idle mode behavior

Idle Mode Behavior Feature Parameter Description

Copyright © Huawei Technologies Co., Ltd. 2010. All rights reserved.

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

Issue 02 (2009-09-30) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd. i

BSS Idle Mode Behavior Contents

Issue 02 (2009-09-30) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd.

iii

Contents 1 Introduction to This Document .............................................................................................1-1

1.1 Scope ............................................................................................................................................ 1-1 1.2 Intended Audience ........................................................................................................................ 1-1 1.3 Change History.............................................................................................................................. 1-1

2 Overview .....................................................................................................................................2-1

3 Technical Description ..............................................................................................................3-1 3.1 Overview ....................................................................................................................................... 3-1 3.2 PLMN Selection............................................................................................................................. 3-2

3.2.1 Overview............................................................................................................................... 3-2 3.2.2 Automatic PLMN Selection Mode......................................................................................... 3-2 3.2.3 Manual PLMN Selection Mode............................................................................................. 3-2

3.3 GSM Cell Selection ....................................................................................................................... 3-2 3.3.1 Overview............................................................................................................................... 3-2 3.3.2 Conditions for Normally Camping on a Cell ......................................................................... 3-3 3.3.3 Cell Selection Criterion......................................................................................................... 3-3

3.4 GSM Cell Reselection ................................................................................................................... 3-4 3.4.1 Overview............................................................................................................................... 3-4 3.4.2 Conditions for Triggering Cell Reselection ........................................................................... 3-4 3.4.3 Cell Reselection Algorithms.................................................................................................. 3-5

3.5 Location Area Update.................................................................................................................... 3-6 3.5.1 Overview............................................................................................................................... 3-6 3.5.2 Location Area........................................................................................................................ 3-7 3.5.3 Normal Location Area Update .............................................................................................. 3-8 3.5.4 IMSI Attach/Detach............................................................................................................... 3-8 3.5.5 Periodic Location Area Update............................................................................................. 3-8

3.6 Control Channels........................................................................................................................... 3-9 3.7 Paging ......................................................................................................................................... 3-10

3.7.1 Overview............................................................................................................................. 3-10 3.7.2 CCCH Configuration and Paging Group Calculation ......................................................... 3-10 3.7.3 CS Paging .......................................................................................................................... 3-11 3.7.4 PS Paging........................................................................................................................... 3-12 3.7.5 Paging Modes..................................................................................................................... 3-12 3.7.6 Paging Functions................................................................................................................ 3-12

3.8 System Information ..................................................................................................................... 3-14 3.8.1 Overview............................................................................................................................. 3-14 3.8.2 System Information Type 1................................................................................................. 3-14 3.8.3 System Information Types 2, 2BIS, 2TER, and 2QUATER................................................ 3-17 3.8.4 System Information Type 3................................................................................................. 3-20 3.8.5 System Information Type 4................................................................................................. 3-22

Contents BSS

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3.8.6 System Information Type 7................................................................................................. 3-23 3.8.7 System Information Type 8................................................................................................. 3-23 3.8.8 System Information Type 13............................................................................................... 3-24

3.9 Short Message Service Cell Broadcast....................................................................................... 3-24 3.10 Public Voice Group Call Service ............................................................................................... 3-25

3.10.1 Overview........................................................................................................................... 3-25 3.10.2 System Information........................................................................................................... 3-25

4 Parameters .................................................................................................................................4-1

5 Counters......................................................................................................................................5-1

6 Glossary ......................................................................................................................................6-1

7 Reference Documents .............................................................................................................7-1

BSS Idle Mode Behavior 1 Introduction to This Document


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1 Introduction to This Document 1.1 Scope This document describes the behavior of the MS in idle mode and of the network. The behavior includes the procedures of public land mobile network (PLMN) selection, cell selection, cell reselection, location area update, paging, and cell broadcast. This document also describes control channels and system information.

1.2 Intended Audience It is assumed that users of this document are familiar with GSM basics and have a working knowledge of GSM telecommunication.

This document is intended for:

Personnel working on Huawei GSM products or systems System operators who need a general understanding of this feature

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

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

Feature change Feature change refers to the change in the Idle Mode Behavior 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 (2009-11-20)

01 (2009-11-20) This is the first commercial release of GBSS9.0.

BSS Idle Mode Behavior 2 Overview


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2 Overview An MS that is switched on but is not allocated a dedicated channel is defined as an MS in idle mode. An MS in idle mode can access the network and can be reached by the network.

When an MS is switched on, it attempts to select a PLMN for registration. The MS selects a PLMN either automatically or manually. In the selected PLMN, the MS searches for a suitable cell and then tunes to the control channel of the selected cell to receive system information. This procedure is called cell selection.

The MS in idle mode always attempts to camp on the best cell according to a signal strength based criterion. After the MS camps on a cell, the received signal strength may deteriorate due to interference or MS mobility. In this case, the MS can select another cell to camp on. This procedure is called cell reselection.

When a cell selection or cell reselection is complete, the MS camps on the selected cell.

After the MS selects a PLMN and finds a suitable cell, the MS must register its current location on the network so that the network knows where to route incoming calls. The MS may move from place to place, and therefore the location changes from time to time. In certain conditions, the MS may initiate a location area update procedure so that the network can locate the MS in real time.

When receiving an incoming call, the network searches for the MS and sends the paging message according to the registered location of the MS.

The idle mode behavior is managed by the MS and is controlled by the parameters contained in the system information that is broadcast on the BCCH.

The idle mode behavior has the following impacts on the network performance and service handling:

Selection of the cell with the best signal strength In the case of cell selection and cell reselection, the MS always attempts to select the cell with the best signal strength to achieve a better QoS. Cell selection and cell reselection are controlled by parameters. By adjusting the settings of these parameters, a cell absorbs MSs in a controlled manner.

Control of the paging load In idle mode, the MS notifies the network of its location whenever the MS changes its location area through the location area update procedure. Then, the network stores the latest location information about the MS. When the network receives an incoming call, it knows in which location area it can page the MS and does not need to page the MS throughout the service area. This reduces the paging load. If the MS does not respond to the first paging message, the network may send a second paging message. The MS, periodically and when switched on or off, notifies the network of its present status through the location area update procedure. This prevents the network from paging the MS when the MS has been switched off or has left the coverage area. Otherwise, this causes unnecessary load to the system.

Low power consumption In idle mode, the MS discontinuously listens to the system information of the serving cell and performs measurements on neighboring cells to evaluate whether a cell change is required. The MS is in sleep mode in most time. Therefore, the power consumption of the MS is low in idle mode.

BSS Idle Mode Behavior 3 Technical Description


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3 Technical Description 3.1 Overview In idle mode, the MS continuously measures the transmit signal strength on the BCCH carrier frequencies of the serving cell and neighboring cells to find a suitable cell to camp on. The MS may also register the location information about the selected cell through a location area update procedure as required.

After camping on a cell, an MS can:

Receive system information from the cell Access the RACH of the cell to initiate a call Receive a paging message from the network when there is an incoming call

The tasks performed by an MS in idle mode can be divided into four procedures. Figure 3-1 illustrates the relations between the four procedures.

1. PLMN selection 2. Cell selection 3. Cell reselection 4. Location area update

Figure 3-1 Relations between the four procedures

PLMN selection

Cell selection

Cell reselection

Location update

User selection of PLMN

Automatic/manual mode selection

Indication to user

PLMNselected

PLMNs available

Initial cell selection

Cell or location area

changes

Service indication

to user

New location

area

Periodic registration

Location update response

3 Technical Description BSS

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3.2 PLMN Selection 3.2.1 Overview The MS will select a PLMN when it is switched on or re-enters the network coverage area. It will attempt to select the last registered PLMN if any exists. When the MS is successfully registered on a PLMN, it shows this PLMN on its screen. The MS is allowed to initiate or receive calls on this PLMN. If there is no last registered PLMN or if the last registered PLMN is unavailable, the MS will attempt to select another PLMN either automatically or manually, depending on its operating mode.

The MS usually operates on its home PLMN. When the MS leaves the coverage area of the home PLMN, it may select another PLMN. If the MS finds a suitable cell to camp on or if a location area update request is accepted, the MS will register on the PLMN. The registration on the PLMN has to be successful in order for the MS to access the network.

In the case of national roaming, the MS may select and register on a visited PLMN. In this case, the MS periodically attempts to return to its home PLMN. The time interval between two consecutive attempts is stored in the subscriber identity module (SIM) and is managed by the network operator.

In the case of international roaming, the MS may select and register on a visited PLMN. In this case, the MS does not attempt to return to its home PLMN.

PLMN selection can be performed in automatic mode or manual mode.

In automatic mode, the MS selects a PLMN from a PLMN list. The PLMNs in the list are ranked in order of priority.

In manual mode, the user selects a PLMN among those indicated by the MS. The user can request the MS to select and register on an available PLMN as required.

3.2.2 Automatic PLMN Selection Mode In automatic mode, the MS selects a PLMN that is available and permitted. If there is no last registered PLMN or the last registered PLMN is unavailable, the MS selects a PLMN in the following order:

1. Home PLMN 2. Each PLMN stored in the SIM, in priority order 3. Other PLMNs with receive level above -85 dBm, in random order 4. All other PLMNs in descending order of signal strength

3.2.3 Manual PLMN Selection Mode In manual mode, if a registered PLMN or the home PLMN exists, the MS first attempts to select the PLMN. If registration fails or the user starts a PLMN reselection, the MS displays all available PLMNs. The user can then select a desired PLMN, which causes the MS to initiate a registration on this PLMN. If the selected PLMN is forbidden, the MS prompts the user to select another PLMN.

3.3 GSM Cell Selection 3.3.1 Overview When an MS is switched on or enters the network coverage area, it scans all the carrier frequencies permitted by the PLMN and selects a suitable cell to camp on. This procedure is called cell selection.



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3.3.2 Conditions for Normally Camping on a Cell To perform services normally, an MS must camp on a suitable cell by registering on the PLMN and tuning to the control channel of the cell. Then, the MS can receive system information and paging messages and initiate calls. A cell is considered suitable when the following conditions are met:

The cell belongs to the selected PLMN. The cell is not barred.

For details about whether a cell is barred, see Table 3-1.

The cell does not belong to a location area included in the list of "forbidden location areas for roaming".

The path loss from the MS to the BTS is lower than the preset threshold, that is, C1 must be greater than 0.

3.3.3 Cell Selection Criterion C1 indicates the path loss criterion of cell selection. C1 of the serving cell must be greater than 0. It is calculated as follows:

C1 = RXLEV - RXLEV_ACCESS_MIN - MAX((MS_TXPWR_MAX_CCH - P), 0)

In the case of a DCS1800 class 3 MS, C1 is calculated as follows:

C1=RXLEV - RXLEV_ACCESS_MIN - MAX((MS_ TXPWR_MAX_CCH + POWER OFFSET - P), 0)

where:

RXLEV indicates the average receive level of the MS in the unit of dBm. RXLEV_ACCESS_MIN indicates the minimum receive level (unit: dBm) required for the MS to access the network. It is specified by the MINUM ACCESS RXLEV parameter.

MS_TXPWR_MAX_CCH indicates the maximum transmit power (unit: dBm) allowed for the MS to access the network. It is specified by the MS_TXPWR_MAX_CCH parameter.

POWER OFFSET indicates Power Deviation (unit: dBm) of the MS. The setting of the Power Deviation Indication parameter determines whether Power Deviation takes effect.

P indicates the maximum output power of the MS in the unit of dBm.

The MS selects a cell to camp on according to the cell selection priority and C1. The selected cell becomes the serving cell. As shown in Figure 3-2, if the two cells have the same cell selection priority, the MS selects Cell1, the one with the higher path loss criterion, as the serving cell.

Figure 3-2 Cell selection

Cell2Cell1

C1=15 C1=8

The cell selection priority is determined by Cell Bar Qualify and Cell Access Bar Switch, as listed in Table 3-1.


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Table 3-1 Cell selection priority

Cell Bar Qualify Cell Access Bar Switch

Cell Selection Priority

Cell Reselection Priority

0 0 Normal Normal

0 1 Forbidden Forbidden

1 0 Low Normal

1 1 Low Normal

3.4 GSM Cell Reselection 3.4.1 Overview After an MS selects a suitable cell as the serving cell, the MS camps on this cell if there are no changes in other conditions. At the same time, the MS continues to monitor all the BCCH carrier frequencies specified in the neighboring cell frequency list (BA1 list), which is indicated by the system information of the serving cell.

For each BCCH carrier frequency, the MS needs to measure the receive level at not less than five sampling points and calculates the average receive level. The total number of sampling points for each BCCH carrier frequency should be the same. In each measurement period, the number of sampling points for each BCCH carrier frequency should also be the same. The six strongest BCCH carrier frequencies need to be updated at least every minute. To save power consumption, the MS needs to measure the receive level of all the carrier frequencies contained in the BA1 list when decoding the messages on the paging subchannel. At the same time, the MS can obtain the BCCH carrier frequencies contained in the BA1 list and some receive level measurement samples of the BCCH carrier frequency of the serving cell.

The MS also performs routine measurements on the BCCH carrier frequency of the serving cell. The MS needs to attempt to decode all the system information that is broadcast on the BCCH of the serving cell at least every 30 seconds. The MS needs to decode the data blocks transmitted over the BCCH carrier frequencies of the six strongest neighboring cells at least every five minutes. The data blocks contain the parameters that affect cell reselection. When the MS finds that a new BCCH carrier frequency becomes one of the six strongest BCCH carrier frequencies, it needs to decode the data blocks transmitted over the new BCCH carrier frequency within 30 seconds. The MS also needs to check the Base Station Identity Code (BSIC) of each of the six strongest neighboring cells at least every 30 seconds to ensure that the same cells are being monitored. If another BSIC is detected, the MS considers that the BCCH carrier frequency is a new one. In this case, the MS decodes the data blocks transmitted over this BCCH carrier frequency. In all the preceding conditions, the MS attempts not to disrupt the monitoring of the PCH.

3.4.2 Conditions for Triggering Cell Reselection Cell reselection is triggered if any of the following conditions is met:

The C2 value of a certain cell (located in the same location area as the serving cell) is greater than the C2 value of the serving cell for five consecutive seconds.

The C2 value of a certain cell (not located in the same location area as the serving cell) is greater than the sum of the C2 value of the serving cell and the value of Cell Reselect Hysteresis Parameters for



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five consecutive seconds. If a cell reselection was performed 15 seconds earlier, a new cell reselection is not triggered.

The serving cell is barred or the serving cell is temporarily barred because of an authentication failure. The MS detects a downlink signaling failure. The occurrence of a downlink signaling failure is controlled by the downlink signaling failure counter. When the MS selects a cell, the counter is initialized to the integer nearest to 90 divided by CCCH Blocks Reserved for AGCH. The counter is increased by one each time the MS successfully decodes a message on its paging subchannel. This counter is decreased by four each time the MS fails to decode a message on its paging subchannel. When the counter becomes zero, it indicates that a downlink signaling failure occurs.

For details about the paging subchannel, see 3.7.2 CCCH Configuration and Paging Group Calculation.

The C1 value of the serving cell is less than 0 for five consecutive seconds. The number of random access attempts exceeds MS MAX Retrans.

3.4.3 Cell Reselection Algorithms When the cell reselection conditions are met, the MS selects one neighboring cell as the serving cell.

Cell reselection adopts the C2 algorithm. C2 is calculated as follows:

If CELL_RESELECT_PENALTY_TIME is not equal to 32, C2 = C1 + CELL_RESELECT_OFFSET – CELL_RESELECT_TEMPORARY_OFFSET x H(CELL_RESELECT_PENALTY_TIME – T)

If CELL_RESELECT_PENALTY_TIME is equal to 32, C2 = C1 - CELL_RESELECT_OFFSET

The function H(x) is defined as follows:

If X > 0, H(x) = 0. If X ≤ 0, H(x) = 1.

The parameters in the formula are described as follows:

CELL_RESELECT_PENALTY_TIME indicates Cell Reselect Penalty Time. In scenarios such as areas along highways, Cell Reselect Penalty Time must be properly set to avoid frequent cell reselections.

T is a timer and its initial value is 0. When a cell is recorded as one of the six strongest neighboring cells, timer T of the cell is started. When the cell is removed from the list of the six strongest neighboring cells, timer T is reset.

CELL_RESELECT_OFFSET indicates Cell Reselect Offset. The C2 value can be manually adjusted by setting Cell Reselect Offset.

CELL_RESELECT_TEMPORARY_OFFSET indicates Cell Reselect Temporary Offset. During the period between the time when timer T is started and the time when the value of timer T reaches Cell Reselect Penalty Time, a negative correction value is applied to C2 based on Cell Reselect Temporary Offset. This prevents a fast moving MS from selecting a micro cell or a small-coverage cell as the serving cell. If Cell Reselect Penalty Time elapses, Cell Reselect Temporary Offset is no longer considered.

The preceding three parameters of the C2 algorithm take effect only when Cell Reselect Parameters Indication is set to YES. Otherwise, the values of these parameters are regarded as zero. Then, C2 is equal to C1.


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The MS selects a cell to camp on according to the cell reselection priority and C2. The selected cell becomes the serving cell. As shown in Figure 3-3, if the two cells have the same cell reselection priority and the reselection hysteresis and the reselection time meet the specified requirements, the MS selects Cell2, the one with greater C2, as the serving cell.

Figure 3-3 Cell reselection

Cell2Cell1

C2=4 C2=18

For details about the cell reselection priority, see Table 3-1.

3.5 Location Area Update 3.5.1 Overview When an MS moves from one location area to another, it must register the new location information on the network. That is, when the MS finds that the LAI stored in the SIM is different from the LAI of the serving cell, it must notify the network to update the stored location area information about the MS. This procedure is called location area update.

An LAI consists of mobile country code (MCC), mobile network code (MNC), and location area code (LAC).

MCC is specified by the MCC parameter. MNC is specified by the MNC parameter. LAC is specified by the Cell LAC parameter.

If cell reselection occurs when an MS in idle mode moves in the same location area, the MS does not notify the network of the cell change. If the two cells before and after cell reselection belong to different location areas, the MS needs to notify the network of the cell change, and this is called "forced registration" in mobile communication.

According to the identifier of location area update, location area updates are classified into three types: normal location area update, IMSI attach/detach, and periodic location area update.

The location area update procedures for normal location area update, periodic location area update, and IMSI attach are basically the same, as shown in Figure 3-4.



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Figure 3-4 Location area update

MS BTS MSCBSC

RACH

Immediate Assignment Procedure

ChannelRequest(1)

Establish Indication(Location Update Request)(2) CR(Complete

Layer3 Information)

CC(3)LocationUpdationg Accepted(4)

SDCCH

SDCCH

LocationUpdationg Rejected(5)

SDCCH

TMSIReallocation Complete(6)

Clear Command(7)

Clear Complete(7)

In an immediate assignment procedure, the MS sends the BTS a Channel Request message through the RACH, indicating the access cause "location update".

1. When the MS initiates a location area update request, an immediate assignment procedure is started. The BTS sends the BSC an Establish Indication message, which contains the content of the Location Updating Request message.

2. The BSC establishes an SCCP link over the A interface. Then, the BSC sends the MSC a Complete Layer3 Information message, which contains the cell global identity (CGI) of the current cell.

3. The MSC responds to the BSC with a Connection Confirm message. 4. The MSC sends the MS a Location Updating Accepted message, indicating that the location area

update is successful. 5. If the network rejects the location area update request, it sends a Location Updating Rejected

message to the MS. 6. If the TMSI allocation in the case of location area update is enabled on the MSC side, a TMSI

Reallocation Complete message is sent to the MSC in the location area update procedure. 7. The MSC sends the BSC a Clear Command message to start the resource release procedure on

the network side.

3.5.2 Location Area To determine the location of an MS, the coverage area of each GSM PLMN is divided into multiple location areas. Each location area contains one or more cells. The network stores the location area information about each MS for paging. After receiving an incoming call, the network pages the MS in the corresponding location area instead of in all the cells controlled by the MSC. Each location area is


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identified by a location area identity (LAI), which is broadcast through the system information over the BCH.

The sizes of location areas are key factors that determine the system performance. Location areas have to be properly divided during network planning.

If the size of a location area is too small, more location area updates will take place. This increases the signaling load.

If the size of a location area is too large, a paging message will be sent in all the cells under the location area when the network pages an MS. This increases the load on the PCH and the signaling load on the Abis interface.

Therefore, the planning of location areas is an important task. During division of location areas, ensure that location area updates are reduced to a smallest possible number without causing heavy paging load. This is to prevent a wastage of network resources.

3.5.3 Normal Location Area Update When an MS moves from one location area to another, it initiates a normal location area update. A normal location area update is used to update the location information registered on the network by the MS. The Location Update Type information element in the Location Update Request message should indicate that it is a normal location area update.

3.5.4 IMSI Attach/Detach The IMSI attach/detach procedure informs the MSC/VLR whether the MS can be reached.

The Attach-detach Allowed parameter controls whether the network needs to be notified of IMSI attach/detach.

If Attach-detach Allowed is set to YES, the MS sends a Location Updating Request (IMSI Attach) message to the network when it is switched on, indicating that the MS is active. After receiving the message, the network updates the state of the MS so that the network can page the MS as required.

If Attach-detach Allowed is set to YES, the MS sends an IMSI Detach message to the network when it is switched off, indicating that the MS is inactive. After receiving this message, the network will not send paging messages to the MS, thus saving network resources.

3.5.5 Periodic Location Area Update When any of the following conditions occurs, the MS loses contact with the network. If the MS is paged in this case, the network sends a paging message to the location area registered by the MS. The paging expires definitely and the system resource is used ineffectively.

When the MS is switched on and moves into a blind area, the network cannot know the current state of the MS but still considers that the MS is attached.

When the MS sends an IMSI Detach message to the network, the network may not correctly decode the message due to poor uplink quality. As a result, the network still considers that the MS is attached.

When the MS is down accidentally, it loses contact with the network.

To solve these problems, the GSM system implements a certain mechanism, which instructs the MS to automatically report its location information to the network at regular intervals. The mechanism is called periodic location area update. By adopting this mechanism, the network can know in time whether the status of the MS has changed.

Periodic location area update is used to periodically notify the network of the MS availability. When the MS sends a Location Update Request message to the network, the Location Update Type information element in the message indicates that it is a periodic location update.



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The network sends the periodic location update timer value to all the MSs in the cell through the system information over the BCCH. The value is specified by T3212. When this timer expires, the MS automatically sends a location area update request to the network. After the MS performs a cell selection or reselection, it reads T3212 from the system information of the serving cell, starts this timer, and stores the timer on the SIM. When the MS detects that T3212 expires, it automatically sends a location area update request to the network.

The signaling procedure of a periodic location area update is the same as the signaling procedure of a normal location area update.

3.6 Control Channels The control channels for the MS in idle mode include broadcast channels and Common Control Channels (CCCHs).

The Dedicated Control Channels (DCCHs) are used for the MS in dedicated mode and are not described in this document.

Broadcast Channels Broadcast channels, including Frequency Correction Channel (FCCH), Synchronization Channel (SCH), Broadcast Control Channel (BCCH), and Cell Broadcast Channel (CBCH), are all downlink channels used for sending broadcast messages to the MS.

FCCH The network sends frequency correction signals over the FCCH to the MS. The FCCH enables the MS to synchronize its frequency (with a specified frequency).

SCH The network sends the frame synchronization number and base station identity code over the SCH to the MS.

BCCH The network sends the common messages related to all its cells over the BCCH to the MS.

CBCH The network broadcasts services over the CBCH within a cell. The physical channels used by the CBCH are the same as those used by the SDCCH.

CCCHs The CCCHs include Paging Channel (PCH), Random Access Channel (RACH), Access Grant Channel (AGCH), and Notification Channel (NCH).

PCH The PCH is a downlink channel. The MS monitors the PCH at certain intervals to determine whether it can receive a call from the MSC.

RACH The RACH is an uplink channel. The MS accesses the network through the RACH and requests the network to assign an SDCCH.

AGCH The AGCH is a downlink channel. The network notifies the MS of the assigned dedicated channel (SDCCH or TCH) through the AGCH.

NCH


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The NCH is a downlink channel, which is used to notify the MS of Voice Group Call Service (VGCS) and Voice Broadcast Service (VBS) calls.

3.7 Paging 3.7.1 Overview Through the paging process, an MS is instructed to access the network to complete call connection. Different paging algorithms have different paging efficiencies. Huawei GBSS paging algorithm has the following benefits:

Paging capability is one of the criteria that measure the system performance. Huawei GBSS paging algorithm maximizes the paging capability of the system, while maintaining paging efficiency and minimizing paging load.

Through reliable paging, Huawei GBSS paging algorithm enables MSs to receive every possible call. This reduces customer complaints and improves customer satisfaction.

3.7.2 CCCH Configuration and Paging Group Calculation In the GSM system, the MS reads the information on the CCCH of the serving cell at least once in every 30s. In the downlink, the CCCHs include AGCH and PCH. One CCCH can be carried on one or more physical channels. In the case of high paging traffic in a location area, one physical timeslot for paging message transmission is insufficient. The GSM protocol allows multiple CCCHs to be configured on one TRX carrying the BCCH. The CCCHs can be configured only on timeslot 0, 2, 4, or 6.

The number of CCCH message blocks in a cell reflects the resources that can be used by the AGCH or the PCH in the cell. Table 3-2 lists the mapping between the CCCH configuration and the number of CCCH message blocks in a BCCH multiframe.

Table 3-2 Mapping between the CCCH configuration and the number of CCCH message blocks in a BCCH multiframe

CCCH Configuration Number of CCCH Message Blocks in a BCCH Multiframe

The CCCH uses one physical channel exclusively. It does not share this physical channel with the SDCCH.

9

The CCCH uses one physical channel. It shares this physical channel with the SDCCH.

3

The CCCH uses two physical channels exclusively. It does not share these physical channels with the SDCCH.

18

The CCCH uses three physical channels exclusively. It does not share these physical channels with the SDCCH.

27



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Number of CCCH Message Blocks in a CCCH Configuration BCCH Multiframe

The CCCH uses four physical channels exclusively. It does not share these physical channels with the SDCCH.

36

In different CCCH configurations, each BCCH multi-frame (containing 51 frames) includes different numbers of CCCH message blocks. The CCCH is shared by the AGCH and the PCH. When messages need to be transmitted on both the PCH and the AGCH, the network prefers the PCH. To prevent the occurrence of message congestion on the AGCH when the traffic on the PCH is high, the network reserves a certain number of message blocks for the AGCH. The CCCH BLOCKS RESERVED FOR AGCH parameter specifies the number of message blocks reserved for messages on the AGCH of the CCCH in a BCCH multi-frame.

Each MS (corresponding to an IMSI) belongs to a paging group. Each paging group corresponds to a paging subchannel in a cell. The MS determines its paging group based on its IMSI, and then determines the location of the paging subchannel of its paging group. In the actual network, the MS listens to only its paging subchannel but ignores other paging subchannels. When other paging subchannels are used, part of the MS is even powered off to save power overhead (which is the power supply to the DRX). The MULTI-FRAMES IN A CYCLE ON THE PAGING CH parameter specifies the number of BCCH multi-frames that form a cycle for the paging subchannels. This parameter determines the number of paging subchannels into which paging channels in a cell are divided.

The formula for calculating the number of paging groups is:

When the CCCH and the SDCCH share one physical channel, the number of paging groups = (3 - CCCH BLOCKS RESERVED FOR AGCH) x BS_PA_MFRAMS.

When the CCCH and the SDCCH do not share one physical channel, the number of paging groups = (9 - CCCH BLOCKS RESERVED FOR AGCH) x BS_PA_MFRAMS.

The formula for calculating the paging group mapped to the MS is:

Paging group number = ((IMSI mod 1000) mod (Number of cell paging groups)) div MULTI-FRAMES IN A CYCLE ON THE PAGING CH

For PS services, if the parameter Support SPLIT_PG_CYCLE on CCCH is enabled, the formula for calculating paging groups may be different.

The MS determines the mapped paging group based on the IMSI and the configuration of paging channels in the serving cell, and then determines the paging subchannel of the mapped paging group.

3.7.3 CS Paging CS paging messages are transmitted on the PCH. When a call reaches the MSC of the called MS, the MSC determines the area where the MS is located and broadcasts paging messages to all the BSCs in this area. Based on the location area, the BSC determines the cells to which paging messages are sent and performs IMSI-based calculation of the paging group mapped to the MS.

The MS in idle mode listens to its paging subchannels. If the IMSI or TMSI contained in the Paging Request message is consistent with its own IMSI or TMSI, the MS sends a Channel Request message to trigger an initial channel assignment procedure, and sends a Paging Response on the assigned channel.


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The MSC determines whether to use TMSI-based or IMSI-based paging.

If IMSI-based paging is used, the paging message contains the IMSI only. If TMSI-based paging is used, the paging message contains both TMSI and IMSI. The IMSI is used by the BSC to

calculate paging groups.

3.7.4 PS Paging The PS paging procedure is similar to the CS paging procedure. During the PS paging procedure, the function of the SGSN is similar to that of the MSC. The paging strategy of the SGSN determines whether the P-TMSI or IMSI is used for paging. The SGSN initiates PS paging when transmitting downlink data to an MS. PS paging messages are carried on the PS paging channels (if configured) or on the PCHs if the PS paging channels are not configured.

Only the MS in the STANDBY state can be paged. The SGSN obtains the Routing Area of the MS and sends a paging message to the entire Routing Area.

The location information of the MS in the STANDBY state contains only the Routing Area information of the GPRS.

3.7.5 Paging Modes Huawei GBSS supports the following standard paging modes:

Common paging mode The MS calculates the mapped paging group based on the IMSI and the configuration of paging channels in the serving cell, and then calculates the paging subchannel of the mapped paging group. Paging messages are sent on only this paging subchannel.

Complete paging mode When an MS group is informed that it is in complete paging mode, paging messages of this group may be sent on any PCH of the same timeslot. When the PCH configuration dynamically changes, paging message loss can be avoided.

Spaced paging mode The BSS adds the paging messages of a group to another paging channel to avoid temporary overload. That is, the MS can receive paging messages on paging channel N+2 in spaced paging mode, whereas it receives paging messages on paging channel N in common paging mode.

3.7.6 Paging Functions Huawei GBSS supports the paging queue, paging retransmission, paging combination, and paging flow control functions. These functions can effectively improve and guarantee the paging capacity of the BSC.

Paging queue The transmission of paging messages on the Um interface is limited by paging groups. The paging messages of a paging group can be transmitted only on the message blocks to which the paging group is mapped. The BTS implements the paging queue function to wait for opportunities for transmission by temporarily buffering the paging messages received from the BSC. The BTS selects a paging message and transmits it on the corresponding message block whenever an opportunity comes. Paging messages of the same priority follow the rule of "first come, first served (FCFS)". To guarantee the scheduling efficiency for paging messages on the Um interface, the BTS Paging Lifetime parameter specifies the life cycle of a paging queue in the BTS. The setting of this parameter must be consistent with the setting of the paging timer T3113 of the core network. It is recommended that the BTS Paging Lifetime parameter be set to a value that is 1s to 2s shorter than T3113.



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Paging retransmission As the message on the downlink CCCH is transferred in unacknowledged mode on the LAPDm layer of the Um interface, there is a risk of message loss. Paging retransmission is used to reduce this risk. Generally, the MSC and BSS provide two levels of retransmission. One level is at the MSC, where paging messages are retransmitted in a long period to handle long interruptions. The other level is at the BTS, where paging messages are retransmitted in a short time and traffic flow on the Abis and A interfaces can be reduced. Huawei BSS supports the paging retransmission function. When the message block has neither paging messages nor immediate assignment messages to be transmitted, the paging messages that have been transmitted on this message block will be retransmitted. The maximum number of paging retransmissions of the same message is specified by the Paging Times parameter. Paging messages on the MSC side are retransmitted at a fixed interval and the paging retransmission is controlled by the parameters on the MSC side. The paging retransmission on the BTS side is implemented by the Paging Times parameter. Paging messages on the BTS side are not retransmitted at a fixed interval but scheduled in the paging queues for retransmission. The paging queues for retransmission have lower priority than normal paging queues. Maximum number of paging message transmissions on the Um interface = Number of pagings configured on the MSC side x Paging Times configured on the BTS side.

Paging combination Paging combination is used to improve the utilization of the Um interface. The Paging Command message sent from the BSC to the BTS contains the information of an MS. The BTS tries to combine all the Paging Command messages of the MSs belonging to the same paging group, and sends with the Paging Request messages to the MSs. One Paging Request message contains the TMSIs or IMSIs of multiple MSs. One TMSI consists of 3 digits, and one IMSI consists of 15 digits. The length of the Paging Request message is limited. The combination capability depends on whether the combined paging commands use the IMSI-based or TMSI-based paging. The MS determines whether to respond to the paging request by resolving the Mobile Identity field (including the TMSI or IMSI) in the Paging Request message. The protocols specify three paging request types. Their combination modes are as follows: − Paging request type 1

One Paging Request message combines one to two Paging Command messages. − IMSI − IMSI+IMSI − IMSI+TMSI/P − TMSI/P − TMSI/P+TMSI/P − Paging request type 2

One Paging Request message combines two to three Paging Command messages. − TMSI/P+TMSI/P − TMSI/P+TMSI/P+IMSI − TMSI/P+TMSI/P+TMSI/P − Paging request type 3

One Paging Request message combines four Paging Command messages. − TMSI/P+TMSI/P+TMSI/P+TMSI/P The efficiency of paging combination depends on whether TMSI-based or IMSI-based paging is used.

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When the paging flow sent by the MSC exceeds the processing capability of the BSS, the BSS controls the flow according to the current network status. The paging flow control function ensures the robustness and normal working of the BSS, the high capability of the BSS to process paging messages, and the smoothness and stability of services. For details about paging flow control, see the Flow Control Feature Parameter Description.

3.8 System Information 3.8.1 Overview System information involves main radio network parameters on the Um interface, including network identity parameters, cell selection parameters, system control parameters, and network function parameters. Based on the received system information, an MS can properly select and access a radio network. Then, it can gain access to all types of service provided by the network.

System information is classified into the following types:

Broadcast system information For an MS in idle mode, the network provides broadcast system information, indicating the location of the MS and the types of service the MS can obtain. Some parameters involved in the broadcast system information control cell reselection of the MS.

Dedicated system information For an MS in dedicated mode, the network provides dedicated system information, part of which controls transmission, power, and handover of the MS.

Broadcast system information and dedicated system information are closely associated. The contents of broadcast system information can be the same as those of dedicated system information, whereas the contents of dedicated system information can be different from those of broadcast system information. The reason is that dedicated system information is intended for one MS, but broadcast system information is intended for all MSs in idle mode in a certain cell.

BSS system information consists of System Information Types 1, 2, 2BIS, 2TER, 2QUATER, 3, 4, 5, 5BIS, 5TER, 6, 7, 8, 10, and 13.

System Information Types 5, 5BIS, 5TER, and 6 are used for only the MSs in dedicated mode. System Information Type 13 contains parameters related to GPRS services. When the cell supports GPRS services, System Information Type 13 is sent on the BCCH.

3.8.2 System Information Type 1 Functions System Information Type 1 is sent on the BCCH to provide information about control of the RACH and of the cell allocation (CA).

Contents Table 3-3 lists the contents of System Information Type 1.

Table 3-3 Contents of System Information Type 1

Type Content

Cell Channel Desc SYS INFO 1

RACH Control Para



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Type Content

SI 1 Rest Octets

The contents of System Information Type 1 are described as follows:

CA list One cell can be configured with a maximum of 64 frequencies. The actual configuration of cell frequencies is subject to the Cell Channel Description, as listed in Table 3-4. The BSC selects a format of cell channel description based on the actual configuration of cell frequencies. The format of cell channel description is defined by octet 2, Format ID (Bit 128, Bit 127, Bit 124, Bit 123, and Bit 122), as listed in Table 3-5.

Table 3-4 Format of cell channel description

8 7 6 5 4 3 2 1

Cell Channel Description IEI octet 1

Bit Bit 0 0 Bit Bit Bit Bit

128 127 Spare Spare 124 123 122 121

octet 2

Bit Bit Bit Bit Bit Bit Bit Bit

120 119 118 117 116 115 114 113 octet 3

… … … … … … … … …

Bit Bit Bit Bit Bit Bit Bit Bit

8 7 6 5 4 3 2 1 octet 17

Table 3-5 Format of cell channel description

Bit128 Bit127 Bit124 Bit123 Bit122 Format Notation

0 0 X X X bit map 0

1 0 0 X X 1024 range

1 0 1 0 0 512 range

1 0 1 0 1 256 range

1 0 1 1 0 128 range

1 0 1 1 1 variable bit map

Different formats of cell channel description correspond to different numbers of available cell frequencies. Assume that the number of available frequencies for a cell is n (except for duplicate and


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invalid frequencies) and ARFCN(i) (i=1,…,n) represents the Absolute Radio Frequency Channel Number. Then, the numbers of available frequencies for different formats of cell channel description are as follows: − Bit map 0

The bit map 0 format is used for GSM900 frequencies. The number of available frequencies is 64 if 1 ≤ ARFCN(i) ≤ 124.

− 1024 range If the 1024 range format is used, the number of available frequencies for a cell is equal to or smaller than 16. For a GSM900 cell, 1 ≤ ARFCN(i) ≤ 124. For a GSM1800 cell, 512 ≤ ARFCN(i) ≤ 885.

− 512 range If the 512 range format is used, the number of available frequencies for a cell is equal to or smaller than 18. The interval between any two ARFCNs must be less than 512.

− 256 range If the 256 range format is used, the number of available frequencies for a cell is equal to or smaller than 22. The interval between any two ARFCNs must be less than 256. For example, in the 256 range format, ARFCNs 512 and 812 cannot be configured simultaneously.

− 128 range If the 128 range format is used, the number of available frequencies for a cell is equal to or smaller than 29. The interval between any two ARFCNs must be less than 128. For example, in the 128 range format, ARFCNs 512 and 712 cannot be configured simultaneously.

− Variable bit map If the variable bit map format is used, the number of available frequencies for a cell is equal to or smaller than 64. The interval between any two ARFCNs must range from 1 to 111. For example, in the variable bit map format, it is allowed to configure 64 frequencies with the ARFCNs 512 to 575 with an increment of 1, but it is not allowed to configure 64 frequencies with the ARFCNs 512 to 638 with an increment of 2.

The previously mentioned restrictions are mainly applied to GSM1800 frequencies.

RACH Control Para The RACH Control Para information element contains the following parameters: − MS MAX Retrans − TX-integer − Cell Access Bar Switch − Common Access Control Class and Special Access Control Class

The access control class is categorized into classes 0-9 and 11-15. Generally, each GSM MS has an access class, represented by a bit. If this bit is set to 1, MSs of the corresponding class are barred from accessing the current cell. Otherwise, they are allowed to access the cell.

− Call Reestablishment Forbidden − Emergent Call Disable

The time interval between two consecutive Channel Request messages sent by an MS is indicated by a random value from {S, S+1,....S+T-1}. The unit of the time interval is TDMA frame. Here, S is subject to the common control channel configuration, which is delivered in System Information Type 3; T is TX-integer. Table 3-6 lists the relation between S and T.



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Table 3-6 Relation between S and T

TX-integer Non Combined CCCH Combined CCCH

3, 8, 14, 50 55 41

4, 9, 16 76 52

5, 10, 20 109 58

6, 11, 25 163 86

7, 12, 32 217 115

If satellite transmission is used, it is recommended that MS MAX Retrans be set to 4 and TX-integer be set to 32 to reduce the delay caused by satellite transmission.

SI 1 Rest Octets The SI 1 Rest Octets information element has eight bits. It contains spare bits and indication of the PCS1900 and DCS1800.

3.8.3 System Information Types 2, 2BIS, 2TER, and 2QUATER Functions The functions of System Information Types 2, 2BIS, 2TER, and 2QUATER are as follows:

System Information Type 2 is sent on the BCCH to provide information about the RACH control, the NCC Permitted, and the BCCH allocation list (BA1 list) in neighboring cells. − Generally, System Information Types 2, 2BIS, and 2TER describe different parts of the BA1 list. The

MS reads and decodes the BA1 list and then performs cell reselection in idle mode. − A phase 1 MS in GSM900 recognizes only the neighboring cell frequencies described in System

Information Type 2 and ignores those described in System Information Types 2BIS and 2TER. System Information Type 2BIS is sent on the BCCH to provide information about the RACH control and the extension of the BCCH allocation list in the neighboring cells (part of the BA1 list). System Information Type 2BIS is optional. Generally, System Information Type 2 carries the information about a limited number of frequencies that are included in the BA1 list. In this situation, System Information Type 2BIS carries the information about other frequencies that are included in the BA1 list and are on the same frequency band as the frequencies carried by System Information Type 2.

System Information Type 2TER is sent on the BCCH to provide information about the extension of BCCH allocation list in neighboring cells (part of the BA1 list). System Information Type 2TER carries the information about the frequencies that are on different bands from the frequencies of the current cell. Only the dual-band MSs read System Information Type 2TER. The GSM900 MSs and the GSM1800 MSs ignore this message.

System Information Type 2QUATER provides information about the BCCH allocation in neighboring 3G cells. It is used for the reselection of 3G cells. System Information Type 2QUATER is sent when inter-RAT handover is required and neighboring 3G cells are configured.

In a dual-band network, the Send System Information 2ter parameter specifies whether to send System Information Type 2TER. In a non-dual-band network, the SI 2ter Switch parameter specifies whether to send System Information Type 2TER.

The Support Sent 2QUATER parameter specifies whether to send System Information Type 2QUATER.


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Contents Table 3-7 lists the contents of System Information Types 2, 2BIS, 2TER, and 2QUATER.

Table 3-7 Contents of System Information Types 2, 2BIS, 2TER, and 2QUATER

Type Content

Neighbor Cell Desc

NCC permitted

SYS INFO 2

RACH Control Para

Neighbor Cell Desc SYS INFO 2 BIS

RACH Control Para

SYS INFO 2TER Neighbor Cell Desc. (Extended)

SYS INFO 2QUATER SI 2quater Rest Octets

The contents of System Information Types 2, 2BIS, 2TER, and 2QUATER are described as follows:

Neighbor Cell Desc (BA1 list) The Neighbor Cell Description information element provides the ARFCNs of the BCCH carriers in the neighboring cells of the current cell. Currently, Huawei BSS supports a maximum of 32 neighboring cells per cell. Except for bit 5 (BA-IND) and bit 6 (EXT-IND) of octet 2, the Neighbor Cell Description information element is coded in the same way as the Cell Channel Description information element. For details, see the cell channel description in 3.8.2 System Information Type 1. − The extension indication (EXT_IND) is sent in System Information Types 2 and 5. It indicates

whether extended neighboring cell frequencies are sent in System Information Types 2BIS and 5BIS. It has one bit. If the EXT_IND bit is set to 0, System Information Types 2 and 5 carry the complete BA list. If the EXT_IND bit is set to 1, System Information Types 2 and 5 carry only part of the BA list. − The BA indication (BA_IND) is sent in System Information Types 2 and 5. It has one bit and is used

by the MS to discriminate changes in the BA1 or BA2 list. In other words, if the neighboring cell relation and the BA2 list are modified during the conversation, the BA_IND bit in System Information Type 5 should be 1, indicating that the MS needs to decode the neighboring cell frequencies again. NCC Permitted The NCC Permitted parameter is sent in System Information Types 2 and 6. It has eight bits and provides all the NCCs required by MSs. In other words, if bit N is 0 (0 ≤ N ≤ 7), the MS does not measure the power level of the cell where the NCC is N, indicating that the MS is not reselected or handed over to the network where the NCC is N. This parameter is mainly used for handover and cell reselection.

RACH Control Para For details about the RACH Control Para information element, see 3.8.2 System Information Type 1.

Neighbor Cell Desc. (Extended) The Neighbor Cell Desc. (Extended) information element is sent in System Information Types 2TER and 5TER. Except for bit 5 (BA-IND) and bits 6 and 7 (Multi-band report) of octet 2, this information element is coded in the same way as the Cell Channel Description information element. For details, see 3.8.2 System Information Type 1.

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The Multi-band report parameter is sent in System Information Types 2TER and 5TER. It has two bits and is used to request the dual-band MS to report information about neighboring cells of multiple bands. For details, see Table 3-8.

Table 3-8 Multiband reporting

Multiband Reporting (Two Bits)

Meaning

0 The MS reports the measurement results of the top six neighboring cells where the signal strength is the strongest, irrespective of the band used.

1 If there is a neighboring cell that is on a different band from the serving cell and if the MS is allowed to camp on the neighboring cell, the MS reports the measurement results of the neighboring cell. At the other five positions, it reports the measurement results of the neighboring cells that are on the same band as the serving cell.

10 If there are two neighboring cells that are on a different band from the serving cell and if the MS is allowed to camp on the neighboring cells, the MS reports the measurement results of the two neighboring cells. At the other four positions, it reports the measurement results of the neighboring cells that are on the same band as the serving cell.

11 If there are three neighboring cells that are on a different band from the serving cell and if the MS is allowed to camp on the neighboring cells, the MS reports the measurement results of the three neighboring cells. At the other three positions, it reports the measurement results of the neighboring cells that are on the same band as the serving cell.

SI 2quater Rest Octets The SI 2quater Rest Octets information element contains the following parameters: − BA_IND − 3G_BA_IND − MP_CHANGE_MARK − 3G Neighbour Cell Description − Index_Start_3G − UTRAN FDD DESCRIPTION − UTRAN TDD DESCRIPTION − 3G MEASUREMENT PARAMETERS Description

These parameters belong to the parameters related to external 3G cells.


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3.8.4 System Information Type 3 Functions System Information Type 3 is sent on the BCCH to provide information about the location area identification, cell identity, RACH control, and parameters related to cell selection. The information is mandatory.



Type Content

Cell Identity

LAI

Cell Option (BCCH)

Cell Selection Para

RACH Control Para

SYS INFO 3

SI 3 Rest Octets


CGI The Cell Global Identity (CGI) consists of the Location Area Identity (LAI) and the Cell CI. The LAI consists of the MCC, MNC, and Cell LAC. System Information Types 3, 4, and 6 contain all or part of the CGI. Upon receiving the system information, the MS decodes the CGI. Based on the MCC and the MNC, the MS determines whether to access the network through this cell and whether the current location area has changed. If the location area has changed, the MS initiates a location area update procedure.

Control Channel Desc The Control Channel Desc information element contains the following parameters: − MSC Version Indication

The MSC Version Indication parameter indicates when the MSC was released. This parameter has one bit. If the bit is set to 0, the MSC was released in 1998 or earlier. If the bit is set to 1, the MSC was released in 1999 or later.

− Attach-detach Allowed − CCCH-CONF

The CCCH-CONF parameter determines the combination mode of the CCCH. The CCCH-CONF has three bits. Table 3-10 describes the meaning of the CCCH-CONF.



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Table 3-10 Meaning of the CCCH-CONF

CCCH-CONF (Three Bits)

Number of CCCH Message Blocks in One BCCH Multiframe

Meaning

000 9 One physical channel used for CCCH, not shared with SDCCHs

001 3 One physical channel used for CCCH, shared with SDCCHs

010 18 Two physical channels used for CCCH, not shared with SDCCHs

100 27 Three physical channels used for CCCH, not shared with SDCCHs

110 36 Four physical channels used for CCCH, not shared with SDCCHs

Others - Reserved

− CCCH Blocks Reserved for AGCH − Multi-Frames in a Cycle on the Paging CH − T3212

Cell Option (BCCH) The Cell Option (BCCH) information element contains the following parameters: − PWRC − FR Uplink DTX − Radio Link Timeout

Cell Selection Para The Cell Selection Para information element affects the behaviors of an MS after the MS is switched on. It contains the following parameters: − Cell Reselect Hysteresis Parameters − MS_TXPWR_MAX_CCH − MINUM ACCESS RXLEV − Additional Reselect Parameter Indication

The Additional Reselect Parameter Indication indicates whether the MS uses C2 during cell reselection. It has one bit. In System Information Type 3, this parameter is meaningless. In System Information Type 4, value 0 of the bit indicates that the SI4 Rest Oct of System Information Type 4 is used to calculate the parameters related to C2; value 1 indicates that the SI4 Rest Oct of System Information Types 7 and 8 are used to calculate the parameters related to C2.

− Support Half Rate RACH Control Para For details, see 3.8.2 System Information Type 1.

SI 3 Rest Octets The SI 3 Rest Octets information element contains the following parameters:


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− Cell Reselect Parameters Indication − Cell Bar Qualify − Cell Reselect Offset − Cell Reselect Temporary Offset − Cell Reselect Penalty Time − Send System Information 2ter − ECSC − Support GPRS − Support Sent 2QUATER

3.8.5 System Information Type 4 Functions System Information Type 4 is sent on the BCCH to provide information about the location area identification, RACH control, cell selection parameters, and CBCH.

Information about the location area identification, RACH control, cell selection parameters is mandatory.

Information about CBCH is optional. It contains the configurations of the CBCH and the related frequency information. It is used when the system supports cell broadcast.



Type Content

LAI

Cell Selection Para

RACH Control Para

CBCH Channel Desc. (option)

CBCH Mobile Allocation (option)

SYS INFO 4

SI 4 Rest Octets


Location Area Identification (LAI) For details, see 3.8.4 System Information Type 3.

Cell Selection Para. For details, see 3.8.4 System Information Type 3.

RACH Control Para. For details, see 3.8.2 System Information Type 1.

CBCH Channel Description and CBCH Mobile Allocation (CBCH MA)



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Both CBCH Channel Description and CBCH MA are optional. If the system supports cell broadcast, CBCH Channel Description indicates the configuration of the CBCH. If the CBCH is in frequency hopping mode, CBCH MA is mandatory.

SI 4 Rest Octets If the cell selection parameter Additional Reselect Parameter Indication is set to No, the SI 4 Rest Octets is used to calculate the value of the cell reselection parameter C2. The SI 4 Rest Octets information element contains the following parameters: − Cell Reselect Parameters Indication − Cell Bar Qualify − Cell Reselect Offset − Cell Reselect Temporary Offset − Cell Reselect Penalty Time

3.8.6 System Information Type 7 Functions System Information Type 7 is sent on the BCCH to provide information about cell reselection.



Type Content

SYS INFO 7 SI 7 Rest Octets


SI 7 Rest Octets contains the cell selection and reselection parameters used by the MS. It may also contain the Power Deviation parameter used by the DCS1800 Class 3 MS.

The coding scheme of SI 7 Rest Octets is the same as that of SI 4 Rest Octets. For details, see 3.8.5 System Information Type 4.

3.8.7 System Information Type 8 This section describes the functions and contents of System Information Type 8.

Functions System Information Type 8 is mandatory and is sent on the BCCH. It provides information about cell reselection.



Type Content



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SI 8 Rest Octets contains the cell reselection parameters used by the MS. It may also contain the Power Deviation parameter used by the DCS1800 Class 3 MS.

The coding scheme of SI 8 Rest Octets is the same as that of SI 4 Rest Octets. For details, see 3.8.5 System Information Type 4.

3.8.8 System Information Type 13 Functions System Information Type 13 provides information about the parameters related to GPRS services. It is sent on the BCCH when GPRS services are supported.



Type Content


The SI 13 Rest Octets information element contains the following parameters:

RAC RAC contains Routing Area and Routing Area Color Code.

Support SPLIT_PG_CYCLE on CCCH Packet Access Priority Network Control Mode PSI1 Repetition Period

In addition, System Information Type 13 also contains parameters such as GPRS Mobile Allocation, GPRS Cell Options, GPRS Power Control Parameters struct, and PBCCH Description struct.

3.9 Short Message Service Cell Broadcast The short message service cell broadcast (SMSCB) is a teleservice (TS23) that periodically broadcasts messages to all the MSs in a specified area. Based on different settings, the MS can continuously or discontinuously receive short messages, such as weather forecast and traffic information.

The SMSCB allows all the MSs in a specified area to receive short messages. The area may cover one or more cells, or even the entire PLMN. The Cell Broadcast Database (CDB) of the BSC manages and schedules the short messages from the cell broadcast center (CBC). Then, the BSC sends the short messages to the BTS. After that, the BTS broadcasts the messages to all the MSs in a specified area at certain intervals.

The CDB receives and stores the short messages, schedules and sends the messages according to a certain algorithm, and responds to the query from the CBC.

The MS can receive the messages in DRX mode. That is, the MS can work discontinuously. Through a scheduling message, the BSC notifies the MS that no short message is sent during a particular period.



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Therefore, the MS needs to receive short messages only in the specified period, thus reducing the power consumption.

The SMSCB supports the BTS flow control. That is, the order in which the short messages are sent is scheduled by the CDB, but the messages are actually sent by the BTS. Each TRX of the BTS maintains one message buffer and periodically sends cell broadcast short messages on a specified channel. When the messages are not sent in time, the BTS reports the out-of-synchronization situation to the BSC through a LOAD IND message. By controlling the BTS flow, the CDB maintains the balance of the cell broadcast system, thus meeting the requirements for sending messages.

Huawei BSS also supports simplified cell broadcast. Without a CBC, Huawei simplified cell broadcast feature supports the most commonly used standard cell broadcast services with low equipment costs and low OM costs, thus reducing the operator's CAPEX.

For details about the SMSCB, see Cell Broadcast Feature Parameter Description.

3.10 Public Voice Group Call Service 3.10.1 Overview The public voice group call service (VGCS) simultaneously provides voice services for a group of MSs in a pre-defined area in half-duplex mode. This area is called the group call area.

The network side defines the group call number, group members, and coverage area. The MS who has the permission can dial the group call number to originate a group call. All the group members within the coverage area can be informed to join the group call. During the group call, every relevant cell has a group call channel, in which only the current speaker uses the uplink (group transmission mode) and all the listeners wait in the downlink (group reception mode). One of the group members can press and hold the PTT key on the mobile phone to speak to others. During this period, other members can only listen but cannot talk by pressing PTT. Other group members can speak by pressing PTT only after the speaker releases PTT. When the conversation is complete, the group call originator terminates the call by pressing the on-hook key and then all the group members hang up.

In addition, the VGCS provides dispatcher service. The dispatcher is a special user of the fixed network or the mobile network defined by the network side. The dispatcher has the permission to talk at any time during a group call and originates or terminates a group call authorized by the network side.

A VGCS channel is similar to a TCH. When a VGCS or VBS call is established, each cell in the group call area is assigned an A-interface circuit and a radio channel. In the group call area, the listening subscribers of the same VGCS call share the downlink of the channel. The VGCS subscribers preempt the uplink of the channel at different time points. This channel is called the group call channel.

3.10.2 System Information The system information related to a group call is classified into System Information Types 1, 6, and 10.

System Information Type 1 When a group call is established, the BSS broadcasts a Notification Command message on the NCH. The NCH is part of the CCCH. System Information Type 1 describes the position of NCH on the CCCH and contains the NCH Occupy Block Number and NCH Start Block parameters. The sum of NCH Occupy Block Number and NCH Start Block must be smaller than or equal to the value of CCCH Blocks Reserved for AGCH.

If NCH Occupy Block Number is set to 0, it indicates that the current cell does not support VGCS or VBS. In this case, System Information Type 1 does not provide information about the number of blocks occupied by the NCH or the start block.


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System Information Type 6 If a cell supports VGCS or VBS, the BSC needs to provide the NCH notification list of the current cell, the status of the list, whether the PCH has been adjusted, and some information about VGCS or VBS. If a cell supports Reduced NCH monitoring, an MS determines whether to listen to the NCH according to the Notification List Number (NLN) and the change in the list status. The MS need not listen to the NCH all the time, thus achieving the purpose of power saving.

System Information Type 6 is used in dedicated mode only.

System Information Type 10 System Information Type 10 is used to improve the cell reselection performance of an MS in group reception mode. Through System Information Type 10, only the information about neighboring cells in the same group call area is sent to MSs so that the MSs in group reception mode do not reselect the cell out of the group call area. Thus, call disconnections are minimized.

The cell list of a group call area is configured on the MSC side. Different group calls may have different cell lists. The cell list of a group call area is not configured on the BSC side. System Information Type 10 ensures that an MS reselects a cell within the group call area only. This improves the cell reselection performance of the MS. Therefore, when establishing a group call, the BSC indirectly constructs a cell list of the current group call according to the VGCS/VBS Assignment Request message from the MSC. Then, the BSC regards the intersection of the cell list of the current group call and the neighboring cell list of the current cell as the neighboring cell list of the current group call in the current cell. Through System Information Type 10, the BSC sends the MS the neighboring cell information of the current group call in the current cell. This information is intended as a reference for the MS to perform cell reselection.

One cell may belong to different group call areas and two or more group calls may be established in one cell. System Information Type 10 provides the MS in group reception mode with cell reselection information. Therefore, System Information Type 10 can be sent on only the corresponding SACCH of the NCH. The system information contains only the information about the neighboring cells that belong to the same group call area as the current cell.

BSS Idle Mode Behavior 4 Parameters


4-1

4 Parameters This chapter describes the parameters related to idle mode behaviour.

For the meaning of each parameter, see Table 4-1. For the default value, value ranges, and MML commands of each parameter, see Table 4-2.

Table 4-1 Parameter description (1)

Parameter Description

Minum Access RXLEV

Minimum received signal level of the MS. This level is reported in the system information.

MS_TXPWR_MAX_CCH

Maximum transmit power level of MSs. As one of the cell reselection parameters in system message 3, this parameter is used to control the transmit power of MSs. For details, see GSM Rec. 05.05. In a GSM900 cell, the maximum power control level of an MS ranges from 0 to 19, corresponding respectively to the following values (unit: dBm): 43, 41, 39, 37, 35, 33, 31, 29, 27, 25, 23, 21, 19, 17, 15, 13, 11, 9, 7, and 5. Generally, the maximum transmit power supported by an MS is level 5 (corresponding to 33 dBm). The minimum transmit power supported by an MS is level 19 (corresponding to 5 dBm). Other transmit power levels are reserved for high-power MSs. In a GSM1800 or GSM1900 cell, the maximum power control level of an MS ranges from 0 to 31, corresponding respectively to the following values (unit: dBm): 30, 28, 26, 24, 22, 20, 18, 16, 14, 12, 10, 8, 6, 4, 2, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 36, 34, and 32. Generally, the maximum transmit power supported by an MS is level 0 (corresponding to 30 dBm). The minimum transmit power supported by an MS is level 15 (corresponding to 0 dBm). Other transmit power levels are reserved for high-power MSs.

Power Deviation

If a class 3 MS on the DCS1800 band does not receive the original power command after random access, the power that the MS uses is the MS maximum transmit power level plus the power calculated from the power deviation. For details, see GSM Rec. 05.08.

Power Deviation Indication

The MS does not receive the original power command after random access. This parameter indicates whether the power deviation is added to the class 3 MS on the DCS1800 band on the basis of the maximum MS transmit power.

Cell Bar Qualify

Used together with "Cell Bar Access" to decide the priority status of a cell. See GSM Rec. 0408. This parameter does not affect cell reselection but cell selection only.

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Cell Access Bar Switch

Whether the cell can be added to the reselected candidate cell list. If this parameter is set to "NoPermit", the cell cannot be reselected as the candidate cell for handover. If this parameter is set to "Permit", the cell can be reselected as the candidate cell for handover.

Cell Reselect Hysteresis Parameters

Cell reselection hysteresis. This is one of the parameters used for deciding whether to reselect cells in different location areas. This parameter can avoid the increase of network signaling traffic due to frequent location update and reduce the risk of losing paging messages.

CCCH Blocks Reserved for AGCH

BS-AG-BLKS-RES, indicating the number of the CCCH message blocks reserved for the AGCH. After the CCCHs are configured, the value of this parameter indicates actually the seizure rates of the AGCHs and the PCHs over the CCCHs.

MS MAX Retrans

Maximum number of Channel Request messages that can be sent by an MS in an immediate assignment procedure. After the MS initiates the immediate assignment procedure, it always listens to the messages on the BCCH and all the common control channels (CCCHs) in the CCCH group to which the MS belongs. If the MS does not receive Immediate Assignment or Immediate Assignment Extend messages, it retransmits Channel Request messages at a specified interval. If the downlink quality is poor, the MS may send SABM frames to the BTS multiple times.

Cell Reselect Penalty Time

Cell Reselect Penalty Time (PT) is used to ensure the safety and validity of cell reselection because it helps to avoid frequent cell reselection. For details, see GSM Rec. 05.08 and 04.08.

Cell Reselect Offset

Cell Reselect Offset (CRO), indicating a correction of the C2. Proper setting of this parameter can reduce the number of handover times, helpful for assigning an MS to a better cell. In a special case that the PT is 31, the larger the CRO value is, the lower the possibility of handing over an MS to the cell. Generally, do not set the CRO to a value larger than 25 dB. The CRO with a too large value will cause uncertain states in a network. The CRO values of the cells with different priorities in a network are almost the same. Refer to GSM Rec. 05.08 and GSM Rec. 04.08. The setting of this parameter affects only the MSs supporting the protocol of GSM Phase 2 or a later version.

Cell Reselect Temporary Offset

Cell Reselect Temporary Offset (TO) indicates the temporary correction of C2. This parameter is valid only within the value specified by "Cell Reselect Penalty Time". For details, see GSM Rec. 05.08 and 04.08. This parameter applies to only GSM Phase II MSs.

Cell Reselect Parameters Indication

Cell Reselect Parameters Indication (PI), sent on the broadcast channel, indicates whether "Cell Reselect Offset", "Cell Reselect Temporary Offset" in the "SET GCELLIDLEAD" command, and "Cell Reselect Penalty Time" are used.



4-3


MCC

Mobile country code. This parameter identifies the country where a mobile subscriber is located, for example, the Chinese MCC is 460.

MNC Mobile network code. This parameter identifies the public land mobile network (PLMN) where a mobile subscriber is homed.

Cell LAC

Location area code (LAC). MSs can freely move in the local location area with no need of location update. Reasonable local allocation can effectively lighten the signaling load and improve the call completion rate. Can be input in hexadecimal format. The hexadecimal format is H'****, for example, H'1214.

Attach-detach Allowed

Attach-detach Allowed (ATT). If this parameter is set to YES, when a MS is powered off, the network does not process any call connection for the MS as a called party. In this way, the network processing time and resources are saved.

T3212 This parameter specifies the length of the timer for periodic location update.

Multi-Frames in a Cycle on the Paging CH

Number of multiframes in a cycle on a paging sub-channel. In fact, this parameter specifies the number of paging sub-channels that a paging channel in a cell is divided into. In an actual network, an MS does not listen to other paging sub-channels but its belonging paging sub-channel only. Refer to GSM Rec. 05.02 and GSM Rec. 05.08. The larger the value of this parameter, the more the number of the paging sub-channels in a cell, and the fewer the number of the users belonging to each paging sub-channel. In this case, the mean uptime of the MS battery can be prolonged. Refer to the computing mode of paging group in GSM 05.02 of GSM Standards. The larger the value of this parameter, however, the larger the time delay of a paging message in a space segment. Thus, the average service performance of the system lowers. Based on the principle of ensuring that overload does not occur to paging channels, you must set this parameter to a value as small as possible. You must regularly measure the overload conditions of the paging channels in a running network and accordingly adjust the value of this parameter properly. A paging message in a location area must be sent in all the cells within this location area at the same time. Therefore, the capacity of a paging channel of each cell in a location area must be the same or nearly the same. The capacity refers to the calculated number of paging sub-channels of each cell.

Support SPLIT_PG_CYCLE on CCCH

Whether to support SPLIT_PG_CYCLE on CCCH. The parameter SPLIT_PG_CYCLE is used to define the DRX period. You can specify whether the paging group based on SPLIT_PG_CYCLE is supported on CCCH for the BTS and the MS. Yes: the paging group based on SPLIT_PG_CYCLE is supported on CCCH. No: the paging group based on SPLIT_PG_CYCLE is not supported on CCCH.

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RAC

The NS performs location management based on routing areas during GPRS packet services. Each routing area has a routing area identifier, which is broadcast as a system message.

BTS Paging Lifetime

Lifetime of a paging message in the queue of the BTS. The setting of this parameter must be consistent with the setting of timer T3113 in the core network; otherwise, the efficiency of paging scheduling over the Um interface is reduced. It is recommended that this parameter be set to a value one to two seconds shorter than timer T3113. The units of this parameter is 250ms.

Paging Times

For the BTS, this parameter is used to determine paging retransmissions. This parameter and the number of paging times configured in the MSC determine the number of paging retransmissions. The total number of paging times is approximately equal to the value of this parameter multiplied by the number of paging times configured in the MSC.



4-5


TX-integer

TX-integer (T for short). This parameter specifies the number of timeslots between two transmissions when an MS sends multiple consecutive channel requests. The access algorithm is defined in GSM Rec. 04.08 to reduce the collisions on the RACH and improve the efficiency of the RACH. The algorithm specifies three parameters: TX-integer (T for short), maximum number of retransmissions (RET), and S related to channel combination. This parameter works with the configuration of the CCCH to determine the parameter S. The relations between this parameter and the configuration of the CCCH are as follows:

When this parameter is set to 3, 8, 14, or 50, S is 55 if the CCCH and SDCCH do not share a physical channel.

When this parameter is set to 3, 8, 14, or 50, S is 41 if the CCCH and SDCCH share a physical channel.

When this parameter is set to 4, 9, or 6, S is 76 if the CCCH and SDCCH do not share a physical channel.

When this parameter is set to 4, 9, or 6, S is 52 if the CCCH and SDCCH share a physical channel.







The timeslot for sending messages is a random value from the collection of {0, 1..., MAX(T, 8)-1}. The number of timeslots (excluding the timeslot used to send messages) between two adjacent channel request messages is a random value from the collection of {S, S+1, ..., S+T-1}. When T increases, the interval between two adjacent channel requests increases, and RACH conflicts decrease. When S increases, the interval between two adjacent channel request messages increases, and RACH conflicts decrease, thus improving the usage of AGCH and SDCCH. The access time of the MS, however, is prolonged and the network performance is decreased when T and S increase. Under normal conditions, an appropriate T value should be used to ensure that S is as low as possible, and ensure that AGCH and SDCCH are not overloaded.

4 Parameters BSS

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Common Access Control Class

Level of common access control, used for load control, allowing or forbidding the access of some users of common access levels

Special Access Control Class

This parameter is used for load control. It determines whether the users of special access class are allowed to access the network. Value 1 indicates that access is not allowed. Value 0 indicates that access is allowed.

Call Reestablishment Forbidden

Whether to allow call re-establishment. Burst interference or blind spots due to high buildings may lead to a radio link failure. If a call drop is caused by such a failure, the MS can start call re-establishment to resume the conversation.

Emergent Call Disable

Whether to disable emergency calls. For the MSs of access levels 0 to 9, if the value of this parameter is NO, emergency calls are enabled. For the MSs of access levels 11 to 15, emergency calls are disabled only when the relevant access control bit is set to 0 and this parameter is set to YES.

Send System Information 2ter

Whether the BSC sends the System Information Type 2ter message.

SI 2ter Switch

Whether the BSC sends a System Information Type 2ter message to a non-dualband cell. When the parameter is set to YES, the cell does not send the System Information Type 2ter message if the cell is not configured with inter-frequency neighboring cells. If the cell is configured with inter-frequency neighboring cells, the cell sends the System Information Type 2ter message. When the parameter is set to NO and "Send System Information 2ter " is set to YES, the cell sends the System Information Type 2ter message. Otherwise, the cell does not send the message.

Support Sent 2QUATER

This parameter specifies whether the SI Type 3 message contains the 2QUATER indicator.

NCC Permitted

A set of NCCs of the cells to be measured by the MS. This parameter is an information element (IE) in the system information type 2 and 6 messages. If a bit of the value of this parameter is set to 1, the MS reports the corresponding measurement report to the BTS. The value of this parameter has a byte (eight bits). Each bit maps with an NCC (0~7) and the most significant bit corresponds to NCC 7. If bit N is 0, the MS does not measure the cell level of NCC N.

Multi-band report

Used for requesting the MS to report the measurement information of neighboring cells in multiple frequency bands. This parameter is carried in the system information 2ter and 5ter.

Cell CI

Identity code of a cell. A cell is a wireless coverage area identified by a base station identity code and a global cell identification. Can be input in hexadecimal format. The hexadecimal format is H'****, for example, H'1214.



4-7


MSC Version Indication

Protocol version of the MSC that is connected to the BSC6900. The supported signaling varies with the protocol versions.

PWRC

Whether an MS uses the calculated value as the final receive level value. The calculated receive level value is the measured receive level value minus the receive level value obtained from the BCCH TRX timeslots. This parameter is a cell option in system messages 3 and 6.

FR Uplink DTX Whether the uplink DTX function is enabled for FR calls. For details, see GSM Rec. 05.08.

Radio Link Timeout

Time for disconnecting a call when the MS fails to decode the SACCH. Once a dedicated channel is assigned to the MS, the counter S is enabled and the initial value is set to this parameter value. Each time an SACCH message is not decoded, the counter S decreases by 1. Each time an SACCH message is correctly decoded, the counter S increases by 2. When the counter S is equal to 0, the downlink radio link is considered as failed. Therefore, when the voice or data quality is degraded to an unacceptable situation and it cannot be improved through power control or channel handover, the connection is to be re-established or released.

Additional Reselect Parameter Indication

Used for notifying MSs where they retrieve relevant cell reselection parameters during cell reselection. The value of this parameter is 0 in system message 3, without any meaning. In system message 4, the value 0 of this parameter means MSs must retrieve the PI parameters and other parameters relevant to cell reselection and the parameters relevant to C2 calculation from the remaining bytes of system message 4. The value 1 means that the MS must retrieve the parameters from the remaining bytes of system message 7 or 8.

Support Half Rate

Whether to support the half-rate service in this cell. It is one of the cell reselection parameters in system message 3.

ECSC

The early classmark sending control (ECSC) parameter specifies whether the MSs in a cell use early classmark sending. After a successful immediate assignment, the MS sends additional classmark information to the network as early as possible. The additional classmark information mainly contains the CM3 (classmark 3) information. The CM3 (classmark 3) information contains the frequency band support capability of the MS (used for the future channel assignment), power information about each frequency band supported by the MS (used for the handover between different frequency bands), and encryption capability of the MS.

GPRS Whether the current cell supports GPRS.

Routing Area Color Code Routing area color code of the GPRS cell.

4 Parameters BSS

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Packet Access Priority

Access priority of the MS that is allowed to access the cell. The MS sends the packet channel request containing the 2-bit radio priority message. The priority of the 2-bit radio priority message ranges from 1 to 4 in descending order. During the MS access, the BSC compares the radio priority in the channel request with the parameter setting of the cell. If the radio priority equals to the parameter setting of the cell, the BSC sets up the TBF for the channel request.

Network Control Mode

Network control mode for cell reselection of the MS. There are three modes. NC0: normal MS control. The MS shall perform autonomous cell re-selection. NC1: MS control with measurement reports. The MS shall send measurement reports to the network and the MS shall perform autonomous cell re-selection. NC2: network control. The MS shall send measurement reports to the network . The MS shall only perform autonomous cell re-selection when the reselection is triggered by a downlink signalling failure or a random access failure.When this parameter is set to NC2 and "Support NC2" in [mml]SET GCELLGPRS[/mml] is set to "YES", the network side can control the cell reselection for the MS.

PSI1 Repetition Period

Period for sending the packet message PSI. If the period is too long, the message PSI cannot be obtained in realtime. If the period is too short, the message PSI is broadcast frequently, which occupies too much system resources.

NCH Occupy Block Number Number of blocks occupied by the NCH in the group call service

NCH Start Block Number of the start block occupied by the NCH in the group call service

Table 4-2 Parameter description (2)

Parameter

Default Value

GUI Value Range

Actual Value Range

Unit MML Command Impa

ct

Minum Access RXLEV 8 0~63 0~63 dB

SET GCELLBASICPARA(Optional) Cell

MS_TXPWR_MAX_CCH 5 0~19 0~19 None

SET GCELLCCCH(Optional) Cell

Power Deviation 1 0~3 0~3 None

SET GCELLCCACCESS(Optional) Cell



4-9

GUI Actual MML Command Paramete Default Impar Value Value

Range Value Unit ct Range

Power Deviation Indication YES

NO(No), YES(Yes)

NO, YES None

SET GCELLCCACCESS(Optional) Cell

Cell Bar Qualify NO

NO(No), YES(Yes)

NO, YES None

SET GCELLIDLEBASIC(Optional) Cell

Cell Access Bar Switch Permit

Permit(Permit Cell Access), NoPermit(Prohibit Cell Access)

Permit, NoPermit None

SET GCELLSERVPARA(Optional) Cell

Cell Reselect Hysteresis Parameters 6dB

0dB, 2dB, 4dB, 6dB, 8dB, 10dB, 12dB, 14dB

0dB, 2dB, 4dB, 6dB, 8dB, 10dB, 12dB, 14dB dB


CCCH Blocks Reserved for AGCH 1 0~7 0~7 None


MS MAX Retrans

4_Times

1_Times(1_Times), 2_Times(2_Times), 4_Times(4_Times), 7_Times(7_Times)

1_Times, 2_Times, 4_Times, 7_Times None

SET GCELLCCBASIC(Optional) Cell

Cell Reselect Penalty Time 0 0~31 0~31 s

SET GCELLIDLEAD(Optional) Cell

Cell Reselect Offset 0 0~63

0~126, step: 2 dB


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Cell Reselect Temporary Offset 0 0~7 0~7 None


Cell Reselect Parameters Indication YES

NO(No), YES(Yes)

NO, YES None


MCC None None 3 digit None

ADD GCNOPERATOR(Mandatory) ADD GCELL(Mandatory) ADD GEXT2GCELL(Mandatory) ADD GEXT3GCELL(Mandatory) SET FHO(Mandatory) ADD BTSAUTOPLAN(Mandatory) SET BTSAUTOPLANCFG(Optional) ADD GCELLQUICKSETUP(Mandatory) Cell

MNC None None 2~3 digit None

ADD GCNOPERATOR(Mandatory) ADD GCELL(Mandatory) ADD GEXT2GCELL(Mandatory) ADD GEXT3GCELL(Mandatory) SET FHO(Mandatory) Cell



4-11



Cell LAC None 1~65533,65535

1~65533, 65535 None

ADD GCELL(Mandatory) ADD GEXT2GCELL(Mandatory) ADD GEXT3GCELL(Mandatory) SET FHO(Mandatory) ADD BTSAUTOPLAN(Mandatory) SET BTSAUTOPLANCFG(Optional) ADD GCELLQUICKSETUP(Mandatory) Cell

Attach-detach Allowed YES

NO(No), YES(Yes)

NO, YES None


T3212 20 0~255 0~1530, step: 6 min


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Multi-Frames in a Cycle on the Paging CH

2_M_PERIOD

2_M_PERIOD(2 Multiframe Period), 3_M_PERIOD(3 Multiframe Period), 4_M_PERIOD(4 Multiframe Period), 5_M_PERIOD(5 Multiframe Period), 6_M_PERIOD(6 Multiframe Period), 7_M_PERIOD(7 Multiframe Period), 8_M_PERIOD(8 Multiframe Period), 9_M_PERIOD(9 Multiframe Period)

940~4230, step: 470 ms


Support SPLIT_PG_CYCLE on CCCH NO

NO(NO), YES(YES)

NO, YES None

SET GCELLPSBASE(Optional) Cell

RAC 0 0~255 0~255 None

ADD GEXT2GCELL(Optional) Cell



4-13



BTS Paging Lifetime 255 0~255 0~255 ms

SET GCELLSOFT(Optional) Cell

Paging Times 4 1~8 1~8 None


TX-integer TX_32

TX_3(3), TX_4(4), TX_5(5), TX_6(6), TX_7(7), TX_8(8), TX_9(9), TX_10(10), TX_11(11), TX_12(12), TX_14(14), TX_16(16), TX_20(20), TX_25(25), TX_32(32), TX_50(50)

TX_3, TX_4, TX_5, TX_6, TX_7, TX_8, TX_9, TX_10, TX_11, TX_12, TX_14, TX_16, TX_20, TX_25, TX_32, TX_50 None


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Common Access Control Class

L0_FORBID-0&L1_FORBID-0&L2_FORBID-0&L3_FORBID-0&L4_FORBID-0&L5_FORBID-0&L6_FORBID-0&L7_FORBID-0&L8_FORBID-0&L9_FORBID-0

L0_FORBID, L1_FORBID, L2_FORBID, L3_FORBID, L4_FORBID, L5_FORBID, L6_FORBID, L7_FORBID, L8_FORBID, L9_FORBID

L0_FORBID, L1_FORBID, L2_FORBID, L3_FORBID, L4_FORBID, L5_FORBID, L6_FORBID, L7_FORBID, L8_FORBID, L9_FORBID None


Special Access Control Class

L11_FORBID-0&L12_FORBID-0&L13_FORBID-0&L14_FORBID-0&L15_FORBID-0

L11_FORBID, L12_FORBID, L13_FORBID, L14_FORBID, L15_FORBID

L11_FORBID, L12_FORBID, L13_FORBID, L14_FORBID, L15_FORBID None


Call Reestablishment Forbidden YES

NO(No), YES(Yes)

NO, YES None


Emergent Call Disable NO

NO(No), YES(Yes)

NO, YES None


Send System Information 2ter NO

NO(No), YES(Yes)

NO, YES None

SET OTHSOFTPARA(Optional) BSC

SI 2ter Switch YES

NO(No), YES(Yes)

NO, YES None




4-15



Support Sent 2QUATER YES

NO(No), YES(Yes)

NO, YES None


NCC Permitted

SELECTION0_PERM-1&SELECTION1_PERM-1&SELECTION2_PERM-1&SELECTION3_PERM-1&SELECTION4_PERM-1&SELECTION5_PERM-1&SELECTION6_PERM-1&SELECTION7_PERM-1

SELECTION0_PERM, SELECTION1_PERM, SELECTION2_PERM, SELECTION3_PERM, SELECTION4_PERM, SELECTION5_PERM, SELECTION6_PERM, SELECTION7_PERM

SELECTION0_PERM, SELECTION1_PERM, SELECTION2_PERM, SELECTION3_PERM, SELECTION4_PERM, SELECTION5_PERM, SELECTION6_PERM, SELECTION7_PERM None


Multi-band report 0 0~3 0~3 None


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Cell CI None 0~65535

0~65535 None

ADD GCELL(Mandatory) ADD GEXT2GCELL(Mandatory) ADD GEXT3GCELL(Mandatory) SET FHO(Mandatory) ADD BTSAUTOPLAN(Mandatory) SET BTSAUTOPLANCFG(Optional) ADD GCELLQUICKSETUP(Mandatory) Cell

MSC Version Indication

R98_or_below

R98_or_below(R98 or below), R99_or_above(R99 or above)

R98_or_below, R99_or_above None

SET GCELLCCUTRANSYS(Optional) Cell

PWRC YES

NO(No), YES(Yes)

NO, YES None


FR Uplink DTX

Shall_Use

May_Use(May Use), Shall_Use(Shall Use), Shall_NOT_Use(Shall not Use)

May_Use, Shall_Use, Shall_NOT_Use None




4-17



Radio Link Timeout

52_Times

4_Times, 8_Times, 12_Times, 16_Times, 20_Times, 24_Times, 28_Times, 32_Times, 36_Times, 40_Times, 44_Times, 48_Times, 52_Times, 56_Times, 60_Times, 64_Times

1920~30720, step: 480 ms


Additional Reselect Parameter Indication FLEX

COMPUL0(Compulsory 0), COMPUL1(Compulsory 1), FLEX(Flexible)

COMPUL0, COMPUL1, FLEX None


Support Half Rate NO

NO(No), YES(Yes)

NO, YES None


ECSC YES

NO(No), YES(Yes)

NO, YES None


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GPRS None

NO(Not support), SupportAsInnPcu(Support as built-in PCU), SupportAsExtPcu(Support as external Pcu)

NO, SupportAsInnPcu, SupportAsExtPcu None

SET GCELLGPRS(Mandatory) Cell

Routing Area Color Code 1 0~7 0~7 None


Packet Access Priority 6

0(No packet access), 3(Packet access of level 1), 4(Packet access of levels 1-2), 5(Packet access of levels 1-3), 6(Packet access of level 1-4)

0, 3, 4, 5, 6 None


Network Control Mode NC0

NC0(NC0), NC1(NC1), NC2(NC2)

NC0, NC1, NC2 None


PSI1 Repetition Period 6 1~16 1~16 None

SET GCELLPSI1(Optional) Cell



4-19



NCH Occupy Block Number 0 0~7 0~7 None

SET GCELLGSMR(Optional) Cell

NCH Start Block 0 0~7 0~7 None

SET GCELLGSMR(Optional) Cell

BSS Idle Mode Behavior 5 Counters


5-1

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

BSS Idle Mode Behavior 6 Glossary


6-1

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

BSS Idle Mode Behavior 7 Reference Documents


7-1

7 Reference Documents 3GPP TS 23.122 Non-Access-Stratum (NAS) functions related to Mobile Station (MS) in idle mode 3GPP TS 44.018 Mobile radio interface layer 3 specification; Radio Resource Control (RRC) protocol

3GPP TS 45.008 Radio subsystem link control 3GPP TS 43.022 Functions related to Mobile Station (MS) in idle mode and group receive mode BSC6900 Feature List BSC6900 Basic Feature Description BSC6900 Optional Feature Description BSC6900 GSM Parameter Reference BSC6900 GSM MML Command Reference BSC6900 GSM Performance Counter Reference

idle mode behavior

Documents

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automatic plmn selection

manual plmn selection

gsm cell reselection

technical description