ue behaviors in idle-mode description(2008!05!30)

RAN

UE Behaviors in Idle Mode Description Issue 01

Date 2008-05-30

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ii Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd

Issue 01 (2008-05-30)

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RAN UE Behaviors in Idle Mode Description Contents

Issue 01 (2008-05-30) Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd

i

Contents

1 Change History...........................................................................................................................1-1

2 UE Behaviors in Idle Mode Introduction..............................................................................2-1

3 UE Behaviors in Idle Mode Principles...................................................................................3-1 3.1 PLMN Selection............................................................................................................................................3-2

3.1.1 Automatic PLMN Selection .................................................................................................................3-2 3.1.2 Manual PLMN Selection .....................................................................................................................3-2

3.2 Cell Selection ................................................................................................................................................3-3 3.2.1 Cell Selection Procedure......................................................................................................................3-3 3.2.2 Cell Selection Criteria..........................................................................................................................3-5

3.3 Cell Reselection ............................................................................................................................................3-6 3.3.1 Cell Reselection Process ......................................................................................................................3-6 3.3.2 Measurement Start Criteria ..................................................................................................................3-7 3.3.3 Cell Reselection Criteria ....................................................................................................................3-10

3.4 Location Registration ..................................................................................................................................3-12 3.4.1 Classification of Location Registration..............................................................................................3-13 3.4.2 Normal Location Registration............................................................................................................3-13 3.4.3 Periodic Location Registration...........................................................................................................3-13 3.4.4 IMSI Attach/Detach ...........................................................................................................................3-13

3.5 Paging Reception ........................................................................................................................................3-14 3.5.1 Reception Process ..............................................................................................................................3-14 3.5.2 Reception Technology........................................................................................................................3-14

3.6 System Information Reception....................................................................................................................3-15 3.6.1 Structure of System Information........................................................................................................3-15 3.6.2 Reception of System Information ......................................................................................................3-15

4 Reference Documents ...............................................................................................................4-1

RAN UE Behaviors in Idle Mode Description 1 Change History


1-1

1 Change History

UE behaviors in idle mode Change History provides information on the changes between different document versions.

Document and s

T nt and versions

Product Version

able 1-1 Docume product

Document Version RAN Version RNC Version NodeB Version

01 (2008-05-30) 10.0 V200R010C01B051 V100R010C01B049V200R010C01B040

Draft (2008-03-20) 10.0 V200R010C01B050 V100R010C01B045

specific product version.

Editorial change: refers to the change in the information that was inappropriately bed in the earlier version.

01(2008-05-30) This is the document for the first commercial release of RAN10.0.

C d with draft (2008-03-20) of RAN10.0, issue 01 (2008-05-30) of RANinc ates the changes described in the following table.

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

Feature change: refers to the change in the feature UE behaviors in idle mode of a

described or the addition of the information that was not descri

ompareorpor

10.0

Change Type

Change Description Parameter Change

Feature change

None None

1 Change History RAN

UE Behaviors in Idle Mode Description

1-2 Huawei Proprietary and Confidential Copyright © Huawei Technologies Co., Ltd

Issue 01 (2008-05-30)

Change Change Description Parameter Type Change

Editorial change

General documentation change: None The UE Behaviors in Idle Mode Parameters is removed

au N10.0 parameter reference. The structure is optimized. bec se of the creation of RA

Draft (2008-03-20) This is the draft of the document for first commercial release of RAN10.0.

Compared with issu ing changes: e 03 (2008-01-20) of RAN6.1, this issue makes the follow

Change Type Change Description Parameter Change

Feature change None. None.

The parameter lists are moved to 3.2 UE Behaviors in Idle Mode Parameters and the hyperlinks are made to the corresponding parameter tables.

Editorial change

Implementing information has been moved to a separate document. For information on how to implementing UE behaviors in idle mode, please refer to Configuring UE behaviors in idle mode in RAN Feature Configuration Guide.

None.

RAN UE Behaviors in Idle Mode Description 2 UE Behaviors in Idle Mode Introduction


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2 UE Behaviors in Idle Mode Introduction

The UE enters the idle mode immediately after the switch-on. The feature "UE behaviors in e t the UE is ready to start a service (for example, to make a call or pick

a cal

s that the PLMN selected by the UE provides services properly.

e network. This procedure is es: periodical location registration and the location registration caused ange.

In ad

eception ion to the UE that camps on the cell. Upon

the network information and takes

is s:

the PLMN

Get ready to respond to paging messages Receive cell broadcast services

twork periodically or be triggered by events

Impact p

This feature has impacts on the following aspects:

idl mode" ensures thal).

The behaviors mainly include:

PLMN selection This procedure ensureCell selection and reselection This procedure ensures that the UE finds a suitable cell to camp on. Location registration This procedure is used by the UE to report its status to thmainly of two typby location area ch

dition, the UE in idle mode takes the following actions:

Paging reception The UE detects the paging indicate on the PICH within the predefined time and receives the corresponding paging information on the S_CCPCH. System information rThe network broadcasts the network informatreception of system information, the UE obtains actions accordingly.

Th feature enables the UE to behave as follow

Receive system information from Get ready to establish the RRC connection

Report the UE status to the ne

Im act on System Performance

2 UE Behaviors in Idle Mode Introduction RAN



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The network parameter affects the success rate of service access and paging.

the quality of received signals. affects the UE's access to a cell. When the load is heavy, the UE

ay fail to access the cell.

Impact on Other Features

Network Elements Involved in idle mode.

Table 2-1 NEs involved in the fe behaviors in idle mode

The network parameter affects the power consumption of the UE in idle mode. The capability of the UE affects

The load of the networkm

None.

Table 2-1 describes the NEs involved in the feature UE behaviors

ature UE

UE NodeB RNC MSC Server

MGW SGSN GGSN HLR

√ √ – – – – – √

–: not involved √: involved

UCenter

E = User Equipment, RNC = Radio Network Controller, MSC Server = Mobile Service Switching Server, MGW = Media Gateway, SGSN = Serving GPRS Support Node, GGSN = Gateway GPRS

Support Node, HLR = Home Location Register

RAN UE Behaviors in Idle Mode Description 3 UE Behaviors in Idle Mode Principles


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3 UE Behaviors in Idle Mode Principles

About Thi

T ts the conten

s Chapter

he following table lis ts of this chapter.

Section Describes

3.1 PLMN Selection At switch-on, or following recovery from lack of coverage, or selecting a cell that belongs to other PLMNs, the UE will select a PLMN. The PLMN selection procedure is used for finding a suitable PLMN.

3.2 Cell Selection When the PLMN is selected and the UE is in idle mode, the UE starts to select a cell that belongs to the selected PLMN to camp on and to obtain normal services.

3.3 Cell Reselection ighboring

needs to select the most suitable cell to camp on. This

The signal strength of both serving cell and necells varies with the movement of a UE and so the UE

process is called cell reselection. The cell reselection involves three parts: cell reselection process, measurement start criteria, and cell reselection criteria.

3.4 Location Registration Location registration is used for the PLMN to trace the t t

current status of the UE. Location registration ensures thathe UE is connected to the network when the UE does noperform any operation for a long period.

3.5 Paging Reception By receiving paging messages, the UE is notified of the service requests made by the CN and the changes in system information.

3.6 System Information Reception

Upon reception of system information, the UE obtains the network information and takes actions accordingly.

3 UE Behaviors in Idle Mode Principles RAN



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3.1 PLMN Selection At switch-on, or following recovery from lack of coverage, or selecting a cell that belongs to other PLMNs, the UE will select a PLMN. The PLMN selection procedure is used for finding a suitable PLMN.

There are two modes of PLMN selection:

Automatic selection The UE automatically selects a PLMN according to the priority order.

Manual selection The UE shows all available PLMNs to the subscriber. The subscriber then selects a PLMN.

3.1.1 Automatic PLMN Selection In automatic PLMN selection mode, the UE can select a PLMN from the Home PLMNs (HPLMNs) and roam in the Visited PLMN (VPLMN).

The MCC and MNC in the PLMN identity of the HPLMN match the MCC and MNC in the IMSI of

the UE. The PLMNs, except the HPLMNs, which the UE camps on, are defined as VPLMNs.

Selecting from the HPLMN

To select a PLMN from the HPLMNs, the UE does as follows:

The UE maintains a list of allowed and available PLMNs in priority order. When selecting a PLMN, the UE searches for the PLMNs from the highest priority to the lowest.

Roaming in the VPLMN

If a UE stays in a VPLMN, it regularly searches for the HPLMN and higher-priority PLMNs for better services.

For this purpose, a value of T minutes may be stored in the SIM. Either T is in the range 6 minutes to 8 hours in 6-minute steps or T indicates that no periodic attempts shall be made. If no value is stored in the SIM, a default value of 60 minutes is used.

When the UE attempts to access the HPLMN or the PLMN with higher priority, the UE must adhere to the following rules:

After the UE is switched on, a period of at least two minutes and at most T minutes shall elapse before the first attempt is made.

Periodic attempts shall be performed only by the UE in idle mode. Only the priority levels of equivalent PLMNs of the same country (which serve as the

current serving VPLMN) can be compared with the priority level of a selected PLMN.

3.1.2 Manual PLMN Selection To manually select a PLMN, the UE does as follows:

The UE maintains a list of allowed and available PLMNs in priority order. When selecting a PLMN, the UE indicates the list to the subscriber who will select a PLMN, and then camps on the selected PLMN.



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For more details of the PLMN selection, refer to 3GPP TS 25.304 and 3GPP TS 23.122.

3.2 Cell Selection When the PLMN is selected and the UE is in idle mode, the UE starts to select a cell that belongs to the selected PLMN to camp on and to obtain normal services.

3.2.1 Cell Selection Procedure Figure 3-1 shows the cell selection procedure for the UE in idle mode.




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Figure 3-1 Cell selection procedure for the UE in idle mode

To select a new PLMN, go back to position 1 of the procedure.

Table 3-1 describes the states involved in the cell selection.



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Table 3-1 UE states involved in the cell selection

SN State Description

1 Camped normally

The UE obtains normal services.

2 Connected mode

After RRC connection setup, the UE changes from the idle mode to the connected mode (CELL_DCH, CELL_FACH, CELL_PCH, or URA_PCH state)

3 Any cell selection

The UE attempts to find an acceptable cell of any PLMN to camp on.

4 Camped on any cell

The UE obtains limited services and selects a cell through cell selection or reselection. In this case, the PLMN identity is not considered.

Figure 3-1 also shows the following items:

Initial cell selection If no cell information is stored for the PLMN, the UE starts the initial cell selection. For this procedure, the UE need not know in advance which Radio Frequency (RF) channels are UTRA bearers. The UE scans all RF channels in the UTRA band according to its capabilities to find a suitable cell of the selected PLMN. On each carrier, the UE need only search for the strongest cell. Once a suitable cell is found, this cell shall be selected.

Stored information cell selection For this procedure, the UE need know the central frequency information and other optional cell parameters that are obtained from the measurement control information received before, such as scrambling codes. After this procedure is started, the UE selects a suitable cell if any. Otherwise, the initial cell selection procedure is triggered.

Suitable cell A suitable cell is the cell that the UE may camp on to obtain normal services.

Cell selection of the UE leaving connected mode When returning to the idle mode from the connected mode, the UE shall select a suitable cell to camp on. Candidate cells for this selection are the cells used immediately before the UE leaves the connected mode. When returning to the idle mode after an emergency call on any PLMN, the UE shall select an acceptable cell to camp on. Candidate cells for this selection are the cells used immediately before the UE leaves the connected mode. If no acceptable cell is found, the UE shall continue to search for an acceptable cell of any PLMN in the state "Any cell selection".

Acceptable cell An acceptable cell is the cell that the UE may camp on to obtain limited services. For example, the UE may originate emergency calls.

3.2.2 Cell Selection Criteria The cell selection criterion S is fulfilled when:

Srxlev > 0 and Squal > 0




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where

Squal = Qqualmeas – Qqualmin Srxlev = Qrxlevmeas - Qrxlevmin - Pcompensation

Parameter Description

Squal Cell selection quality value (dB) Applicable only to FDD cells

Srxlev Cell selection RX level value (dBm)

Qqualmeas Measured cell quality value Quality of the received signal indicated in average CPICH Ec/N0 (dB) for FDD cells Applicable only to FDD cells

Qrxlevmeas Measured cell RX level value CPICH RSCP of received signal for FDD cells (dBm) and P-CCPCH RSCP of received signal for TDD cells (dBm)

Qqualmin Min quality level

Qrxlevmin Min RX level

Pcompensation Max (UE_TXPWR_MAX_RACH – P_MAX, 0) (dB) where UE_TXPWR_MAX_RACH: Max allowed UE UL TX power. P_MAX: maximum RF output power of the UE (dBm)

3.3 Cell Reselection The signal strength of both serving cell and neighboring cells varies with the movement of a UE and so the UE needs to select the most suitable cell to camp on. This process is called cell reselection. The cell reselection involves three parts: cell reselection process, measurement start criteria, and cell reselection criteria.

3.3.1 Cell Reselection Process The cell reselection process is as follows:

Step 1 The UE calculates the cell SX according to the following formulas:

Squal = Qqualmeas - Qqualmin Srxlev = Qrxlevmeas - Qrxlevmin - Pcompensation



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For detailed description of the formulas, see 3.2 Cell Selection. Figure 3-1 in Cell Selection shows the cell reselection of the UEs in idle mode.

Step 2 The UE decides whether to start the intra-frequency or inter-frequency measurement according to the measurement start criteria.

To start the intra-frequency, inter-frequency, or inter-RAT measurement, go to Step 3. Otherwise, end the cell reselection.

Step 3 The cells are queued according to the measurement results.

Step 4 The UE selects a suitable cell to camp on according to the cell reselection criteria.

3.3.2 Measurement Start Criteria The Hierarchical Cell Structure (HCS) may affect the measurement start criteria for cell reselection.

HCS Disabled

Figure 3-2 shows the intra-frequency, inter-frequency, and inter-RAT measurement criteria in the case when the system messages broadcast by the serving cell indicate that the HCS is disabled.

Figure 3-2 Measurement start criteria for cell reselection with HCS disabled

Intra-frequency measurement − If Squal > Sintrasearch, the UE need not start the intra-frequency measurement. − If Squal ≤ Sintrasearch, the UE need start the intra-frequency measurement. − If system messages do not contain Sintrasearch, the UE always need start the

intra-frequency measurement. Sintrasearch is set through Intra-freq cell reselection threshold for idle mode on the RNC side.

Inter-frequency measurement − If Squal > Sintersearch, the UE need not start the inter-frequency measurement. − If Squal ≤ Sintersearch, the UE need start the inter-frequency measurement.




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− If system messages do not contain Sintersearch, the UE always need start the inter-frequency measurement.

Sintersearch is set through Inter-freq cell reselection threshold for idle mode on the RNC side.

Inter-RAT measurement − If Squal > SsearchRATm, the UE need not start the inter-RAT measurement. − If Squal ≤ SsearchRATm, the UE need start the inter-RAT measurement. − If system messages do not contain SsearchRATm, the UE always need start the inter-RAT

measurement. SsearchRATm is set through Inter-RAT cell reselection threshold on the RNC side.

HCS Enabled

When the HCS is enabled, the measurement criteria for the UE in movement are listed in Table 3-2, Table 3-3, Table 3-4, and Table 3-5.

Intra-frequency and inter-frequency measurement criteria for the UE in slow movement

Table 3-2 Intra-frequency and inter-frequency measurement criteria for the UE in slow movement

Condition Result

Srxlev ≤ SsearchHCS or Squal ≤ Sintersearch

All intra-frequency and inter-frequency cells are measured.

Squal ≤ Sintrasearch Intra-frequency and inter-frequency cells are measured with their HCS level no lower than that of the current cell.

Squal > Sintrasearch Intra-frequency and inter-frequency cells are measured with their HCS level higher than that of the current cell.

Sintrasearch not delivered All intra-frequency cells are measured. Inter-frequency cells are measured with their HCS level higher than that of the current cell.

SsearchHCS or Sintersearch not delivered


SsearchHCS is set through HCS cell reselection threshold on the RNC side. The HCS of intra-frequency neighboring cells of a cell is usually consistent with that of the cell. If the Squal of the current cell is good enough, that is, Squal > Sintrasearch, the UE only needs to compare the Squal in these cells with different HCSs.

Intra-frequency and inter-frequency measurement criteria for the UE in fast movement



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Table 3-3 Intra-frequency and inter-frequency measurement criteria for the UE in fast movement

Condition Result

Srxlev ≤ SsearchHCS or Squal ≤ Sintersearch


SsearchHCS or Sintersearch not delivered


Others such as Srxlev and Squal are good.

All intra-frequency and inter-frequency cells are measured with their HCS level no higher than that of the current cell.

Inter-RAT measurement criteria for UE in slow movement

Table 3-4 Inter-RAT measurement criteria for the UE in slow movement

Condition Result

Srxlev ≤ SHCS,RATm or Squal ≤ SSearchRATm

Inter-RAT cells are measured.

Squal ≤ Slimit,SearchRATm Inter-RAT cells are measured when the HCS level of inter-RAT cells is higher than or equal to that of the current cell.

Squal > Slimit,SearchRATm The UE need not measure inter-RAT cells.

SHCS,RATm not delivered Inter-RAT cells are measured.

SHCS,RATm is set through HCS inter-rat reselection threshold on the RNC side. Slimit,SearchRATm is set through HCS search inter-rat limit threshold on the RNC side.

Inter-RAT measurement criteria for the UE in fast movement

Table 3-5 Inter-RAT measurement criteria for the UE in fast movement

Condition Result

Srxlev ≤ SHCS,RATm or Squal ≤ SSearchRATm


SHCS,RATm or SSearchRATm not delivered


Others such as Srxlev and Squal are good.

All inter-RAT cells are measured when the HCS level of inter-RAT cells is lower than or equal to that of the current cell.




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3.3.3 Cell Reselection Criteria H criteria and R criteria are used for cell reselection.

The quality level threshold criterion H for the HCS is used to determine whether the prioritized ranking based on the hierarchical cell reselection rules shall apply. The criterion is defined by:

If the system information indicates that the HCS is not used, the quality level threshold criterion H does not apply.

The cell-ranking criterion R is defined by:

where

TEMP_OFFSETn is used as an offset to the R criteria for the duration of PENALTY_TIMEn after a timer Tn is started for that neighboring cell.

TEMP_OFFSETn and PENALTY_TIMEn are only applicable when the system information indicates that the HCS is enabled.

The mapping between the parameters in the previous formulas and the parameters in the LMT are described in Table 3-6.

Table 3-6 Mapping between the parameters in formulas and the parameters in the LMT T

Parameters in Criteria Parameter ID Parameter Name

Qhcss

Qhcsn

Qhcs Quality threshold for HCS reselection

IdleQhyst1s Hysteresis 1 for idle modeQhysts

IdleQhyst2s Hysteresis 2 for idle mode

TempOffset1 HCS Cell Reselect TempOffset1TEMP_OFFSETn

TempOffset2 HCS Cell Reselect TempOffset2



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PENALTY_TIMEn TpenaltyHcsReselect

HCS Cell Reselect Penalty Timer

Figure 3-3 shows the cell reselection procedure, which describes the measurement start and criteria relations. The actual procedure varies with UE implementation.

Figure 3-3 Cell reselection procedure

Firstly, the UE shall select certain cells that fulfill the S criterion to rank in the following cases:

When HCS is not used (UseOfHcs is set to NOT_USED), the UE shall rank all cells, not considering HCS priority levels.

When HCS is used (UseOfHcs is set to USED) and UE is in low mobility, the UE shall rank all cells that have the highest HCSPrio among those cells that fulfill the criterion H ≥ 0.




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When HCS is used and UE is in high mobility and if there are cells with a lower HCS priority than the serving cell that fulfil the criterion H >= 0, the UE shall rank all cells that have the highest HCSPrio among those cells that fulfil the criterion H >=0 and have a lower HCS priority than the serving cell.

When HCS is used and UE is in high mobility and if there are cells that fulfil the criterion H >= 0 with an HCS priority higher or equal to the HCS priority of the serving cell, the UE shall rank all cells that have the lowest HCSPrio that fulfil the criterion H >= 0 and have an HCS priority higher or equal to the HCS priority of the serving cell.

When HCS is used and if no cell fulfills the criterion H ≥ 0, the UE shall rank all cells, not considering HCS priority levels.

Secondly, the UE shall rank the cells according to the R criteria, deriving Qmeas,n and Qmeas,s and calculating the R values, as described in the cases below.

The offset IdleQoffset1sn is used for Qoffsets,n to calculate Rn. The hysteresis IdleQhyst1s is used for Qhysts to calculate Rs.

If HCS is enabled, TempOffset1 is used for TEMP_OFFSETn to calculate TOn. Otherwise, TEMP_OFFSETn is not used to calculate Rn. The best ranked cell is the cell with the highest R value.

If a TDD or GSM cell is ranked as the best cell, the UE shall reselect that TDD or GSM cell.

If an FDD cell is ranked as the best cell and the quality measure for cell selection and reselection is set to CPICH RSCP(QualMeas = CPICH_RSCP), the UE shall reselect that FDD cell.

If an FDD cell is ranked as the best cell and the quality measure for cell selection and reselection is set to CPICH Ec/N0(QualMeas = CPICH_ECNO), the UE shall perform a second ranking of the FDD cells according to the R criteria specified above.

In this case, however, the UE uses the measurement quantity CPICH Ec/N0 for deriving the Qmeas,n and Qmeas,s, and then calculating the R values of the FDD cells. The offset IdleQoffset2sn is used for Qoffsets,n to calculate Rn, and the hysteresis IdleQhyst2s is used for Qhysts to calculate Rs.

If the system information indicates that the HCS is enabled, TempOffset2 is used to calculate TOn. Otherwise, TEMP_OFFSETn is not used to calculate Rn. Following the second ranking, the UE shall reselect the best ranked FDD cell.

In all the previous cases, the UE can reselect a new cell only when the following conditions are met:

The new cell is better ranked than the serving cell during a time interval Treselections . More than one second has elapsed since the UE camped on the current serving cell.

For details of the cell reselection criteria, refer to 3GPP TS 25.304.

3.4 Location Registration Location registration is used for the PLMN to trace the current status of the UE. Location registration ensures that the UE is connected to the network when the UE does not perform any operation for a long period.



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3.4.1 Classification of Location Registration Location registration refers to the location update for non-GPRS and the route update for GPRS. Location registration is of the following three types:

Normal location registration Periodic location registration IMSI attach/detach

For the procedure of location registration, refer to Location Update Procedure.

3.4.2 Normal Location Registration The UE performs normal location registration in the following conditions:

After the switch-on, the UE selects a suitable cell that belongs to a new LA or RA. That is, the LA or RA is different from that recorded in the USIM before the switch-off of the UE.

The UE in idle mode enters the cell of a new LA or RA.

3.4.3 Periodic Location Registration Periodic location registration may be used to periodically notify the network of the availability of the UE.

It is controlled by a Periodic Location Update timer (T3212, for non-GPRS operation) or a Periodic Routing Area Update timer (T3312, for GPRS operation). The value of T3212 is sent by the network to the UE in SIB 1. The value of T3312 is sent by the network to the UE in the messages ATTACH ACCEPT and ROUTING AREA UPDATE ACCEPT. The value of T3312 shall be unique within an RA.

T3212 is set through Periodical location update timer on the RNC side. T3312 is set on the CN side.

The timer T3212 is described as follows:

When the UE is switched on or the system information indicates that periodic location registration shall be applied, and the timer T3212 is not running. Then, the timer shall be loaded with a random value between 0 and the value of T3212, and shall be started.

When the timer T3212 reaches its expiry value, the UE shall initiate the periodic location registration.

The timer T3212 shall be prevented from triggering periodic location update in connected mode. When the UE returns to the idle mode, T3212 shall be initiated with respect to the broadcast timeout value and then be started.

If the UE performs a successful combined routing area update, the timer T3212 shall be prevented from triggering the periodic location update until the UE starts location update, for example, because a network operation mode changes or the UE uses non-GPRS services only.

3.4.4 IMSI Attach/Detach The IMSI attach/detach process facilitates the fast location registration of the UE in specific conditions.




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When the IMSI attach/detach operation applies, the UE shall send the IMSI detach message to the network when the UE is switched off or the SIM is removed while being in the UPDATED state. This IMSI detach message will not be acknowledged by the network.

The system information will contain an indicator indicating whether the IMSI attach/detach operation is mandatory in the cell. The UE shall operate in accordance with the received value of the indicator. This indicator, however, shall not be considered in GRPS attach/detach.

If the UE still stays in the same LA or RA after being switched on again, the UE shall perform an LR request indicating IMSI attach. Otherwise, the UE shall perform an LR request indicating normal location update.

You can set IMSI attach/detach indicator by set Attach/detach indication.

3.5 Paging Reception By receiving paging messages, the UE is notified of the service requests made by the CN and the changes in system information.

3.5.1 Reception Process When a UE stays in idle mode, the paging to the UE is performed within an LA or RA or the whole RNC. The UE reads the paging information from the PICH and S-CCPCH. The PICH indicates when the UE reads the paging information from the S-CCPCH, whereas the S-CCPCH carries specific paging messages.

3.5.2 Reception Technology To reduce power consumption, the UE can read the information from the PICH only at a particular time. This is known as the Discontinuous Reception (DRX) technology. The interval between two consecutive periods of time is called DRX cycle.

For Frequency Division Duplex (FDD), the DRX cycle length shall be 2k frames, where k is an integer and is decided by the following three parameters:

CN domain specific DRX cycle length for CS CN domain specific DRX cycle length for PS UTRAN DRX cycle length coefficient

The parameters are described as follows:

CN domain specific DRX cycle lengths The UE may be attached to different CN domains with different CN domain specific DRX cycle lengths. The UE shall store these lengths for all CN domains where the UE is attached and shall use the shortest one. The value is set through DRX cycle length coefficient on the RNC side.

UTRAN DRX cycle length This parameter value is sent to the UE through the RRC CONNECTION SETUP message without distinguishing specific CN domain types. For a UE in idle mode, the DRX cycle length equals the shortest value of the stored DRX cycle length for the CN domains where the UE is attached, with no signaling connection established.



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For a UE in CELL_PCH state or URA_PCH state, the DRX cycle length equals the shortest value of the following lengths: − UTRAN DRX cycle length − Any of the stored DRX cycle length for the CN domains where the UE is attached,

with no signaling connection established

If you set a big DRX cycle length coefficient, the period for UE detect paging info will be long; therefore, the UE can reduce the power consumption. However, the delay for responding to a paging will be long.

3.6 System Information Reception Upon reception of system information, the UE obtains the network information and takes actions accordingly.

3.6.1 Structure of System Information The structure of system information is like a tree, which includes the following items:

MIB Master Information Block (MIB) provides reference and scheduling information for a number of SIBs in a cell or one or two Scheduling Blocks (SBs) in a cell. The MIB contains only the PLMN types supported and the corresponding PLMN identities.

SB Scheduling Block (SB) provides reference and scheduling information for other SIBs. The scheduling information of an SIB may be included in the MIB or SB.

SIB System Information Block (SIB) contains actual system information. It consists of system information elements (IEs) with the same purpose.

When selecting a new cell, the UE reads the MIB. The UE may locate the MIB through the predefined scheduling information.

The UE may use the scheduling information in the MIB and SB to locate each SIB to be acquired. If the UE receives an SIB in a position according to the scheduling information and considers the content as valid, the UE will read and store the SIB.

3.6.2 Reception of System Information The UE shall read system information broadcast on a BCH transport channel when the UE is in idle mode or connected mode (CELL_FACH, CELL_PCH, or URA_PCH state). Then, the UE takes actions on the following occasions:

When the UE is switched off Except the SIBs stored in the USIM and used for the stored information cell selection, the UE shall consider other stored SIBs as invalid.

When the UE is switched on The UE shall store SIBs with an area scope (cell, PLMN, or equivalent PLMN) and their value tag. These SIBs are used when the UE returns to the cells.

When the UE selects a new cell in a new PLMN




Issue 01 (2008-05-30)

The UE shall consider all current SIBs with an area scope (cell or PLMN) as invalid, and shall store and use a new SIB. If the identity of this PLMN is not equivalent to the identity of the previously selected PLMN, the UE shall consider all SIBs with an area scope (equivalent PLMN) as invalid.

When the UE selects a new cell in the current PLMN

The UE shall consider all current SIBs with an area scope (cell) as invalid, and shall store and use a new SIB.

RAN UE Behaviors in Idle Mode Description 4 Reference Documents


4-1

4 Reference Documents

Th describes the reference documents related to UE behaviors in idle mode.

3GPP, TS

is

22.011 "Service accessibility"

ification; Core Network Protocols -

es for Cell Reselection in Connected Mode"

3GPP, TS 25.331 "Radio Resource Control (RRC)" 3GPP, TS 31.102 "Characteristics of the USIM Application"

3GPP, TS 23.122 "NAS Functions related to Mobile Station (MS) in idle mode" 3GPP, TS 24.008 "Mobile radio interface layer 3 specStage 3"

3GPP, TS 25.304 "UE Procedures in Idle Mode and Procedur