underlaid subcell to the MS.

If the MS is in the coverage area of the overlaid subcell, the BSC allocates the PDCHs in the overlaid subcell to the MS preferentially.

Number of Abis timeslots bound with the PDCH

The BSC allocates the PDCH bound with more Abis timeslots to the MS preferentially.

PDCH channel priority type

If the MS requires the EGPRS channel, the BSC allocates the EGP RS special channel, EGPRS priority channel, and EGPRS normal channel in descending order of priorities.

If the MS requires the GPRS channel, the BSC allocates the GPRS channel, EGPRS normal channel, and EGPRS priority channel in descending order of priorities.

Frequency hopping attribute of the PDCH

The BSC allocates the PDCH without frequency hopping to the MS preferentially.

Interference level of the PDCH

The BSC allocates the PDCH with less interference to the MS preferentially.

Whether the PDCH is on the BCCH TRX

The BSC allocates the PDCH on the BCCH TRX to the MS preferentially.

Timeslot number of the PDCH

The BSC allocates the channel group with larger timeslot number to the MS preferentially. The timeslot number of the channel group is the maximum timeslot number of all thechannels in the channel group. If the BSC allocates only one channel to the MS, it allocates the channel in the sequence of timeslot numbers 6, 5, 7, 4, 3, 2, 1, and 0.

3.3 Dynamic PDCH Conversion

3.3.1 Overview

If the BSC does not learn the radio access capability of the MS including the multislot capability of the MS, the BSC converts only one dynamic PDCH. If the BSC learns themultislot capability of the MS, it converts dynamic PDCHs as required. For the MS that uses SMS, the BSC converts only one PDCH instead of converting PDCHs according tothe multislot capability of the MS. If the PDCHs allocated to the MS are insufficient, the BSC triggers dynamic PDCH conversion on the TRX to convert A PDCHs. A =Number ofrequired PDCHs - Number of PDCHs allocated to the MS

Dynamic PDCH conversion is triggered when any of the following conditions are met (GBFD-119303 Load Sharing):

1. IfCHIDLHIGHTHR is set to 100, the BSC triggers dynamic PDCH conversion when the number of MSs carried on the channel reaches UPDYNCHNTRANLEV/10 orDWNDYNCHNTRANLEV.

2. IfCHIDLHIGHTHR is not set to 100, the BSC triggers dual-threshold-based dynamic PDCH conversion when any of the following conditions is met (GBFD-119505 PDCHDynamic Adjustment with Two Thresholds):

The bandwidth of all used PDCHs in the cell is greater than or equal to PDCHGBR, the rate of idle channels in a cell is greater than CHIDLHIGHTHR, and at least onePDCH in the PDCH group allocated for the TBF carries more than one MS.

Among the PDCHs used in the cell, there is at least one PDCH whose bandwidth is less than PDCHGBR, the rate of idle channels in a cell is greater than CHIDLHIGHTHR,and at least one PDCH in the PDCH group allocated for the TBF carries more than B MSs. B is UPDYNCHNTRANLEV/10 or DWNDYNCHNTRANLEV/10.

The rate of idle channels in a cell =number of idle channels in a cell for CS services/number of channels in a cell for CS services x 100%.The type of channels used for CS

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services in a cell is either TCHF or TCHH. A TCHF equals half TCHF. The maximum number of dynamic channels can be converted =(the rate of idle channels in a cell CHIDLHIGHTHR) number of channels in a cell for CS services. The number is the integral number rounded down from the result.

3. The parameter SPTNACCResGuarantee specifies whether the dynamic PDCH conversion based on the guarantee of NACC resources is performed. Guarantee of NACCresources is implemented during NC2 or NACC. If the rate of idle channels in a cell for CS services is greater than CHIDLLOWTHR and the number of idle channels in a cellfor CS services is greater than DYNCHTRANRESLEV, the BSC triggers dynamic PDCH conversion. The maximum number of dynamic channels can be converted =min((therate of idle channels in a cell CHIDLLOWTHR) number of channels in a cell for CS services, (number of idle channels in a cell - DYNCHTRANRESLEV)). The number ofchannels in a cell for CS services is the rounddown integral number.

4. If the rate of idle channels in a cell for CS services is greater than CHIDLLOWTHR and the number of idle channels in a cell for CS services is greater thanDYNCHTRANRESLEV, the BSC triggers dynamic PDCH conversion based on the multislot capability. The maximum number of dynamic channels can be converted =min((the rate of idle channels in a cell CHIDLLOWTHR) number of channels in a cell for CS services, (number of idle channels in a cell - DYNCHTRANRESLEV)). Thenumber of channels in a cell for CS services is the rounddown integral number.

5. The parameter DefaultDynPdchPreTranNum specifies whether the dynamic PDCH conversion based on the pre-conversion is performed. To ensure the proper access of

PS services, you need to set the number of default PDCHs to be converted in the resource pool of dynamic PDCHs of the cell.6. If the EGPRS-capable MS is allocated the GPRS channel and the convertible EGPRS channels are available in the cell, dynamic PDCH conversion is triggered to convert

EGPRS channels as required.

3.3.2 Preprocessing

The PDCH conversion preprocessing is performed to obtain the information about all the convertible dynamic PDCHs in the cell. This provides a basis for the dynamic PDCHconversion.

If the parameter PDCHREFORMING is set to No, only the idle channels can be regarded as candidate channels to participate in dynamic PDCH ranking.

If the parameter PDCHREFORMING is set to Yes, both the dynamic PDCHs occupied by CS services and the idle dynamic PDCHs in the TCH state can be regarded ascandidate channels to participate in dynamic PDCH ranking. If the dynamic PDCHs to be converted already carry CS services, the CS services must be switched to otherchannels in advance.

3.3.3 TRX Selection

The dynamic PDCH conversion algorithm is based on the priority mechanism. All the TRXs with convertible dynamic PDCHs in the cell are granted certain priorities. Thedynamic PDCH conversion algorithm determines whether to select a TRX based on the priority of the TRX.

Table 3-1lists the conditions for selecting preferable TRXs in descending order of priorities.

The factors have different impacts on dynamic PDCH conversion. They are listed in descending order of impacts.

Table 3-1 Condition for selecting preferable TRXs

The method of selecting a TRX according to the conditions listed inTable 3-1 is as follows:

1. All the TRXs in the cell are filtered according to the condition with the highest priority.

If only one TRX meets the condition after filtering, the TRX is selected as the candidate TRX. Then, go to 3.

If multiple TRXs meet the condition, these TRXs are involved in the next round of filtering, as described in 2.

If no TRX meets the condition, all the TRXs are involved in the next round of filtering, as described in step 2.

2. All the TRXs are filtered according to the condition with the priority one level lower.

PRI Condition for SelectingPreferable TRXs

Description

1 Whether the power amplifier ofthe TRX is powered on

If the power amplifier of theTRX is powered on, the TRX ispreferred.

2 Concentric cell attribute of theTRX

If the concentric cell attribute ofthe TRX is consistent with therequired one, the TRX ispreferred.

3 Expansion attribute of the TRX If the expansion attribute of theTRX is consistent with therequired one, the TRX ispreferred.

4 Whether the TRX supportsEGPRS

If the TRX supports EGPRS,the TRX is preferred.

5

Number of convertible dynamicPDCHs on the TRX

If the number of convertibledynamic PDCHs on the TRXmeets the conversionrequirement, the TRX ispreferred.

If the number of convertibledynamic PDCHs on the TRXdoes not meet the conversionrequirement, the TRX with moreconvertible dynamic PDCHshas a higher priority.

6 Number of PDCHs on the TRX The TRX with more PDCHs hasa higher priority.

7 Number of static PDCHs on theTRX

The TRX with more staticPDCHs has a higher priority.

8 Maximum number ofconsecutive convertibledynamic PDCHs on the TRX

The TRX with more consecutiveconvertible dynamic PDCHshas a higher priority.

9 Frequency hopping attribute ofthe TRX

If the TRX is not involved infrequency hopping, the TRX ispreferred.

10 Interference level of the TRX The TRX with less interferencehas a higher priority.

11 Whether the TRX is a BCCHTRX

If the TRX is a BCCH TRX, theTRX is preferred.




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If only one TRX meets the condition after filtering, the TRX is selected as the candidate TRX. Then, go to 3.

If multiple TRXs or no TRX meets the condition, the operation in 2 is repeated. After the corresponding TRXs are filtered, go to 3.

3. The BSC selects the dynamic PDCHs for conversion in the sequence of timeslot numbers 6, 5, 7, 4, 3, 2, 1, and 0.

If the conversion requires channel groups, the BSC selects multiple timeslots for conversion in the sequence of timeslot numbers 6, 5, 7, 4, 3, 2, 1, and 0.

3.4 Release of Dynamic PDCH

3.4.1 Overview

If a dynamic PDCH remains idle for a period of time, the BSC releases it. The idle time is specified by the parameterDYNCHFREETM. If the dynamic PDCH is occupied againby the PS service before the timer expires, the parameterDYNCHFREETM is disabled. After all the TBFs on the dynamic PDCH are released, the parameter DYNCHFREETM

is enabled.

The CS service preempts the dynamic PDCH when no speech channels are available for allocation. If HDLC transmission or IP transmission is applied to the Abis interface, theCS service also preempts the dynamic PDCH when no Abis transmission resources are available.

To improve PS performance, the BSS triggers dual-threshold-based PDCH release when CHIDLHIGHTHR is not set to 100 and air interface resources are limited (GBFD-119505 PDCH Dynamic Adjustment with Two Thresholds).

Dynamic PDCH Release When the A ir Interface Resourc es Are Lim ited

If all the following conditions are met, the BSC triggers dynamic PDCH release when the air interface resources are limited:

The rate of idle channels in a cell is less thanCHIDLLOWTHR or the number of idle channels in a cell for CS services is less than DYNCHTRANRESLEV.

The uplink TBF load in the cell is less thanUPDYNCHNTRANLEV and the downlink TBF load in the cell is less than DWNDYNCHNTRANLEV.

The number of PDCHs in a cell to be allocated to MSs is greater than 4.

If the dynamic PDCH release is triggered owing to insufficient air interface resources, only a PDCH is released at a time.

TBF load is the total number of MSs carried on the channels of a cell.

Dynamic PDCH Release When the DSP Are Limited

The number of PDCHs that can be activated at the same time is limited. When dynamic PDCH conversion fails and PSRESPREEMPT is enabled, the BSS performs dynamicPDCH conversion if the cell whose PDCH conversion fails or the cell with the same DSP distribution meets the following conditions:

The cell where dynamic PDCH conversion fails meets any of the following conditions:

The number of PDCHs in a cell to be allocated to MSs is less than 4.

The uplink TBF load in the cell is greater than UPDYNCHNTRANLEV or the downlink TBF load in the cell is greater than DWNDYNCHNTRANLEV.

The cell with the same DSP distribution must meet the following conditions:

1. The parameterPSRESPREEMPTED is set to YES.

2. The number of PDCHs in a cell to be allocated to MSs is greater than 4.

3. The uplink TBF load in the cell is less than UPDYNCHNTRANLEV and the downlink TBF load in the cell is less than DWNDYNCHNTRANLEV.

If the cells with same DSP distribution meet the previous conditions and release PDCHs, the cell whose dynamic PDCH conversion fails preempts the released PDCHs. If thedynamic PDCH release is triggered owing to insufficient DSP resources, only a PDCH is released at a time.

Dynamic PDCH Release When th e Idle Resources A re Lim ited

The Abis transmission resources are limited. When the cell is idle and PSRESPREEMPT is enabled, the BSS performs dynamic PDCH release if the cell whose idle timeslotapplication fails and other cells in the BSS meet the following conditions:

If the cell where assigning idle timeslots fails meets any of the following conditions:

1. The parameterPSRESPREEMPTED is set to YES.2. The uplink TBF load in the cell is less than UPDYNCHNTRANLEV or the downlink TBF load in the cell is less than DWNDYNCHNTRANLEV.

3. The bandwidth of the cell whose PDCH application fails is less thanPDCHGBR.

If other cells in the BSS meet the following conditions:

1. The parameterPSRESPREEMPTED is set to YES.

2. The uplink TBF load in the cell is less than UPDYNCHNTRANLEV and the downlink TBF load in the cell is less than DWNDYNCHNTRANLEV.

3. The number of PDCHs in a cell to be allocated to MSs is greater than 4.

If other cells in the BSS meet the previous conditions and release PDCHs, the cell whose idle timeslot application fails preempts the released PDCHs. If the dynamic PDCHrelease is triggered owing to insufficient idle timeslots, only a PDCH is released at a time.

3.4.2 Rules for Releasing Dynamic PDCH

The dynamic PDCH is released when the CS service preempts it or when the resources are limited. If the dynamic PDCH is released because the CS service preempts it, thefactors listed inTable 3-2must be taken into account. These factors are listed in descending order of priorities. If the dynamic PDCH is released because the resources arelimited, the factors listed inTable 3-3 must be taken into account. These factors are listed in descending order of priorities.

Table 3-2 Factors taken into account when the dynamic PDCH is released because the CS service preempts it

Priority Factor Description

1 Frequency band If the frequency band of thedynamic PDCH is not the onerequired by the CS service, thedynamic PDCH cannot bereleased.

2 Concentric cell If the required concentric cellattribute is only underlaidsubcell or only overlaid subcelland the position of the dynamicPDCH in the concentric celldoes not meet the preemptionrequirement, the dynamicPDCH cannot be released.

If the required concentric cellattribute is underlaid subcellpreferred or overlaid subcell

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Table 3-3 Factors taken into account when the dynamic PDCH is released because the resources are limited

preferred and the position of thedynamic PDCH in theconcentric cell meets thepreemption requirement, thedynamic PDCH is releasedpreferentially.

3 Whether the dynamic PDCH isidle

If the dynamic PDCH is idle, it isreleased preferentially.

4 Whether the dynamic PDCH ismarked as the PDCH to bereleased

The dynamic PDCH marked asthe PDCH to be released hashigher priority.

5 Number of multiplexed MSs

using the dynamic PDCH as thecontrol channel

IfDYNCHNPREEMPTLEV is

set to No preempt of CCHsand at least one MS uses thedynamic PDCH as the controlchannel, the dynamic PDCHcannot be released.

6 Number of multiplexed MSs onthe dynamic PDCH

IfDYNCHNPREEMPTLEV isset to No preempt of serviceTCHF and at least an MS usesthe dynamic PDCH, the PDCHcannot be released.

IfDYNCHNPREEMPTLEV isset to Preempt all dynamicTCHFs , the number of dynamicPDCHs used as controlchannels has a negativecorrelation with the priority ofdynamic PDCH preemption.

IfDYNCHNPREEMPTLEV isset to Preempt all dynamicTCHFs orNo preempt of

CCHs, the number ofmultiplexed MSs on thedynamic PDCH has a negativecorrelation with the priority ofdynamic PDCH preemption.

7 Number of static PDCHsconfigured on the TRX of thedynamic PDCH

The number of static PDCHsconfigured on the TRX of thedynamic PDCH has a negativecorrelation with the priority ofdynamic PDCH release.

8 Number of PDCHs on the TRXof the dynamic PDCH

The number of PDCHs on theTRX of the dynamic PDCH hasa negative correlation with thepriority of dynamic PDCHrelease.

9 PDCH priority type of thedynamic PDCH

The BSC releases the GPRSchannel, EGPRS normalchannel, and EGPRS prioritychannel in descending order ofpriorities.

10 Timeslot number of the dynamicPDCH

The BSC releases the dynamicPDCHs in the sequence oftimeslot numbers 0, 1, 2, 3, 4,7, 5, and 6.

Priority Factor Description

1 Whether the dynamic PDCH ispre-converted into PDCH

If the dynamic PDCH is pre-converted PDCH, the PDCH ismarked as the PDCH not to bereleased. The priority of non-pre-converted PDCH is higherthan pre-converted PDCHrelease.

2 Whether the dynamic PDCH isidle

If the dynamic PDCH is idle, it isreleased preferentially.

3 Number of multiplexed MSsusing the dynamic PDCH as thecontrol channel

If an MS uses the dynamicPDCH as the control channel,the channel cannot be released.

4 Number of multiplexed MSs onthe dynamic PDCH

The number of multiplexed MSsusing the dynamic PDCH has anegative correlation with thepriority of dynamic PDCHrelease.

5 Number of static PDCHsconfigured on the TRX of thedynamic PDCH

The number of static PDCHsconfigured on the TRX of thedynamic PDCH has a negativecorrelation with the priority ofdynamic PDCH release.

6 Number of PDCHs on the TRXof the dynamic PDCH

The number of PDCHs on theTRX of the dynamic PDCH hasa negative correlation with thepriority of dynamic PDCHrelease.




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To select a dynamic PDCH, perform the following steps:

1. All the dynamic PDCHs in the cell are filtered according to the condition with the highest priority.

If only one dynamic PDCH meets the condition after filtering, the dynamic PDCH is selected as the candidate PDCH.

If multiple dynamic PDCHs meet the condition, these dynamic PDCHs are involved in the next round of filtering, as described in 2.

If no dynamic PDCH meets the condition, all the dynamic PDCHs are involved in the next round of filtering, as described in 2.

2. All the dynamic PDCHs are filtered according to the condition with the priority one level lower.

If only one dynamic PDCH meets the condition after filtering, the dynamic PDCH is selected as the candidate PDCH.

If multiple dynamic PDCHs meet the condition, the operation in2 is repeated until the corresponding dynamic PDCH is selected.

7 PDCH priority type of thedynamic PDCH

The BSC releases the GPRSchannel, EGPRS normalchannel, and EGPRS prioritychannel in descending order ofpriorities.

8 Timeslot number of the dynamicPDCH

The BSC releases the dynamicPDCHs in the sequence oftimeslot numbers 0, 1, 2, 3, 4,7, 5, and 6.




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4 Engineering Guidelines

Cell

The maximum number of PDCHs in a cell is restricted by the setting ofMAXPDCHRATE.

Maximum number of PDCHs in a cell =(Number of static PDCHs +Number of dynamic PDCHs) Maximum Ratio Threshold of PDCHs in a Cell

The BSC does not perform dynamic PDCH conversion to reserve idle channel resources for the CS service, thus reducing the impact on the CS service. The number of reservedidle channels is set to DYNCHTRANRESLEV.

TRX

If a TRX is configured with several static PDCHs, it is recommended that the static PDCHs be configured in the sequence of timeslot numbers 6, 5, 7, 4, 3, 2, 1, and 0.

The setting ofGPRSCHPRI should be the same for all the PDCHs on a TRX.

If the GPRS and EGPRS services need to be isolated on a TRX, it is recommended that the EGPRS special channel, EGPRS priority channel, EGPRS normal channel, andGPRS channel be configured in the sequence of timeslot numbers 6, 5, 7, 4, 3, 2, 1, and 0.

The maximum number of PDCHs on a TRX is determined byMAXPDCHNUM.

Multiband Network

In a multiband cell, it is recommended that the static PDCH be configured in the BCCH band and the bands compatible with the BCCH.

Concentric Cell

IfIUOCHNTRAN is set to CONVERT0(Only convert at UL) or CONVERT2(UL first and convert allowed), it is recommended that the static PDCH be configured on theunderlaid subcell.

IfIUOCHNTRAN is set to CONVERT1(Only convert at OL) orCONVERT3(OL first and convert allowed), it is recommended that the static PDCH be configured on theoverlaid subcell.

If the BCCH is configured on the TRX in the underlaid subcell, it is recommended that the parameter IUOCHNTRAN be set to CONVERT0(Only convert at UL).

If the BCCH is configured on the TRX in the overlaid subcell, it is recommended that the parameter IUOCHNTRAN be set to CONVERT1(Only convert at OL).




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5 Parameters

Table 5-1 Parameter description

Parameter ID NE MML Description

GPRSCHPRI BSC6900SET GTRXCHAN(Optional) Meaning: EGPRS prioritytype of the channelIf this parameter is set toGPRS, the EDGE MSscannot use this channel.If this parameter is set toEGPRSNORCH, theGPRS and EDGE MSscan use this channel atthe same priority.If this parameter is set toEGPRSPRICH, theEDGE MSs have thepriority to use thischannel.If this parameter is set toEGPRSSPECH, only theEDGE MSs can use thischannel.If this parameter is set toNONGPRS, thisparameter becomesinvalid.

GUI Value Range: GPRS(GPRS Channel),EGPRSNORCH(EGPRSNormal Channel),

EGPRSPRICH(EGPRSPriority Channel),EGPRSSPECH(EGPRSSpecial Channel),NONGPRS(Non-GPRSChannel)Actual Value Range:GPRS, EGPRSNORCH,EGPRSPRICH,EGPRSSPECH,NONGPRSUnit: NoneDefault Value: NONGPRS

CHNTYPE BSC6900SET BTSCHNFALLBACK(Mandatory)

Meaning: Channel type ofthe timeslot on the TRX.

The channel type oftimeslot 0 must not beset, because thecombined BCCH isconfigured by default. Thechannel type of othertimeslots can be set tofull-rate TCH or half-rate

TCH.

GUI Value Range:FULLTCH(FULLTCH),HALFTCH(HALFTCH)Actual Value Range:FULLTCH, HALFTCHUnit: NoneDefault Value: None

PDCHUPLEV BSC6900SET GCELLPSCHM(Optional) Meaning: PDCH uplinkmultiplex threshold,indicating the maximum

TBFs on the uplink PDCH(parameter value/10). Werecommend that the valueof "Uplink Multiplex

Threshold of DynamicChannel Conversion"should be less than"PDCH Uplink Multiplex

Threshold" for triggeringconverting dynamicchannel in time andreducing PDCH multiplex.GUI Value Range: 10~70Actual Value Range:10~70Unit: NoneDefault Value: 70

PDCHDWNLEV BSC6900SET GCELLPSCHM(Optional) Meaning: PDCH downlinkmultiplex threshold,Indicating the maximum

TBFs on the downlinkPDCH (parameter




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value/10). Werecommend that the valueof "Downlink Multiplex

Threshold of DynamicChannel Conversion"should be less than"PDCH DownlinkMultiplex Threshold" fortriggering convertingdynamic channel in timeand reducing PDCHmultiplex.

GUI Value Range:10~160Actual Value Range:10~160Unit: NoneDefault Value: 80

FORBIDEDGU BSC6900SET BSCPSSOFTPARA(Optional) Meaning: Switchspecifying whether toallow the downlinkEGPRS TBF and theuplink GPRS TBF toshare the same channel.On: allow the downlinkEGPRS TBF and theuplink GPRS TBF toshare the same channel;Off: prohibit the downlinkEGPRS TBF and theuplink GPRS TBF sharingthe same channel.

GUI Value Range: OPEN(Open), CLOSE(Close)Actual Value Range:OPEN, CLOSEUnit: NoneDefault Value: OPEN

SUPPORTEDA BSC6900SET BSCPSSOFTPARA(Optional) Meaning: Whether tosupport EDA. Extendeddynamic allocation (EDA)enables the MS to beallocated with moretimeslots on the uplink,thus improving the uplinkrate and helping totransmit large amounts ofdata on the uplink.

GUI Value Range:NOTSUPPORT(NotSupport), SUPPORT(Support)Actual Value Range:NOTSUPPORT,SUPPORTUnit: NoneDefault Value:NOTSUPPORT

SUPPORTDL5TS BSC6900SET BSCPSSOFTPARA(Optional) Meaning: Whether tosupport the high multislotclass. High multislot classfunction enables a singleMS to be allocated with amaximum of five timeslotson the uplink or downlink,thus improving the uplinkor downlink throughput ofa single MS. The BSSsupports the MS with highmultislot classes from 30to 34. A maximum of fivetimeslots on the downlink

can be assigned to anMS. If an MS is of thehigh multislot class 34, amaximum of five timeslotson the uplink can beallocated to the MS. Thus,the uplink and downlinkthroughput is increasedby 25%.The total numberof timeslots on the uplinkand downlink cannotexceed six. That is, if fivetimeslots on the downlinkare allocated to the MS,then only one timeslot onthe uplink can beallocated to the MS.




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GUI Value Range:NOTSUPPORT(NotSupport), SUPPORT(Support)Actual Value Range:NOTSUPPORT,SUPPORTUnit: NoneDefault Value:NOTSUPPORT

SPTDPI BSC6900SET GCELLGPRS(Optional) Meaning: The parameterspecifies whether the cellcan identify the types ofPS services. Byidentifying the types of PSservices, the BSC canproperly manage radioresource.

GUI Value Range:UNSUPPORT(NotSupport), SUPPORT(Support)Actual Value Range:UNSUPPORT,SUPPORTUnit: NoneDefault Value:UNSUPPORT

CHIDLHIGHTHR BSC6900SET GCELLPSCHM(Optional) Meaning: When thechannel is multiplexed bymore than one user andthe idle channel rate is

above this parameter, adynamic channelconversion request israised.

The CS idle channel ratecan be calculated asfollows:CS Idle channel rate =Idle cell channels for CSservice/Available cellchannels for CS service x100%.Here, available cellchannels refer to thenumber of available

TCHFs or TCHHs in acell.Idle cell channels refer tothe number of the TCHFsor TCHHs that do notcarry any CS service datain a cell.

Two TCHHs areconsidered as one TCHF.

When this parameter isset to "100", it is invalid.

GUI Value Range: 0~100Actual Value Range:0~100Unit: %Default Value: 100

UPDYNCHNTRANLEV BSC6900SET GCELLPSCHM(Optional) Meaning: Controlschannel conversionrequests and releasesaccording to cell loadMaximum number of theusers multiplexing onechannel, which is a triggercondition for the uplinkdynamic channel

transition. When "UpperThreshold for CS IdleChannel Rate" is set to"100" and the number ofthe users multiplexing onechannel reaches "UplinkMultiplex Threshold ofDynamic ChannelConversion"/10, therequest for channelconversion is triggered.When channel bandwidthis not greater than "PSService Guaranteed Rate"set through the "SETBTSOTHPARA"command, a channelconversion request is




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raised if the CS idlechannel rate is above"Upper Threshold for CSIdle Channel Rate" andthe number of userscarried on the channelreaches "Uplink Multiplex

Threshold of DynamicChannel Conversion"/10.When "Upper Thresholdfor CS Idle Channel Rate"is not set to "100", if theCS idle channel rate is

below "Lower Thresholdfor CS Idle Channel Rate"and the number of theusers multiplexing onechannel is smaller than"Uplink Multiplex

Threshold of DynamicChannel Conversion"/10,the related channel isreleased.In the case of insufficientAbis or DSP resources,the resources of othercells can be preemptedonly when the cell load ishigher than "UplinkMultiplex Threshold ofDynamic ChannelConversion"/10.Resources and channelscan be released only

when the cell load islower than "UplinkMultiplex Threshold ofDynamic ChannelConversion"/10. Werecommend that the valueof "Uplink Multiplex

Threshold of DynamicChannel Conversion"should be less than"PDCH Uplink Multiplex

Threshold" for triggeringconverting dynamicchannel in time andreducing PDCH multiplex.GUI Value Range: 10~70Actual Value Range:10~70Unit: NoneDefault Value: 20

DWNDYNCHNTRANLEV BSC6900SET GCELLPSCHM(Optional) Meaning: Controlschannel conversionrequests and releasesaccording to cell loadMaximum number of theusers multiplexing onechannel, which is a triggercondition for the downlinkdynamic channeltransition. When "Upper

Threshold for CS IdleChannel Rate" is set to"100" and the number ofthe users multiplexing onechannel reaches"Downlink Multiplex

Threshold of DynamicChannel conversion"/10,the request for channelconversion is triggered.When channel bandwidth

is not greater than "PSService Guaranteed Rate"set through the "SETBTSOTHPARA"command, a channelconversion request israised if the CS idlechannel rate is above"Upper Threshold for CSIdle Channel Rate" andthe number of userscarried on the channelreaches "DownlinkMultiplex Threshold ofDynamic ChannelConversion"/10.When "Upper Threshold




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for CS Idle Channel Rate"is not set to "100", If theCS idle channel rate isbelow "Lower Thresholdfor CS Idle Channel Rate"and the number of theusers multiplexing onechannel is smaller than"Downlink Multiplex

Threshold of DynamicChannel Conversion"/10.In the case of insufficientAbis or DSP resources,

the resources of othercells can be preemptedonly when the cell load ishigher than "DownlinkMultiplex Threshold ofDynamic ChannelConversion"/10.Resources and channelscan be released onlywhen the cell load islower than "DownlinkMultiplex Threshold ofDynamic ChannelConversion"/10. Werecommend that the valueof "Downlink Multiplex

Threshold of DynamicChannel Conversion"should be less than"PDCH DownlinkMultiplex Threshold" for

triggering convertingdynamic channel in timeand reducing PDCHmultiplex.

GUI Value Range: 10~80Actual Value Range:10~80Unit: NoneDefault Value: 20

PDCHGBR BSC6900SET BTSOTHPARA(Optional) Meaning: Minimumnumber of Abis resourcesrequested for PSchannels in the site.When this parameter isset to 16K, a minimum of16 kbit/s bandwidth isrequired for this channel.When this parameter isset to 32K, a minimum of32 kbit/s bandwidth is

required for this channel.When this parameter isset to 48K, a minimum of48 kbit/s bandwidth isrequired for this channel.When this parameter isset to 64K, a minimum of64 kbit/s bandwidth isrequired for this channel.

To handle services on thechannel at a great codingscheme as soon aspossible, you need to setthis parameter to a greatvalue.

GUI Value Range: 16K(16K), 32K(32K), 48K(48K), 64K(64K)Actual Value Range: 16K,32K, 48K, 64K

Unit: bit/sDefault Value: 16K

SPTNACCResGuarantee BSC6900SET BSCPSSOFTPARA(Optional) Meaning: Whether thefunction of NetworkAssisted Cell Change(NACC) resourceguarantee is allowed. InNC2 or NACC cellreselection, if thisparameter is set to YES,dynamic channels arerequested in the targetcell.

GUI Value Range: NO(NO), YES(YES)Actual Value Range: NO,




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YES Unit: NoneDefault Value: NO

CHIDLLOWTHR BSC6900SET GCELLPSCHM(Optional) Meaning: When the CSidle channel rate is belowthis threshold, a dynamicchannel can be released.

The CS idle channel ratecan be calculated asfollows:CS Idle channel rate =Idle cell channels for CSservice/Available cellchannels for CS service x100%.Here, available cellchannels refer to theavailable TCHFs or

TCHHs in a cell.Idle cell channels refer tothe TCHFs or TCHHs thatdo not carry any CSservices data in a cell.

Two TCHHs areconsidered as one TCHF.When "Upper Thresholdfor CS Idle Channel Rate"is set to "100", it is invalid.GUI Value Range: 0~100Actual Value Range:0~100Unit: %Default Value: 10

DYNCHTRANRESLEV BSC6900SET GCELLPSCHM(Optional) Meaning: Number of full-rate TCHs reserved forthe CS domain

GUI Value Range: 0~8Actual Value Range: 0~8Unit: NoneDefault Value: 2

DefaultDynPdchPreTranNumBSC6900SET GCELLPSCHM(Optional) Meaning: This parameterspecifies the default pre-converted PDCHs in thedynamic transferablechannel pool.When this parameter isgreater than 0, three sub-links are bound to thestatic PDCH and pre-converted PDCH in a cellby default.

The pre-converted PDCH

can be preempted when itis idle. You can set"Number of ReservedDynamic Channel" asrequired when you expectthe pre-converted PDCHnot to be preempted.

GUI Value Range: 0~32Actual Value Range:0~32Unit: NoneDefault Value: 0

PDCHREFORMING BSC6900SET GCELLPSCHM(Optional) Meaning: This parametermust be used togetherwith "Level of PreemptingDynamic Channel" in thefollowing conditions:1. When "Level ofPreempting DynamicChannel" is set to "No

preempt of service TCHF"and "PDCH Reforming" isset to "Yes", the channelsfor the CS service isreleased if the CS servicefails to be switched toanother channel.2: When "Level ofPreempting DynamicChannel" is set to"Preempt all dynamic

TCHFs" or "No preemptof CCHs" and "PDCHReforming" is set to"Yes", the CS service isswitched to the originalchannel if the CS service




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fails to be switched toanother channel.

GUI Value Range: NO(NO), YES(YES)Actual Value Range: NO,


DYNCHFREETM BSC6900SET GCELLPSCHM(Optional) Meaning: Time to wait forreleasing the dynamicchannel after the TBF onthe dynamic channel isreleased. When all the

TBFs on the channel arereleased, the dynamicchannel is not released atonce. Instead, the timer isstarted when thechannels are idle. Beforethe timer expires, if newservice request isreceived, the dynamicchannel is still occupiedand timer is stopped;otherwise, the dynamicchannel is released afterthe timer expired.

GUI Value Range:10~3600Actual Value Range:10~3600Unit: s

Default Value: 20

PSRESPREEMPT BSC6900SET GCELLPSCHM(Optional) Meaning: Determineswhether the PS resourcesin other cells can bepreempted when the PSresources are insufficientin the current cell.

GUI Value Range: NO(No), YES(Yes)Actual Value Range: NO,


PSRESPREEMPTED BSC6900SET GCELLPSCHM(Optional) Meaning: Determineswhether the PS resourcesin the current cell can bepreempted, to ensure thePS services in other cells.

GUI Value Range: NO(No), YES(Yes)Actual Value Range: NO,


DYNCHNPREEMPTLEV BSC6900SET GCELLPSCHM(Optional) Meaning: Mode ofpreempting the dynamicchannel for the CSdomain and PS domain.Only the channelconfigured in the TCH/Fmode can be preempted."Preempt all dynamic

TCHFs" indicates thecircuit domain canpreempt all the dynamicchannels."No preempt of CCHs"indicates the circuitdomain can preempt all

the dynamic channelsexcept the CCHs."No preempt of service

TCHF" indicates thecircuit domain cannotpreempt all the dynamicchannels of bearerservices.

GUI Value Range:LEVEL0(Preempt alldynamic TCHFs),LEVEL1(No preempt ofCCHs), LEVEL2(Nopreempt of service TCHF)Actual Value Range:LEVEL0, LEVEL1,




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LEVEL2Unit: NoneDefault Value: LEVEL0

MAXPDCHRATE BSC6900SET GCELLPSCHM(Optional) Meaning: Maximum valueof the PDCH ratio in acell. The number ofavailable TCHs andPDCHs in a cell is set to afixed value. The PDCHratio is: Number ofavailable PDCHs/(Number of available

TCHFs +Number ofavailable static PDCHs).

This parameter is used torestrict the PDCH ratio.

GUI Value Range: 0~100Actual Value Range:0~100Unit: %Default Value: 30

MAXPDCHNUM BSC6900SET GTRXBASE(Optional) Meaning: Maximumnumber of PDCHs thatcan be assigned in the

TRX

GUI Value Range: 0~8Actual Value Range: 0~8Unit: NoneDefault Value: 8

IUOCHNTRAN BSC6900SET GCELLPSCHM(Optional) Meaning: Conversionpolicy of the dynamic

channel of the concentriccell

GUI Value Range:CONVERT0(Only convertat UL), CONVERT1(Onlyconvert at OL),CONVERT2(UL first andconvert allowed),CONVERT3(OL first andconvert allowed)Actual Value Range:CONVERT0,CONVERT1,CONVERT2, CONVERT3Unit: NoneDefault Value:CONVERT0

PSServiceBusyThreshold BSC6900SET GCELLPSCHM(Optional) Meaning: Threshold of theaverage number of MSsmultiplexed on each

PDCH in a cell. When theaverage number of MSsmultiplexed on eachPDCH in a cell is greaterthan this threshold, thePS traffic volume in thecell is considered to behigh. In this case, eachnewly admitted MS isassigned only one PDCH.When the PS trafficvolume is not high, theMS with only one PDCHis re-assigned a certainnumber of PDCHs asrequired.

GUI Value Range:10~160Actual Value Range:10~160

Unit: NoneDefault Value: 80

DNTBFRELDELAY BSC6900SET GCELLPR IVATEOPTPARA(Optional)

Meaning: Delay ofreleasing the downlink

TBF. After the lastdownlink RLC data blockis transmitted on thenetwork side and all thetransmitted downlink datablocks are received, theMS is not informed to stopthis downlink TBF.Instead, the state of thelast data block is forciblyset to "not received" andthe RRBP flag of the lastdata block is




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retransmittedcontinuously so that thedownlink TBF is notreleased. During thedownlink delay release, ifthe upper layer of thenetwork side needs totransmit downlink data,the downlink RLC blockfor unpacking can betransmitted in thedownlink TBF for delayrelease. The state of the

downlink TBF is changedfrom delay releasing todownlink transmitting. Inaddition, the MS mustrespond to the PacketDownlink Ack/Nackmessage through theuplink data block of theRRBP to exchangemessages with thenetwork side. When theMS needs to send data,the MS can send theuplink request to thenetwork sides through thePacket DownlinkAck/Nack with thechannel requestdescription. If thisparameter is set to 0, therelease delay of downlink

TBF is disabled.

GUI Value Range:0~5000Actual Value Range:0~5000Unit: msDefault Value: 2400




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6 Counters

For the counters, see the BSC6900 GSM Performance Counter Reference.




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7 Glossary

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




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8 Reference Documents

3GPP TS 44.060 "Mobile Station (MS) - Base Station System (BSS) interface; Radio Link Control/Medium Access Control (RLC/MAC) protocol"

3GPP TS 44.018 "Base Station System (BSS) - Serving GPRS Support Node (SGSN); BSS GPRS Protocol (BSSGP )"

3GPP TS 45.002 "Radio Access Network; Multiplexing and multiple access on the radio path"

3GPP TS 24.008, 3GPP TS 48.018, and 3GPP TS 48.016 peer layer protocols between the BSS and the SGSN

BSC6900 Feature List

BSC6900 Optional Feature Description

GBSS Reconfiguration Guide

BSC6900 GSM Parameter Reference

BSC6900 GSM MML Command Reference

BSC6900 Performance Counter Reference

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Date post:	10-Feb-2018
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