8.gsm radio parameter

8/4/2019 8.Gsm radio parameter

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2012年4月18日 1

ZXG10Radio Parameters

ZXG10 System



2012年4月18日 2

Contents

Network Identification Parameters（CGI,

BSIC )

System Control Parameters（RLT, CBA,

CBQ, etc )

Cell Selection Parameters ( C1, C2 )

Network Functional Parameters (INTAVE,

LIMITn, etc )



2012年4月18日 3

Network identification Parameters

As a global cellular mobile communication

system, the GSM strictly numbers each GSM

network in each country, or even numbers each

location area, every station or every cell inevery network in order that every cell around

the globe has an sole corresponding number.

This numbering mode aims to:



2012年4月18日 4

Roles of Network Identification

Parameters

Enable the MS to correctly identify the ID of the current

network so that it can correctly select the network the user (or

telecom operator) wants to access to in any conditions.

Enable the network to be real time informed of the correct

geographical location of the MS so that the network can

normally connect various service requests with the MS as the

terminal.

Enable the MS to report correctly the adjacent cell information

during the conversation process so that the network can hand-over the calls when necessary to ensure the continuity of the

conversation.


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Cell Global Identity（CGI）

CILACMNC

LAI

CGI

MCC



Setting of CGI

MCC resource is allocated and managed by ITU. The MCC of

China is 460（decimal).

MNC is usually allocated by the relevant telecommunication

administration department of a country.

The LAC encoding mode is specified correspondingly by every

country. Usually, the location area should be as large as possible.

Two or more cells in the same location area are not allowed to

share the same CI.



BSIC(1)

In GSM system, each BS is allocated with a local

color code called base station identity code (BSIC). If,

in a physical location, one MS can receive the BCCH

TRX of two cells at the same time and their channel

numbers are the same, the MS will distinguish them by

the BSIC.



2012年4月18日 10

BSIC(2)

BCC

BSIC

NCC

BSIC is composed of NCC(network color code) and

BCC(base station color code).

NCC ranges from 0～7. BCC ranges from 0～7.



2012年4月18日 11

NCC and BCC

In the connection mode (during conversation), the MS must measure the

signals in the adjacent cells and report the result to the network. As each

measurement report sent by the MS can only contain the contents of six

cells, so it is necessary to control the MS so as to only report the

information of cells factually related to the cell concerned. The high 3bits (i.e. NCC) in the BSIC serve this purpose.

The BCC is used to identify different BS using the same BCCH in the

same GSMPLMN.



2012年4月18日 12

BSIC Configuration Principle

CBA

FED

In general, it is required that Cells A, B, C, D, E and F use

different BSIC. When the BSIC resources are not enough,

the cells close to each other may take the priority to use

different BSIC.



2012年4月18日 13

Roles of BSIC(1)

1. When MS receives the SCH, it is considered to havesynchronized with the cell. But in order to correctly translate

the information on the downlink common signaling channel,

the MS must be aware of the training sequence code (TSC)

used by the common signaling channel. The TSC used by the

common signaling channel of each cell is determined by the

BCC. So one of the functions of the BSIC is to inform the MS

the TSC used by the common signaling channel of the cell.

2. As the BSIC takes part in the decoding process of the

random access channel (RACH), it can be used to prevent theBS from mis-decoding the RACH, sent by the MS to an

adjacent cell, as the access channel of this cell.



2012年4月18日 14

BSIC(2)

3. When the MS is in the connection mode (during

conversation), it must measure the BCCH level of

adjacent cells specified in adjacent cell tables

broadcasting by BCCH and report the results to the BS.

In the uplink measurement report, MS must show BSIC

of this carrier it has measured to every frequency point.

In some special cases, i.e. two or more adjacent cells in a

cell use the same BCCH, the BS can distinguish such

cells by way of BSIC in order to avoid the wrong

handover or even the handover failure.



2012年4月18日 15

BA

When a MS is turned on, it will scan from the

BA (Adjacent cell BCCH table) it remembered

when turned off last time. The MS will first

search carriers from this table and if none isfound it will turns to find any of 30 carriers with

highest levels, then try to decode BCCH carriers

one by one according to their level sequences.



2012年4月18日 16

Cell Selection

When the MS is turned on, it will try to contact a

public GSM PLMN, so the MS will select a

proper cell and extract from the cell the control

channel parameters and prerequisite systemmessages. This selection process is called cell

selection. The quality of radio channels is an

important factor in cell selection. The GSM

Specifications defines the path loss rule C1.Forthe so-called proper cell, C1>0 must be ensured.



2012年4月18日 17

C1

C1 = RXLEV - RXLEV_ACCESS_MIN- Max(MS_TXPWR_MAX_CCH - P ,0)where,RXLEV_ACCESS_MIN is the minimum received level

the MS is allowed to access the network MS_TXPWR_MAX_CCH is the maximum power level of

the control channel (when MS sending on RACH);

RXLEV is average received level; P is the maximum TX power of MS;

MAX（X, Y）＝X; if X Y.

MAX（X, Y）＝Y; if Y X.



2012年4月18日 18

Path loss Criterion:

All the candidate cells for MS must meet the

path loss criterion, i.e C1>0. MS will select the

cell with the maximal C1 to access and will

camp on this cell unless some key conditionshas changed greatly.



2012年4月18日 19

RXLEV_ACCESS_MIN）

In order to avoid providing unsatisfactory communicationquality and avoid the unnecessary waste of radio resources if

the MS accesses to the system (the communication quality

after the access often cannot ensure the normal

communication process) at the very low received level, theGSM system regulates that, when a MS is to access to a

network, its receiving signal level must be larger than a

threshold level, i.e. the minimum receiving level the MS is

allowed to access to（RXLEV_ACCESS_MIN). Defaultvalue is 0 (-110dBm).



2012年4月18日 20

Cell Reselection

The necessity to make a cell reselection Parameters regarding to cell reselection

PI

C2

Cell Selection Hysteresis

CRO、TO and PT

CBA

CBQ



2012年4月18日 21

Definition

Cell reselection is a process MS change its service cell in idle

mode. When the MS selects a cell and if there are not major

changes in the various conditions, the MS will stay in the

selected cell, and the MS will begin to measure the signal

levels of the BCCH TRX of its adjacent cells, record 6adjacent cells whose signal levels are the strongest and

extract from them various types of system messages and

control messages of each adjacent cell. When given

conditions are met, the MS will move from the current cell

into another one. This process is called cell reselection.



2012年4月18日 22

C2（1）

When PI indicates YES，the MS will get

parameters (CRO, TO and PT) , from BCCH, to be

used to calculate C2(channel quality criterion),

which serves as cell reselection norm. The equation

is as follows:

C2＝C1＋CRO－H（PT－T）×TO, when PT 31

C2＝C1－CRO , when PT＝31

Where T is a timer. When a cell is recorded by MS as

one of the six strongest cells,timer starts counting,otherwise, T is reset to zero.



2012年4月18日 23

PI

PI is used to notify the MS whether to use C2 as the

cell reselect parameter and whether the parameters

calculating C2 exist.

PI consists of 1 bit. “1”means the MS should extractparameters from the system message broadcasting in

the cell to calculate the C2 value, and use the C2 value

as the standard for cell reselect; “0” means the MS

should use parameter C1 as the standard for cellreselect (equivalent to C2＝C1）.



2012年4月18日 24

C2（2）

If the MS calculates that the C2 value of an adjacent cell (in the

same location area with the current cell) surpasses the C2 value

of the cell where the MS stays and maintains for 5s or longer,

the MS will start cell reselection and access to the adjacent cell.

If the MS detects a cell that is not in the same location area withthe current cell, the calculated C2 value surpasses the sum of the

C2 value of the current cell and the cell selection hysteresis

(CSH) parameter and if it remains for 5s or longer, the MS will

start the cell reselection and access to the new cell. Note that

the cell reselection caused by the parameter C2 should beoriginated at least at the interval of 15s so as to avoid the

frequent cell reselection by MS.



2012年4月18日 25

CELL SELECTION HYSTERESIS(1)

When a MS reselects a cell, if the old cell and the targetcell are in different locations, then the MS must initiate a

location updating process after cell reselection. Due to the

fading features of the radio channel, the C2 values of two

adjacent cells measured along their borders will fluctuategreatly. As a result, the MS will frequently conduct the

cell reselection, which will not only increase the network

signaling flow and lead to low efficiency use of radio

resources, but reduces the access success rate of thesystem, as the MS cannot respond to paging calls in the

location updating process.



2012年4月18日 26

CELL SELECTION HYSTERESIS(2)

To minimize the influence of this issue, the GSMspecifications put forward a parameter called cell

selection hysteresis (CSH), which requires that the

signal level of adjacent cell (in a different location area)

be larger than the local cell signal level, and theirdifference be larger than the value specified by the cell

selection hysteresis. In this case, the MS will start the

cell reselection.

The cell selection hysteresis is represented in decimalnumerals, its unit is dB, its range is 0～14, its step

length is 2dB, and its default value is 4.



2012年4月18日 27

CRO,TO and PT（1）

The cell reselection initiated by the radio channel quality

regards C2 as the standard. C2 is a parameter based on C1

plus some artificial offset parameters. The artificial

influence is to encourage the MS to take the priority in

accessing to some cells or prevent it from accessing toothers. These methods are often used to balance the traffic

in the network.

In addition to C1, there are three other factors influencing

C2, namely: CELL_RESELECT_OFFSET (CRO),TEMPORARY_OFFSET (TO) and PENALTY_TIME

(PT).



2012年4月18日 28


The adjustments of above 3 parameters are as

followed:.

1. In general, it’s not expected that MS access the

cells where the traffic is very heavy or the channel

quality is very low. In this case , the PT may be set

31, making TO invalid, so C2=C1-CRO. Because

the C2 is lowered deliberately, the possibility that

the cell will be reselected by MS is lowered greatly.

The greater the CRO, the less possibility that the

cell will be reselected, and vice versa.



2012年4月18日 29


2. On the other hand, it’s expected that MS stay as much as

possible in cells where the system utilization are very low

and the traffic load is light. In this case, it’s recommended

that CRO be ranged from 0 to 20dB. The greater the CRO,

the more possible the cells will be reselected ,and vice versa.It’s also suggested that TO is equal or a litter higher than

CRO. PT, whose main role is to avoid frequent cell

reselection by MS, is generally recommended to be set at 20

seconds or 40 seconds.

3. For cells where the traffic is moderate, the recommendedvalue for CRO is zero and PT 620 seconds, thus causing

C2=C1, i. e. no artificial impact will be imposed.



2012年4月18日 30

CBA

In the system message broadcasting in each cell, there is a bit

information indicating whether to allow the MS to access to it, which

is called cell bar access (CBA). The parameter CBA is to indicate

whether the cell bar access is set in a cell.

The parameter is represented in character string. Its value range is:

YES: Set the CBA; NO: Do not set the CBA.

The CBA bit is a parameter for the network operator to set. Usually

all the cells are allowed to be accessed by MS , so the bit is set NO.

However, in special cases, the telecom operator may want to assign a

certain cells for handover service only, then the bit can be set YES.



2012年4月18日 31

Application of CBA(1)

Area A

BTS A

BTS B

BTS C



2012年4月18日 32


Suppose Area A (shaded part) in the figure is

the busy area (e.g. commercial area in a large

city), we usually adopt the micro cellular mode

to increase the access rate of the area via thelimited frequency resources. We often use the

double layer network concept, i.e. to set up BTS

A (its capacity can be smaller) to cover the

whole Area A, in order to reduce the handoff

times while the MS is moving rapidly.



2012年4月18日 33


In general situations, the MS works in the micro

cellular (you can set the priority of the cell and

proper reselect parameter to achieve this

purpose). When the MS is moving at a fastspeed during a conversation, the network will

force the MS to be handed over to BTS A.



2012年4月18日 34


If the MS is just near BTS A and at the edge of a micro

cellular after the conversation, the MS will not start the cell

reselect process according to the GSM specifications because

the signal quality of BTS A is far better than that of the micro

cellular BTS . As a result, the MS cannot return to the micro

cellular cell. As the capacity of BTS A is usually smaller, the

above situation will lead to the congestion of BTS A. To

solve this problem, you can set the CBA of BTS A as 1, that

is to forbid the MS from directly accessing to BTS A, andpermit only the handover service to access to the coverage of

BTS A.



2012年4月18日 35

CBQ

In areas where the cells overlay with each other and differ in

capacity, traffic and functions, the telecom operator often hopes that

the MS can have priority in selecting some cells, that is, the setting

of cell priority. This function is set by way of the parameter "Cell

Bar Qualify" (CBQ). CBQ CBA Cell selection priority Cell reselection state

NO NO Normal Normal

NO YES Barred Barred

YES NO Low Normal

YES YES Low Normal



2012年4月18日 36

Example of CBQ Setting

B

For some reasons, the traffic of Cells A and B is apparently higher

than that of other adjacent cells. To balance the traffic in the wholearea, you can set the priority of Cells A and B as low, and set the

priority of the rest cells as normal so that the traffic in the shade area

will be absorbed by adjacent cells. It must be noted that the result of

this setting is that the actual coverage of Cell A and Cell B is

narrowed. However, this is dissimilar to reducing the transmittingpower of Cell A and Cell B, the latter may cause blind areas of the

network coverage and the reduction of communication quality.。



2012年4月18日 37

Random Access

Random access is the process that messages being transmitted on RACH

when a MS turns from “idle” to “specialized” mode. The main parameters

includes:

* MAX RETRANS* AC

* RE



2012年4月18日 38

MAX RETRANS(1)

When starting the immediate assignment process (e.g,when MS needs location updating, originating calls or

responding to paging calls), the MS will transmit the

"channel request" message over the RACH to the

network. As the RACH is an ALOHA channel, inorder to enhance the MS access success rate, the

network allows the MS to transmit multiple channel

request messages before receiving the immediate

assignment message. The numbers of maximumretransmission (MAX RETRANS) are determined by

the network.



2012年4月18日 39

MAX RETRANS(2)

The MAX RETRANS is often set in the following ways:

For areas (suburbs or rural areas) where the cell radius is more

than 3km and the traffic is smaller, the MAX RETRANS can be

set 11(i.e. the MAX RETRANS is 7).

For areas (not bustling city blocks) where the cell radius is less

than 3km and the traffic is moderate, the MAX RETRANS can

be set 10（i.e. the MAX RETRANS is 4）.

For micro-cellular, it’s recommend that the MAX RETRANS be

set 01（i.e. the MAX RETRANS is 2）.

For microcellular areas with very high traffic and cells with

apparent congestion, it’s recommend that the MAX RETRANS

be set 00（i.e. the MAX RETRANS is 1).



2012年4月18日 40

Access Control (AC)(1)

In some special conditions, the telecom operator wants to bar all or partof MS from sending out the access request or paging response request in

some special areas. For example, in case some areas are in emergency

state or in case a GSM PLMN encounters a serious fault. For this reason,

GSM Specification（02.11）stipulates that each GSM subscriber

(ordinary subscriber) is allocated with an access level. The access levelranges from 0 to 9 and is stored in the SIM card of the subscriber. The

GSM Specifications reserves 5 special access levels for some special

subscribers, which range from 11 to 15. These levels usually have higher

access priority. Special subscribers can have one or more access levels

(11~15), and their access levels are also stored in the SIM cards.



2012年4月18日 41

AC(2)

The access levels are distributed as follows: C 0～C9: ordinary subscribers;

C11: used for PLMN management;

C12: used by the security department;

C13: public utilities（e.g. water, gas）;

C14: emergency service;

C15: PLMN staff.



2012年4月18日 42

Setting of AC

In the BS installation and commissioning process or in theprocess of maintaining or testing some cells, the operator can set

C0～C9 as 0 to forcedly forbid the access of ordinary

subscribers so as to reduce the unnecessary effects on the

installation or maintenance work.

In some cells with very high traffic, the congestion will occur in

busy hours. For example, the RACH conflict happens

frequently, the AGCH is overloaded and the Abis interface flow

is overloaded. The network operator can set proper access

control parameters（C0～C15）to control the traffic of somecells.

i



2012年4月18日 43

Reestablishment Enable（RE）

For the drop calls caused by the radio link fault due to the burstinterference or blind areas owing to the high rise buildings, the

MS can start the call reestablishment process to resume the

conversation, but the network is entitled to determine whether

the call reestablishment is allowed or not. “0”=Yes, “1”=No.

In some special circumstances, the drop call may occur when the MS goes

through a blind area during the conversation. If the call reestablishment is

allowed, the mean drop call rate will be reduced. However, the call

reestablishment process will occupy a longer period of time, most of the

subscribers have hung up before the reestablishment process is over, as a

result, the call reestablishment failed to achieve its purpose and wasted manyradio resources. We recommend that the call reestablishment be not allowed

in the network except for some individual cells.

LIMIT (1)



2012年4月18日 44

LIMITn(1)

According to GSM Specification 05.08, the BTS must measure theinterference levels of the upward links of all the free channels for the

purpose of providing basis for managing and allocating radio resources.

Moreover, the BTS should analyze its measured results, divide the

interference levels into 5 grades and report them to the BSC. The

division of the 5 interference grades (i.e. the so-called interferencebands) is set by the operator through the man-machine interface. The

parameter "Interference band border(LIMITn)” determines the borders

of the 5 interference bands.

S tti f LIMIT



2012年4月18日 45

Setting of LIMITn

0 <-110dBm1 -110dBm－ -109dBm

2 -109dBm－ -108dBm

… …

61 -50dBm－ -49dBm

62 -49dBm－ -48dBmDefault: LIMIT1：4 LIMIT2：8 LIMIT3：15 LIMIT4：25

The division of the interference bands should be favorable in describing

the interference in the system. Generally the default values are

recommended. In the ordinary situations, the free channel interference

level is smaller, so the LIMIT1～4 value should be smaller. When

apparently large interference appears in the system, you can properly

increase the LIMIT1~4 values in order to know the exact interference.

IMSI Att h/D t h(ATT) 1



2012年4月18日 46

IMSI Attach/Detach(ATT)（1）

The IMSI detach process is that: the MS notifies the network that it is

moving from the working state to the non-working state, or the processof the SIM card being taken from the MS. When receiving the

notification from the MS, the network will indicate the IMSI subscriber

to be in the non-working state, so the connection request ending the

subscriber as the called party will be rejected. The corresponding IMSI

attach process is that the MS notifies the network that it has been in theworking state , or the SIM card is re-inserted into the MS. When the MS

re-enters the working state, it will detect whether the current LAI is the

same as the LAI finally recorded in the MS. If they are the same, the MS

will start the IMSI attach process, otherwise the MS will start the

location updating process (instead of the IMSI attach process). When

receiving the location updating or IMSI attach process, the network will

indicate the IMSI subscriber being in the working state.

IMSI Att h/D t h(ATT) 2



2012年4月18日 47

IMSI Attach/Detach(ATT)（2）

An ATT mark should be set as YES so that the network will no longerprocess the connection process using the MS as the called after the

MS shuts down, thus saving the processing time of the network

entities and saving lots of network resources.

Please note that the ATT in different cells but in the same locationarea should be set the same. Because the shutdown of the MS in cells where

the ATT is YES will start the IMSI detach process, and the network will record the

fact that the MS is in the non-working state and reject all the connection requests

when using MS as the called. When the MS restarts and is in the same location area

(so the location update process is not started) as when it shuts down but is in a

different cell and the ATT of the cells is set as NO, so the MS will not start the IMSIattach process, either. In this case, the MS cannot become the called party until it

starts the location updating process.

CCCH CONF



2012年4月18日 48

CCCH_CONF

The CCCH can be one or more physical channels. TheCCCH and SDCCH can share the same physical channel.

The combination mode of the common control channel in a

cell is determined by the CCCH_CONF.

CCCH_CONF Coding Meanings CCCH message blocks in one BCCH

000 CCCH use one basic physical channel, not shared with SDCCH 9

001 CCCH use one basic physical channel, shares with SDCCH 3

010 CCCH use two basic physical channels, not shared with SDCCH 18

100 CCCH use three basic physical channels, not shared with SDCCH 27

110 CCCH use 4 basic physical channels, not shared with SDCCH 36

Others Reserved

Setting and Impact of CCCH CONF



2012年4月18日 49

Setting and Impact of CCCH_CONF

The CCCH_CONF is determined by the telecomoperation department according to the traffic model

of a cell. It is often decided in the system design

period. According to the ordinary experience, if acell has 1 or 2 TRX, we recommend that the CCCH

uses one basic physical channel and shares it with

the SDCCH; if a cell has 3 or 4 TRX, we

recommend that the CCCH uses one basic physicalchannel but does not share it with the SDCCH.

AGBLK



2012年4月18日 50

AGBLK

Since the CCCH consists of the access grant channel (AGCH)and paging channel (PCH), it is necessary to set how many

blocks of the CCCH information blocks are reserved and

dedicated to the AGCH. To let the MS know about the

configuration information, the system message of every cell

contains a configuration parameter, that is, the access grantreserve blocks (AGBLK).

AGBLK is represented in decimal numerals, and its value range

is:

CCCH is not combined with SDCCH: 0～7.

CCCH is combined with SDCCH: 0～2.

Setting and Impact of AGBLK



2012年4月18日 51

Setting and Impact of AGBLK

The AGBLK setting principle is: given that the AGCH is notoverloaded, try to reduce the parameter as much as possible to

shorten the time when the MS responds to the paging and improve

the quality of service of the system.

The recommended value of AGBLK is usually 1 (when the CCCH iscombined with the SDCCH), 2 or 3 (when the CCCH is not

combined with the SDCCH).

BS-PA-MFRMS



2012年4月18日 52

According to the GSM specifications, every mobile subscriber

belongs to a paging group. In every cell, every paging group

corresponds to a paging subchannel, the MS calculates the

paging group to which it belongs by basing on its own IMSI,

then calculates the location of the paging subchannel belonging

to the paging group. In an actual network, the MS only

"receives“

the contents in the paging subchannel to which itbelongs but ignores the contents in other paging subchannels, or

even turn off the power supply of some hardware equipment of

the MS for other paging subchannels to save the MS power

overhead (i.e. DRX source). The BS-PA-MFRMS refers to how

many multi-frames are used as a cycle of a paging subchannel.This parameter in fact determines how many paging sub-

channels are to be divided from the paging channels of a cell.

BS-PA-MFRMS is represented in decimal numerals



2012年4月18日 53

and its value range is 2～9, its unit is multiframe

（51 frames）, its default value is 2

BS-PA-MFRMS Multiframes of the same paging groupthat cycle on the paging channel

2 2

3 3

4 4

5 5

6 6

7 7

8 8

9 9

Periodic Updating Timer (T3212



2012年4月18日 54

Periodic Updating Timer (T3212）

The reasons for the location update in the GSM system are of

two types: one is that the MS finds its location area changed

(with a different LAC), the other one is that the network requires

the MS to periodically update its location. The frequency of

periodic location update is controlled via the network and the

period length is determined by the parameter T3212.In general, in areas with larger traffic and signaling flow, you

should select the larger T3212（e.g. 16 hours, 20 hours or even

25 hours）, but in areas with smaller traffic and lower signaling

flow, you can set the smallerT3212 (3 hours or 6 hours, etc.). In

areas where traffic is far beyond the system capacity, werecommend that you set T3212 as 0.

NCCPERM(1)



2012年4月18日 55

NCCPERM(1)

In the connection mode (during the conversation), the MS willreport the measured signals of the adjacent cells to the BS, but

each report may contain at most 6 adjacent cells, Therefore, let

the MS only report the information of the cells that may become

the hand-over target cells, do not let the MS report the

information merely according to the signal level withoutselection (usually do not let the MS report other GSMPLMN

cells). The above functions can be fulfilled by limiting the MS

to merely measure the cells whose NCC have been specified.

The NCCPERM lists the NCCs of cells to be measured by the

MS.

NCCPERM(2)



2012年4月18日 56

NCCPERM(2)

In general, each area is allocated with one (or several)NCC. The NCCPERM of each cell in the area should

contain the NCC of the area, otherwise a large number

of cross-cell drop calls will occur and the cell

reselection will fail. To ensure the normal roamingbetween different areas, the border cells of an area

should contain the NCC of its adjacent areas.

RLT



2012年4月18日 57

RLT

During the MS conversation-, when the downward voice (or data)quality is degraded to be unacceptable and cannot be improved

through the RF power control or handover (i.e. the so-called

radio link fault), the MS will either start the call re-connection or

forcedly disconnect the link. As the forced disconnection actually

means a "drop call" process, the MS will regard it as a downwardradio link fault when the communication quality is unacceptable

(usually the user has to hang up). In this case, it is provided in the

GSM specifications that the MS needs a counter S to assign an

initial value--"downward radio link timeout"--. When S is

counted to 0, the MS will report the downward radio link fault.

MBCR 1



2012年4月18日 58

MBCR（1）

In the single band GSM system, when the MS reports the adjacentcell measurement result to the network, it only needs to report the

contents of the 6 adjacent cells with the strongest signals in a band.

When multiple bands form a network, the telecom operator often,

according to the actual situation of the network, wants the MS to

access to a frequency band with priority during the handover, so

the operator hopes that the MS will report the measurement result

on the basis of not only signal strength but signal band as well.

The parameter "multiband indication (MBCR)" is used to notify

the MS that it should report the multiband adjacent cell contents.

The value is 0-3

MBCR 2



2012年4月18日 59

MBCR（2）

0: Based on the signal strength of adjacent cells,the MS reports the measurement results of 6

adjacent cells whose signals are the strongest,

whose NCC are known and allowed no matterin which band the adjacent cells lie.

The default value is “0”

MBCR 3



2012年4月18日 60

MBCR（3）

1: The MS should report the measurement resultof an adjacent cell in each band (not including theband used by the current service area) in theadjacent table, whose signal is the strongest and

whose NCC is already known and allowed. Itshould also report in the rest position the adjacentcells in the band used by the current service area.If there are still rest positions, it will report the

information of the rest adjacent cells no matter inwhich band these adjacent cells lie.

MBCR 4



2012年4月18日 61

MBCR（4）

2: The MS should report the measurement resultsof two adjacent cells in each band (not includingthe band used by the current service area) in theadjacent table, whose signals are the strongest

and whose NCC are already known and allowed.It should also report in the rest position theadjacent cells in the band used by the currentservice area. If there are still rest positions, it will

report the information of the rest adjacent cells nomatter in which band these adjacent cells lie.

MBCR（5）



2012年4月18日 62

3: The MS should report the measurementresults of three adjacent cells in each band (not

including the band used by the current service

area) in the adjacent table, whose signals arethe strongest and whose NCC are already

known and allowed.

8.gsm radio parameter

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