ZTE UMTS Idle Mode and Channel Behavior Feature Guide U9.2

8/10/2019 ZTE UMTS Idle Mode and Channel Behavior Feature Guide U9.2

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Idle Mode and Common Channel Behavior Feature Guide

ZTE Confidential Proprietary 2010 ZTE Corporation. All rights reserved. I

Idle Mode and Common Channel Behavior Feature

Guide

Version Date Author Approved By Remarks

V4.0 2010-06-18Wang

KunhuangCui LiLi Not open to the Third Party

2010 ZTE Corporation. All rights reserved.

ZTE CONFIDENTIAL:This document contains proprietary information of ZTE and is not to bedisclosed or used without the prior written permission of ZTE.

Due to update and improvement of ZTE products and technologies, information in this document

is subjected to change without notice.


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ZTE Confidential Proprietary 2010 ZTE Corporation. All rights reserved. II

TABLE OF CONTENTS

1

Functional Attribute ............................................................................................1

2

Overview .............................................................................................................1

2.1

Function Introduction ............................................................................................1

2.1.1 PLMN Selection ...................................................................................................1

2.1.2 Cell Selection and Reselection ..............................................................................12.1.3 Location Area Update ...........................................................................................12.1.4

Routing Area Update ............................................................................................2

2.1.5 URA Update ........................................................................................................22.1.6 Cell Update..........................................................................................................32.1.7 Random Access Process of PRACH......................................................................3

3 Technical Description .........................................................................................4

3.1

Strategy of PLMN Selection ..................................................................................43.1.1

Support for PLMN Selection ..................................................................................4

3.1.2

PLMN Selection at Switch-on ........ ........ ........ ........ ........ ........ ........ ........ ........ ........5

3.1.3 Automatic PLMN Selection Mode ....... .... .... .... ... .... .... ... .... ... .... .... ... .... ... .... ... .... ... ..53.1.4 Manual PLMN Selection Mode ..............................................................................7

3.1.5 Roaming ..............................................................................................................73.2 Strategy of Cell Selection and Reselection ......... ........ ........ ....... ......... ........ ......... ...73.2.1

States and State Transitions in Idle Mode ..............................................................8

3.2.2

Cell Selection Process ........................................................................................11

3.2.3 Camped Normally State......................................................................................123.2.4 Rules of Cell Reselection Measurement...............................................................13

3.2.5 Cell Selection When Leaving Connected Mode ....................................................253.2.6 Any Cell Selection State .. .... ... .... ... .... ... .... ... ... .... .... .... ... .... ... .... ... ... .... .... .... ... .... .25

3.2.7

Camped on Any Cell State ......... ........ ......... ....... ........ ........ ......... ...... ......... ........ .253.2.8

Cell Reservations and Access Restrictions ..........................................................26

3.2.9 Cell Reselection Process in RRC Connected Mode ..............................................283.2.10 Parameters and Configuration for Cell Selection and Reselection......... ......... ........28

3.2.11 SIB11bis usage ..................................................................................................283.3 Strategy of LA and RA Update ............................................................................29 3.3.1

LA and RA Structure...........................................................................................29

3.3.2

Normal LA and RA Updating ...............................................................................29

3.3.3 Periodic LA and RA Updating..............................................................................29 3.3.4 IMSI Attach/Detach ............................................................................................30

3.4 Strategy of URA Update .....................................................................................303.4.1 Process of URA Update......................................................................................303.5 Strategy of CELL Update ....................................................................................31

3.5.1

Process of CELL Update ....................................................................................32

3.6 Random Access Process of PRACH....................................................................333.6.1 PRACH Structure ...............................................................................................33

3.6.2 Preamble Part ....................................................................................................333.6.3

Message Part.....................................................................................................33

3.6.4 Random Access Process of Physical Layer..........................................................36

3.6.5

Random Access Process of the MAC Layer ........ ........ ......... ....... ........ ........ .........40

4 Parameters and Configuration ..........................................................................424.1 Cell Selection/Reselection-related Parameters .....................................................42

4.1.1 Parameter List ...................................................................................................424.1.2 Parameter Configuration ........ ........ ......... ....... ........ ........ ......... ....... ........ ........ .....46 4.2

PRACH-related Parameters ................................................................................85


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ZTE Confidential Proprietary 2010 ZTE Corporation. All rights reserved. III

4.2.1 Parameter List ...................................................................................................854.2.2 Parameter Configuration ........ ........ ......... ....... ........ ........ ......... ....... ........ ........ .....86

5

Glossary ...........................................................................................................97


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ZTE Confidential Proprietary 2010 ZTE Corporation. All rights reserved. IV

FIGURES

Figure 1

UE Registers upon Switch-on or Re-registers a fter Leaving Connected Mode ........ ....4

Figure 2 PLMN Selection-Automatic Mode ............................................................................6

Figure 3 Idle Mode Cell Selection and Reselection ................................................................8

Figure 4 URA update procedure, basic flow.........................................................................30

Figure 5

URA update procedure, failure case ......................................................................31

Figure 6 Cell update procedure, basic flow ........ ........ ........ ........ ........ ........ ........ ........ ........ ..32

Figure 7 Cell update procedure with physical channel reconfiguration ......... ........ ........ ....... ...32

Figure 8

Cell update procedure with radio bearer reconfiguration..........................................32

Figure 9 PRACH Structure .................................................................................................33

Figure 10 Structure of PRACH Message ...............................................................................33

Figure 11

Mapping Relation of PRACH-related Parameters ...................................................35

Figure 12

Relation between the PRACH Access Slot and DL AICH ........................................38

Figure 13 Timing Relation between PRACH and AICH as Observed from the UE Side ........... .39

TABLES

Table 1 Number of Bits Carried in PRACH Message vs. Spectrum Spreading Factor ........ ....35

Table 2

Mapping Relation Between Available UL Access Slot and RACH ........ ......... ........ ...38

Table 3 ASCi-to-Pi Mapping Relation .................................................................................41

Table 4 AC-to-ASC Mapping Relation .... .... .... .... ... .... ... .... ... .... ... .... .... ... .... ... .... ... .... .... ... ....42


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ZTE Confidential Proprietary 2010 ZTE Corporation. All rights reserved. 1

1 Functional Attribute

System version: [RNC V3.09, OMMR V3.09, Node B V4.09, OMMB V4.09]

Property: [Optional]

Related Network Element:

UE NodeB RNC MSCS MGW SGSN GGSN HLR

- - - - -

Note:

*-: not involved.

*: involved.

Dependent Function: [None]

Remarks: [None]

Remarks: [None]

2 Overview

2.1 Function IntroductionThis article introduces the strategies of PLMN selection, cell selection/reselection,

location area update, routing area update, URA update and cell update, as well as therandom access process of PRACH.

2.1.1 PLMN Selection

The UE will select a PLMN when it registers at power-on or re-registers in out of serviceconditions. In addition, the UE can make periodic PLMN selection.

2.1.2 Cell Selection and Reselection

The UE will select an initial cell at power-on or in out of service conditions.

When the UE moves in the IDLE mode, in state URA_PCH or CELL_FACH, it needs tochange the cell that it camps on through the cell reselection strategy.

2.1.3 Location Area Update

The location area (LA) refers to a range where the mobile station can move freelywithout update of VLR. The location area identity (LAI) is made up of MCC+MNC+LAC.


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Besides, the UE in state URA_PCH will trigger the periodic URA update with the reasonof periodic URA update if the preceding LA update condition is not satisfied but thefollowing conditions are satisfied.

The timer T305 in the IE UE Timers and constants in connected mode" set to anyother value than " is set to non infinityand T305 expires.

If the UE does not support HS-DSCH reception but receives the IE "HS-DSCH

paging system information", the IE is not saved currently, and also the 12-bit MSBs

(high 12 bits) of U_RNTI in "SRNC does not equal to the 12-bit MSBs of "Cell

identity" in SIB3.

2.1.6 Cell Update

The Cell update means that the UE notifies the RAN of the UE location on a cell level.

The UE will trigger the cell update in the following cases:

Reselection of cell in state CELL_FACH

Radio link failure in state CELL_DCH

T305 periodic cell update.

In state CELL_FACH, the UE returns from the uncovered area to the covered area

and performs periodic cell update.

In state URA_PCH, the UE transmits data on uplink

In state URA_PCH, paging is responded.

In state URA_PCH/CELL_FACH, MBMS p-t-p RB request is sent.

The UE is in paging URA_PCH state on the network side (can be originated by the

UTRAN or CN)

The UE in state CELL_FACH/CELL_DCH detects the RLC unrecoverable error

of theAM RLC entity.

MBMS Counting in state URA_PCH/CELL_FACH

2.1.7 Random Access Process of PRACH

PRACH is the access channel for the UE to originate a call. It includes two parts: the

physical layer random access process and MAC layer random access process.


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3 Technical Description

Figure 1 shows the flow that the UE registers upon switch-on or re-registers after leaving

connected mode. Processes involved are: PLMN selection, cell selection and reselection,LA registration and update and RA registration and update.

Figure 1 UE Registers upon Switch-on or Re-registers after Leaving Connected Mode

In addition, the UE supports periodic LA and RA update to notify the network of the real-time camping information. In state URA_PCH/CELL_FACH, the UE triggers URA/CELLupdate for a service reason. In cases of service setup, the paging process and PRACH

random access process are needed. The processes are introduced in this chapter.

3.1 Strategy of PLMN Selection

The UE maintains a list of allowed PLMN types (SIM/USIM information). The allowed

PLMN type can be GSM-MAP only, ANSI-41 only or both. During PLMN selection andreselection, based on the list of allowed PLMN types and a list of PLMN identities inpriority order, the particular PLMN may be selected either automatically or manually .

Each PLMN in the list of PLMN identities can be identified by either PLMN identity(GSM-MAP) or SID(ANSI-41). In the system information on the broadcast channel, theUE can receive several PLMN identities: a PLMN identity(GSM-MAP) or a SIDor a'PLMN identity ' (GSM-MAP) and a 'SID', in a given cell.

The result of the PLMN selection is an identifier of the selected PLMN, the choice beingbased on the allowed PLMN types, UE capability or other factors.

3.1.1 Support for PLMN Selection

The UE will select a PLMN when it registers at power-on or re-registers after leavingconnected mode. In addition, the UE can make periodic PLMN selection.

The PLMN selection is originated at a NAS. On request of the NAS, the AS searches foravailable PLMN and reports the result to the NAS. The NAS based on the information


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reported by the AS and the allowed PLMN information in SIM/USIM determines whichPLMN will be selected finally.

The UE scans all RF channels in the UTRA/GSM bands according to its capabilities to

find available PLMNs. On each carrier, the UE shall search for the strongest cell andread its system information, in order to find out which PLMN the cell belongs to. If theUE can read one or several PLMN identities in the strongest cell, each found PLMN will

be reported to the NAS as a high quality PLMN, provided that the following high qualitycriterion is fulfilled.

1 For an FDD cell, the measured primary CPICH RSCP value is greater than or equal

to -95 dBm.

2 For an TDD cell,the measured primary CCPCH RSCP value is greater than or equalto -84dBm.

Found PLMNs that do not satisfy the high quality criterion, but for which the UE has

been able to read the PLMN identities are reported to the NAS as other PLMNs in orderof decreasing CPICH RSCP for UTRA FDD cells, or in order of decreasing P-CCPCH

RSCP for UTRA TDD cells.

The search for PLMNs on the carriers may be stopped on request of the NAS. The UEmay optimize this search by using stored information of carrier frequencies and

optionally also information on cell parameters, e.g. scrambling codes, from previouslyreceived measurement control information elements.

Once the UE has selected a PLMN, the cell selection procedure will be performed in

order to select a suitable cell of that PLMN to camp on.

3.1.2 PLMN Selection at Switch-on

Whenever a UE is switched on or re-registers after leaving connected mode, it attempts

to camp on the last registered PLMN or equivalent PLMN, if available. To speed up thePLMN selection procedure, the UE first tries the stored information cell selectionprocedure (refer to 3.2.2.2 Stored Information cell selection), and read systeminformation of corresponding cell to obtain the PLMN ID (PLMN ID comprises MCC andMNC). Then the UE decides whether the chosen cell is acceptable or whether at leastone acceptable cell belonging to that PLMN exists. If the decision is that the PLMN is

available, the UE attempts registration on the PLMN. If the last registered PLMN isunavailable, the process of PLMN registration with stored information is finished andautomatic or manual PLMN selection will be attempted.

If there is no registered PLMN stored in the USIM, the UE selects and attemptsregistration on other PLMNs using either the Automatic mode or the Manual mode.

3.1.3 Automatic PLMN Selection Mode

The Automatic PLMN selection mode is described in Figure 2 In Automatic mode, if nolast registered PLMN exists or is available, the UE will select a PLMN that is availableand allowed, in the following order:

1 Home PLMN (HPLMN), if not previously selected, according to the Radio AccessTechnologies (RATs) supported by the UE.


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2 Each PLMN in the user-controlled PLMNs list in the USIM, if present, in order ofpriority, according to the RATs supported by the UE.

3 Each PLMN in the operator -controlled PLMNs list in the USIM, in order of priority,

according to the RATs supported by the UE.

4 Other PLMNs, according to the high -quality criterion, in random order.

5 Other PLMNs that do not fulfill high-quality criterion, in order of decreasing signal

strength (SS).

PLMNs are considered high quality if the Received Signal Strength Code Power (RSCP)on the PCPICH fulfills the high-quality criterion (for FDD, the PCPICH RSCP level is

greater than or equal to 95 dBm and for GSM, the signal level is above -85 dBm).

A PLMN with at least one acceptable cell is considered available. If that PLMN isallowed, the UE tries to register on it. If registration is successful, the UE displays the

selected PLMN.

When the UE cannot register on any PLMN in the user and operator lists, it attempts toregister on other PLMNs according to the high -quality criterion.

If the UE cannot register on any PLMN, it selects an available PLMN and enters alimited service state. If it does not find an available PLMN, the UE enters the non-servicestate, and waits until a new PLMN is available and allowed.

Figure 2 PLMN Selection-Automatic Mode


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3.1.4 Manual PLMN Selection Mode

The Manual mode allows the user to select a PLMN among those indicated by the UE.The UE displays all PLMNs that it finds by scanning all frequency carriers. The UE

displays those PLMNs that are allowed as well as those that are not allowed. The usermakes a manual selection, according to the available access technology for the chosenPLMN, and the UE attempts registration on this PLMN, ignoring the contents of the

forbidden Location Area Identities (LAIs) and PLMN lists. If the user selects an availablePLMN in the forbidden PLMN list, the UE attempts to register and may receive a positiveacknowledgement from the CN. In this case, the PLMN is removed from the forbidden

list.

If the user does not select a PLMN, the selected PLMN is the one that was selectedbefore the PLMN selection procedure started. If this PLMN is no longer available, the UE

attempts to camp on an acceptable cell at any PLMN and enters the limited service state.The UE remains in that state until it is switched off or the user makes a manual PLMNreselection.

3.1.5 Roaming

Roaming is a service through which a UE is able to obtain services from another PLMN(Visited PLMN) than the HPLMN. The behavior that the UE must follow is specified by

agreements among the network operators. A UE in Automatic mode, having selectedand registered on a Visited PLMN (VPLMN), periodically attempts to return to its HPLMN.The time interval between consecutive attempts is stored in the USIM and is managed

by the network operator using a timer(The timer may have a value of between 6

minutes and 8 hours, with a step size of 6 minutes ). In the absence of a fixed

value, a default value of 30 minutes is used by the UE.

3.2 Strategy of Cell Selection and Reselection

Different types of measurements are used in different RATs and modes for the cell

selection and reselection.

The NAS can control the RAT(s) in which the cell selection should be performed, forinstance by indicating RAT(s) associated with the selected PLMN, and by maintaining a

list of forbidden registration area(s) and a list of NAS-specified service area in priorityorder. The UE will select a suitable cell and the radio access mode based onmeasurements and cell selection criteria.

In order to speed up the cell selection process, stored information for several RATs maybe available in the UE.

When camped on a cell, the UE will regularly search for a better cell according to the cell

reselection criteria. If a better cell is found, that cell is selected. The change of cell mayimply a change of RAT (that is, cell reselection between different systems).

For normal service, the UE has to camp on a suitable cell, tune to that cell's control

channel(s) so that the UE can:

Receive system information from the PLMN;


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Receive registration area information from the PLMN, e.g., location area and routing

area; and

Identify to which service area as specified by NAS that the serving cell belongs.

Receive other AS and NAS Information;

Receive paging and notification messages from the PLMN; and

Initiate call setup for outgoing calls or other actions from the UE.

3.2.1 States and State Transitions in Idle Mode

Figure 3 shows the states and procedures of cell selection and reselection in Idle Mode.

Figure 3 Idle Mode Cell Selection and Reselection


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InitialCell Selection

Any CellSelection

go herewhen noUSIM inthe UE

USIM inserted

Camped on

any cell

go here whenever anew PLMN is

selected

1

no cell information

stored for the PLMNcell information

stored for the PLMN

Storedinformation

Cell Selection

no suitable cell found

no suitablecell found

Cell Selectionwhen leaving

connectedmode

suitable cell found 2

suitablecell found

Campednormally

suitable cell found


leave

idle mode

return to

idle mode

Connectedmode

CellReselectionEvaluationProcess

suitablecell found

trigger


1

Cell Selectionwhen leaving

connectedmode

no acceptable cell found

acceptablecell found


suitablecell found 2

leaveidle mode

return toidle mode

Connectedmode

(Emergencycalls only)

CellReselectionEvaluationProcess


trigger

no acceptablecell found

NAS indicates thatregistration on selected

PLMN is rejected(except with cause #14

or #15 [5][16])

In any state, a new PLMN selection causes an exit to number 1

3.2.1.1 Cell selection process overview

Whenever a PLMN has been selected by NAS, the UE will attempt to find a suitable cell

to camp on. The NAS may control the cell selection by:

Providing information on RAT(s) associated with the selected PLMN;

Maintaining lists of forbidden registration areas;


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Providing a list of equivalent PLMNs.

One or several RATs may be associated with the selected PLMN. It depends on the UEcapability and PLMN plan.

The AS will attempt to find a suitable cell to camp on as specified in Section3.2.2.

If a suitable cell is found, the UE will select this cell to camp on, and report this event toNAS so that the necessary NAS registration procedures can be performed. When the

registration is successful, the UE enters in state Camped normally in order to obtainnormal service.

If the UE is unable to find any suitable cell of selected PLMN the UE will enter the Any

cell selectionstate and perform action of3.2.6 Any Cell Selection State.

3.2.1.2 Camped normally state overviewIn this state, the UE obtains normal service and performs the tasks specified in 3.2.3.

If after a Cell reselection evaluation process a better cell is found, the Cell reselectionprocedure is performed. If no suitable cell is found, the UE will enter the state Any cell

selection.

When UE leaves idle mode in order to enter the state Connected mode, the UE shallattempt to access the current serving cell. If the access attempt to the serving cell fails,

the UE will use the Cell reselectionevaluationprocedure.

3.2.1.3 Connected mode state overview

When returning to idle mode, the UE shall use the procedure Cell selection when leavingconnected mode in order to find a suitable cell to camp on and enter state Camped

normally. If a suitable cell is found, then the UE reports this event to NAS to be capableto perform necessary NAS registration procedures. If no suitable cell is found, the Storedinformation cell selectionprocedure will be used by the UE.

If no suitable cell is found in cell reselectionevaluation process, the UE enters the stateAny cell selection.

3.2.1.4 Any cell selection state overview

The state Any cell selection is also entered if the NAS indicates that a location

registration is rejected or there is no SIM/USIM in the UE. In this state the UE willbehave as specified in Section3.2.6 Any Cell Selection StateFF

If an acceptable cell is found, the UE will inform the NAS and camp on this cell and

obtain limited service, state Camped on any cell.

3.2.1.5 Camped on any cell state overview

In this state the UE obtains limited service. The UE will regularly attempt to find a

suitable cell, trying all RATs that are supported by the UE. If a suitable cell is found, this


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causes an exit to number 2 in Figure 3, to perform the procedure as specified in Section3.2.1.2 Camped normally state overview.

NOTE: The 'PLMN selection and reselection' process may select a new PLMN at any

time in idle mode, which in Figure 3 causes an exit to number 1, perform initial cellselection procedure (refer to Section3.2.1.1 Cell selection process overview).

3.2.2 Cell Selection Process

The UE will use one of the following two search procedures:

3.2.2.1 Initial cell selection

This procedure requires no prior knowledge of which RF channels are UTRA carriers.The UE will scan all RF channels in the UTRA/GSM bands to find a suitable cell in the

chosen PLMN. On each carrier, the UE need only search for the strongest cell. Once asuitable cell is found this cell shall be selected.

3.2.2.2 Stored Information cell selection

This procedure requires stored information of carrier frequencies and optionally alsoinformation on cell parameters, e.g. scrambling codes, from previously received

measurement control information elements. Once the UE has found a suitable cell theUE shall select it. If no suitable cell is found the Initial cell selection procedure will bestarted.

3.2.2.3 Cell selection criteria

The cell selection criterion S is fulfilled when:

for FDD cells: Srxlev > 0 AND Squal > 0

for TDD cells: Srxlev > 0

Where,

Squal = Qqualmeas(Qqualmin + QqualminOffset)

Srxlev = Qrxlevmeas(Qrxlevmin + QrxlevminOffset) Pcompensation

Qqualmeas: Measured cell quality value. Applicable only for FDD cells. The quality ofthe received signal expressed in CPICH Ec/N0(dB).


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Qrxlevmeas: Measured cell RX level value. This is received signal, CPICH RSCP forFDD cells (dBm), P-CCPCH RSCP for TDD cells (dBm) and RXLEV for GSM cells(dBm).

Qqualmin: Minimum required quality level in the cell (dB). Applicable only for FDD cells.QQualMin

Qrxlevmin: Minimum required RX level in the cell (dBm). (For serving cell: If

DltaQRxLevMin is broadcast, then Qrxlevmin =QrxLevMin+DltaQRxLevMin. IfDltaQRxLevMin is not broadcast, then Qrxlevmin +QRxLevMin. Whether to broadcastDltaQRxLevMinor not is controlled by DltaQRxLevMinPr. For neighbor cell: In Idle mode

or SIB12 is not broadcast, if DtQrxLvMnSib11 is not broadcast, then Qrxlevmin =QrxLevMin. In Idle mode or SIB12 is not broadcast, if DtQrxLvMnSib11 is broadcast,then Qrxlevmin =QrxLevMin+DtQrxLvMnSib11. In connected mode and SIB12 is

broadcast, if DtQrxLvMnSib12 is not broadcast, then Qrxlevmin =QRxLevMin. IfDtQrxLvMnSib12 is broadcast, then Qrxlevmin=QrxLevMin+DtQrxLvMnSib12. Whetherto broadcast DtQrxLvMnSib11 or not is controlled by DtQrxLvMnSib11Pr. Whether to

broadcast DtQrxLvMnSib12or not is controlled by DtQrxLvMnSib12Pr.

Notes: Whether to broadcast SIB12 is controlled by SIB12Ind

QqualminOffset(QqualminOffset): Offset to the signalled Qqualmin taken into account in

the Squal evaluation. The parameter is available only for FDD cells and SIB3. Whetherto broadcast QqualminOffset is controlled by parameter QqulmnOffstPre.

QrxlevminOffset(QrxlevminOffset): Offset to the signalled Qrxlevmin taken into account

in the Srxlev evaluation. The parameter is available only for SIB3. Whether to broadcastQrxlevminOffset is controlled by parameter QrxlvmnOffstPre.

Pcompensationmax(UE_TXPWR_MAX_RACH

P_MAX, 0)

UE_TXPWR_MAX_RACH: Maximum TX power level MaxRACHTxPwr on RACH (read

in system information) (dBm) (for cells under the RNC, it is the max value ofMaxRACHTxPw r (Prach); for cells under other RNC, it is the value of MaxRACHTxPwr(externalUtranCell)).

P_MAX: Maximum RF output power of the UE (dBm)

3.2.3 Camped Normally State

When camped normally, the UE will perform the following tasks:

Select and monitor the indicated PICH and PCH of the cell according to information

sent in system information;

Monitor relevant system information.

Perform necessary measurements for the cell reselection evaluation procedure.

Execute the cell reselection evaluation process.


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3.2.4 Rules of Cell Reselection Measurement

Different rules apply for cell reselection measurement when HCS is used and when HCSis not used.

3.2.4.1 Measurement rules for cell re-selection when HCS is not used

When the serving cell does not use HCS (UseOfHCS(utranCell) ), the measurementrules for cell reselection are:

In the following rules, the UE uses Squal for FDD cells and Srxlev for TDD cells for Sx:

1 If Sx > SIntraSearch, UE may choose to not perform intra-frequency measurements.

If Sx Sintersearch

If SsearchHCSis broadcast and Srxlev > SsearchHCS

The UE needs to perform inter-frequency measurements at least for the MBMSpreferred frequency layer when the following conditions are satisfied:

MBMS preferred frequency layer is configured and the current serving cell

does not belong to the MBMS preferred frequency layer.

Sx > Sintersearch

If SsearchHCSis broadcast and Srxlev > SsearchHCS.

The UE needs to perform inter-frequency measurements when any one of thefollowing conditions is satisfied:

Sx


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If Sx


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the value of HcsPrio (externalUtranCell).The HcsPrio of the GSM cell takes the value of(externalGsmCell).

In the following rules, the UE uses Squal for FDD cells and Srxlev for TDD cells for Sx:

1 For intra-frequency and inter-frequency measurement rules for UEs not in high-mobility

IF (Srxlev

ELSE

ENDIF

IF Sintrasearch is not sent for the serving cell, THEN

ENDIF

ENDIF

Whetherto broadcast Sintrasearchor not is controlled by SintraSearchPre.

If HCS(UseOfHCS(utranCell)) is used and if SsearchHCSor Sintersearch(FDD) isnot sent for the serving cell, UE will measure on all intra-frequency and inter-

frequency cells. Whether to broadcast SsearchHCS or not is controlled bySSearchHCSPre. Whether to broadcast SinterSearch or not is controlled by

SInterSearchPre.

2 For intra-frequency and inter-frequency measurement rules for fast-moving UEs:

This measurement rule applies when the HCS is used and the UE is in fast-movingstate and also the UE receives the broadcast message of NoHcsTCrMax,

NoHcsNCrand NoHcsTCrMaxHyst.

If the number of cell reselections during time period TCrMax exceeds NCr, or if thenetwork (via signaling of RRC release, RB re-configuration) has ordered the UE to

consider itself in high mobility state, the UE is triggered to enter fast-moving state.

In this high-mobility state, UE will


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IF(Srxlevs


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If the number of cell reselections during time period TCrMax exceeds NCr, or if thenetwork (via signaling of RRC release, RB re-configuration) has ordered the UE toconsider itself in high mobility state, the UE is triggered to enter fast-moving state.

In this high-mobility state, UE will

IF (Srxlev

ENDIF

Remarks: Whether to broadcast SHCSRat or not is controlled by SHCSRatPre.

Whether to broadcast SsearchRator not is controlled by OtherRATInfoPre.

When the number of cell reselections during time period TCRmax no longer exceedsNCr, the UE will

Continues in high-mobility state.

If the number of cell reselections during time period TCrmaxHyst does not exceed

NCr and also the network does not order the UE to stay in high-mobility state, then

the UE exits high-mobility state.

3.2.4.4 Measurement rules for inter-frequency and inter-RAT cell reselection whenabsolute priorities are used

If the UE has received absolute priority information for inter-frequency layers(AbsPriReselSwch (utranCell)), the UE shall follow these rules:

- The UE shall perform measurements of inter-frequency layers with a priority higher

than the priority of the current serving layer.

- For inter-frequency layers with a priority equal or lower than the priority of the current

serving layer:

- If SrxlevServ ingCell>Sprioritysearch1 and SqualServ ingCell > Sprioritysearch2 the UE may choosenot to perform measurements of inter-frequency layers of equal or lower priority.

- If SrxlevServ ingCell


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- The UE shall perform measurements of inter-RAT layers with a priority higher than thepriority of the current serving cell.

- For inter-RAT layers with a priority lower than the priority of the current serving cell:

- If SrxlevServ ingCell>Sprioritysearch1and SqualServingCell>Sprioritysearch2the UE may choose notto perform measurements of inter-RAT layers of lower priority.

- If SrxlevServ ingCell


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If parameter UE Inter-RAT Measurement Indicator(InterRatMIndPre)is set toFalse, UE shall not perform Inter-RAT Measurement. Else, UE shall performInter-RAT measurement according to the rules in3.2.4.1,3.2.4.2,3.2.4.3.

If parameter UE Inter-frequency FDD Measurement Indicator (FDDInterFMeasInd) orUE Inter-RAT Measurement Indicator(InterRatMIndPre) is set to True, UE shallperform Inter-frequency or Inter-RAT Measurement only in FACH measurement

occasion, other occasion shall be used to transmit user data. The FACH measurementoccasion is decided by parameter FACH Measurement Occasion Cycle LengthCoefficient(FachMeasK ) which is described in 3gpp 25.331 FACH measurementoccasion info.

3.2.4.7 Cell reselection criteria

The following cell re-selection criteria are used for intra-frequency cells, inter-frequencycells if no absolute priority information for any inter-frequency layer is available to the UE,

and inter-RAT cellsif no absolute priority information for any inter-RAT layer is availableto the UE for that RAT. For inter-frequency and inter-RAT layers in a RAT for whichabsolute priorities are defined, then the cell reselection criteria in subclause 3.2.4.8 shallapply.

If the serving cell uses the HCS (UseOfHCS (utranCell)) structure, the following cellreselection rule H is used for quality ranking in cell reselection.

Hs= Qmeas,s- Qhcss

Hn= Q

meas

,n- Qhcs

n

TO

n* L

n

If the cell does not use the HCS structure, the following cell reselection rule R is used for

quality ranking in cell reselection.

Rs = Qmeas,s + Qhysts+ Qoffmbms

Rn = Qmeas,n- Qoffsets,n+ Qoffmbms - TOn* (1Ln)

Where,

TOn= TEMP_OFFSETn* W(PENALTY_TIMEn Tn)

Ln= 0 if HCS_PRIOn= HCS_PRIOsLn= 1 if HCS_PRIOn HCS_PRIOs

W(x) = 0 for x < 0

W(x) = 1 for x >= 0


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Qmeas,s: Quality measurement result of serving cell.

Connected mode: When SIB4 is not broadcast, the parameter values are taken as in thecase of Idle mode; when SIB4 is broadcast, the value of QHcsEcNo (SIB4) is taken if

Ec/No is used as the quality measure, and the value of QHcsRSCP (SIB4) is taken ifRSCP is used as the quality measure.} Whether to broadcast SIB4 is controlled bySIB4Ind. Whether Ec/No or RSCP is used as the quality measure is controlled by

QualMeas.

Qmeas,n: Quality measurement result of neighbor cell.

Qhcs,n: This specifies the quality threshold levels of neighbor cells for applying

prioritised hierarchical HCS cell re-selection (Idle mode: If Ec/No is used as the qualitymeasure, the value of QhcsEcN0Sib11is taken; if RSCP is used as the quality measure,the value of QhcsRscpSib11 is taken. Connected mode: When SIB12 is not broadcast,

the parameter values are taken as in the case of Idle mode; when SIB12 is broadcast,the value of QhcsEcN0Sib12 is taken if Ec/No is used as the quality measure, and the

value of QhcsRscpSib12 is taken if RSCP is used as the quality measure.Whether tobroadcast SIB12 is controlled by SIB12Ind

Connected mode: When SIB4 is not broadcast, the parameter values are taken as in thecase of Idle mode; when SIB4 is broadcast, the value of QHyst1SPch is taken if RSCP

is used as the URA_PCH state reselection quality measure, and the value ofQHyst2SFach is taken if Ec/No is used as the CELL_FACH state reselection qualitymeasure. Whether to broadcast SIB4 is controlled by SIB4Ind.

Qoffmbms: This specifies the offset added to cells belonging to the MBMS PL when adecision of HCS cell R reselection rule is being made.

Connected mode: When SIB12 is not broadcast, the parameter values are taken as in

the case of Idle mode; when SIB12 is broadcast, the value of Qoffset1SNSib12 is takenif RSCP is used as the reselection quality measure, and the value of Qoffset2SNSib12istaken if Ec/No is used as the reselection quality measure. Whether to broadcast SIB12

is controlled by SIB12Ind

Tn: The timer used after cell reselection. The rules to start Tnare as follows:

Tn is implemented for each neighbouring cell. Tn will be started from zero when one

of the following conditions becomes true:

If HCS_PRIOn HCS_PRIOsand Qmeas,n > Qhcsn

or

If HCS_PRIOn = HCS_PRIOs and

for serving FDD and neighbour FDD cells if the quality measure for cellselection and reselection is set to CPICH RSCP in the serving cell, and

Qmeas,n> Qmeas,s + Qoffset1s,n

or

for serving FDD and neighbour FDD cells if the quality measure for cellselection and reselection is set to CPICH Ec/No in the serving cell, and



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or

for all other serving and neighbour cells:


Tnfor the associated cell will be stopped as soon as any of the above conditions are

no longer fulfilled.. Any value calculated for TOn is valid only if the associated timer

Tnis still running otherwise TOnwill be set to zero.

At cell-reselection, a timer Tn is stopped only if the corresponding cell is not a

neighbour cell of the new serving cell, or i f the criteria given above for starting timer

Tn for the corresponding cell is no longer fulfilled with the parameters of the new

serving cell. On cell re-selection, timer Tn will be continued to be run for the

corresponding cells but the criteria given above will be evaluated with parameters

broadcast in the new serving cell if the corresponding cells are neighbours of the

new serving cell.

Connected mode: When SIB12 is not broadcast, the parameter values are taken as inthe case of Idle mode; when SIB12 is broadcast, the value of TempOffset1Sib12 istaken if RSCP is used as the reselection quality measure and the value of

TempOffset2Sib12is taken if Ec/No is used as the reselection quality measure. Whetherto broadcast S IB12 is controlled by SIB12Ind)}. If HCS (UseOfHCS (utranCell) ) is used,TEMP_OFFSETn is used to calculate TOn. If HCS (UseOfHCS (utranCell) ) is not used,

TEMP_OFFSETnis not applied when calculating Rn.

HCS_PRIOn: This specifies the HCS priority level for neighbouring cells (non-HCS cell:

The HcsPrio of the current RNC cell takes the value of HcsPrio(utranCell). The HcsPrioof the neighbor RNC cell takes the value ofHcsPrio (externalUtranCell). The HcsPrio ofthe GSM cell takes the value of HcsPrio (externalGsmCell). If not configured, it is 0default. For value of HCS cells, refer to Value of HCS Priority in Cell reselectionmeasurement rule when the hierarchical cell structure (HCS) is used.

HCS_PRIOs: This specifies the HCS priority level for serving cell. (non-HCS cell: TheHcsPrio of the current RNC cell takes the value of HcsPrio(utranCell). The HcsPrio of

the neighbor RNC cell takes the value ofHcsPrio(externalUtranCell). The HcsPrio of theGSM cell takes the value of HcsPrio (externalGsmCell). For value of HCS cells, refer toValue of HCS Priority in Cell reselection measurement rule when the hierarchical cellstructure (HCS) is used.

The cell are ranked by quality according to the above defined R or H criteria usingCPICH RSCP (for FDD), P-CCPCH RSCP (for TDD) and the measurement result of

averaged received signal level (for GSM) as the calculation quantity of Qmeasn,Qmeass, R or H. The best ranked cell is the cell with the highest R or H value.

For the cell selection and reselection parameters: Whether Qhcs, TCrmax, NCR and

TCrmaxHyst are configured is controlled by HcsSrvCelInfoPre. Whether the HCS-relatedparameters in neighbor cell such as HCS_PRIO, Qhcs, Penalty_time,Temporary_offset1 and Temporary_offset2 are configured is controlled by UseOfHCS

(utranRelation) and UseOfHCS(gsmRelation).

If a TDD or GSM cell is ranked as the best cell, then the UE will perform cell re-selectionto that TDD or GSM cell and camps on the chosen cell.


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If an FDD cell is ranked as the best cell and the quality measurement for cell selectionand re-selection is set to CPICH RSCP, the UE will perform cell re-selection to that FDDcell and and camps on the chosen cell (If this cell is found to be not suitable, the UE will

behave according to Highest ranked cells with cell reservations, access restrictions or

unsuitable for normal camping).

If an FDD cell is ranked as the best cell and the quality measure for cell selection and re-

selection is set to CPICH Ec/No, the UE shall perform a second ranking of the FDD cellsaccording to the R criteria specified above, but using the quality measure CPICH Ec/Nofor deriving the Qmeas,n and Qmeas,s and calculating the R values of the FDD cells (If this

cell is found to be not suitable, the UE will behave according to Highest ranked cellswith cell reservations, access restrictions or unsuitable for normal camping ).

In all cases, the UE will reselect the new cell, only if the following conditions are met: 0}

The new cell is better ranked than the serving cell during a time interval

Treselectionaccording to the R or H criteria. If Treselections,PCH

is provided in SIB4,

the URA_PCH state timer takes the value of TreselectionPch; if TReselectionFach

is provided in SIB4, the CELL_FCH state timer takes the value of TreselectionFach.

For hierarchical cell structures when high mobility state has not been detected, if

according to the HCS rules the serving cell is not ranked then all the ranked cells

are considered to be better ranked than the serving cell. In case the UE reselects a

cell on an MBMS preferred frequency to receive an MBMS service not available on

the current frequency, the UE may reduce interval TreselectionS, TreselectionS, PCH

and TreselectionS, FACH. (Whether to configure SIB4 is controlled by SIB4Ind).

More than 1 second has elapsed since the UE camped on the current serving cell.

The timers Treselection, TReselectionPch and TReselectionFachwill be multiplied

by scaling factor if the following conditions are satisfied:

The high mobility state of cell is detected and "Speed dependent ScalingFactor

for_Treselection" (SpSf) is broadcast on system information (whether broadcast is

controlled by SpSfPre), then TreselectionS, TReselectionPch and

TReselectionFach will be multiplied by the scaling factor SpSf in intra-frequency

measurement and the result is the actually used TreselectionS , TReselectionPch

and TReselectionFach.

The high mobility state of cell is not detected and " Inter-Frequency ScalingFactorfor Treselection" (InterFreqSf) is broadcast on system information (whether

broadcast is controlled by InterFreqSfPre), then Treselection, TReselectionPch and

TReselectionFach will be multiplied by the scaling factor InterFreqSf in inter-

frequency measurement and the result is the actually used TreselectionS,

TReselectionPch and TReselectionFach.


for_Treselection" (SpSf) and "Inter-Frequency ScalingFactor for Treselection "

(InterFreqSf) are broadcast on system information, then Treselection,

TReselectionPch and TReselectionFach will be multiplied by the scaling factors


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SpSfand InterFreqSf in inter-frequency measurement and the result is the actually

used TreselectionS, TReselectionPch and TReselectionFach.

The high mobility state of cell is not detected and "Inter -RAT ScalingFactor for

Treselection" (InterRatSf) is broadcast on system information (whether broadcast is

controlled by InterRatSfPre), then Treselection, TReselectionPch and

TReselectionFach will be multiplied by the scaling factor InterRatSf in inter-RAT

measurement and the result is the actually used Treselection, TreselectionPch and

TReselectionFach.


for_Treselection" (SpSf) and "Inter-RAT ScalingFactor for Treselection "

(InterRatSf) are broadcast on system information, then TreselectionS,

TReselectionPch and TReselectionFach will be multiplied by the scaling factors

SpSfand InterRatSf in inter-RAT measurement and the result is the actually used

Treselection, TReselectionPch and TReselectionFach.

In case scaling is applied to Treselection or TReselectionPch, the UE will round up

the Treselection or TReselectionPch after all scalings to the nearest second. In

case scaling is applied to TReselectionFach, the UE will round up the result after all

scalings to the nearest 0.2 seconds.

3.2.4.8 Absolute priority based criteria for inter-frequency and inter-RAT cell reselection

Absolute priorities of different absolute priority layers may be provided to the UE. The

following cell reselection criteria are used for inter-frequency cells if absolute priority

information for inter-frequency is available to the UE, and inter-RAT cells if absolute

priority information for inter-RAT is available to the UE.

If System Information Block 18 with UTRAN information is provided then the UE shall

apply inter-frequency priority rules below only to UTRAN cells of the selected PLMN or

equivalent PLMNs. If System Information Block 18 is not provided, or is provided but

contains no information for UTRAN, then the rules below apply for the entire UTRAN

RAT.

If System Information Block 18 with GERAN information is provided then the UE shall

apply the GERAn RAT priority rules below only to GERAN cells of the selected PLMN or

equivalent PLMNs. If System Information Block 18 is not provided, or is provided but

contians no information for GERAN, then the rules below apply for the entire GERAN

RAT.

If priority information is provided for any inter-frequency layers, cells belonging to inter-

frequency layers for which no priority or no threshold is assigned shall not be considered

for reselection.


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If priority information is provided for any inter-RAT layers in a RAT, cells belonging to

layers in that RAT for which no priority or no threshold is assigned shall not be

considered for reselection.

If none of the inter-frequency layers in UTRAN are provided with both priority and

threshold parameters, the cell reselection criteria in subclause 3.2.4.7 shall apply for

inter-frequency layers in UTRAN.

If none of the inter-RAT layers in a RAT are provided with both priority and threhsold

parameters, the cell reselection criteria in subclause 3.2.4.7 shall apply for that RAT.

For all inter-frequency layers or all inter-RAT layers belonging to one RAT, either the

criteria below or the criteria in subclause 3.2.4.7 shall apply.

The following definitions apply:

- Criterion 1: the SrxlevnonServingCell,xof a cell on an evaluated higher absolute priority is

greater than Threshx,highduring a time interval Treselect ion;

- Criterion 2: SrxlevServ ingCell < Threshserving,low or SqualServ ingCell


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Cell reselection to a cell on a lower absolute priority layer than the camped frequency

shall be performed if criterion 3 is fulfilled.

If more than one cell meets the above criteria, the UE shall reselect the cell with the

highest SrxlevnonServingCell,x among the cells meeting the criteria on the highest absolute

priority layer.

The UE shall not perform cell reselection to cells for which the cell selection criterion S is

not fulfilled.

The UE shall not perform cell reselection until more than 1 second has elapsed since the

UE camped on the current serving cell.

In all the above criteria the values of Treselections, Treselections,PCHor Treselections,FACH

apply for Treselection and are scaled according to the UE mobility state and target RAT,

as specified in 3.2.4.7.

3.2.5 Cell Selection When Leaving Connected Mode

When returning to idle mode from connected mode, the UE will select a suitable cell tocamp on. Candidate cells for this selection are the cell(s) used immediately before

leaving connected mode. If no suitable cell is found, the UE will use the Storedinformation cell selection procedure in order to find a suitable cell to camp on.

When returning to idle mode after an emergency call on any PLMN, the UE will select an

acceptable cell to camp on. Candidate cells for this selection are the cell(s) used

immediately before leaving connected mode. If no acceptable cell is found, the UE willcontinue to search for an acceptable cell of any PLMN in state Any cell selection.

3.2.6 Any Cell Selection State

In this state, the UE will attempt to find an acceptable cell to camp on, trying all RATsthat are supported by the UE and searching first for a high quality cell, till an acceptable

cell is found.

3.2.7 Camped on Any Cell State

In this state, the UE will perform the following tasks:

Select and monitor the indicated PICH and PCH of the cell

Monitor relevant System Information

Perform necessary measurements for the cell reselection evaluation procedure

Execute the cell reselection evaluation process on the following occasions/triggers:

UE internal triggers


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When information on the BCCH used for the cell reselect ion evaluation procedure

has been modified

Regularly attempt to find a suitable cell trying all RATs that are supported by the UE.

If a suitable cell is found, this causes an exit to number 2 in Figure 3.

In this state the UE is not permitted to receive any MBMS services.

3.2.8 Cell Reservations and Access Restrictions

There are two mechanisms, which allow an operator to impose cell reservations oraccess restrictions.

The first mechanism uses indication of cell status and special reservations for control of

cell selection and re-selection procedures.

The second mechanism will allow preventing selected classes of users from sendinginitial access messages for load control reasons. At subscription, one or more Access

Classes are allocated to the subscriber and stored in the USIM, which are employed forthis purpose.

3.2.8.1 Cell status and cell reservations

Cell status and cell reservations are indicated with the Cell Access Restriction

Information Element in the System Information Message by means of three InformationElements:

Cell barred CellBarredInd

Cell Reserved for operator use OperatorUseInd

Cell reserved for future extension CellRsvExt

In state CellBarredInd, its necessary to configure InFreqReselInd and TBarred for theUE. If InFreqReselInd is Not Allowed, the processing strategy of the intra-frequencyneighbor cell in state CellBarred is the same as the current cell in state CellBarred. TheUE will not attempt to reselect the cell in state CellBarred within the Tbarred time period.

After Tbarred expires, the UE will attempt again to reselect the cell.

When cell status is indicated as "not barred", "not reserved" for operator use and "notreserved" for future extension

All UEs will treat this cell as candidate during the cell selection, cell evaluation and

cell re-selection procedures in Idle mode and in Connected mode.

When cell status is indicated as "not barred", "not reserved" for operator use and

"reserved" for future extension


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UEs will behave as if cell status "barred" is indicated using the value "not allowed"

in the information element (IE) "Intra-frequency cell re-selection indicator" and the

maximum value for Tbarred

When cell status is indicated as "not barred" and "reserved" for operator use,

UEs assigned to Access Class 11 or 15 will treat this cell as candidate during the

cell selection and cell re-selection procedures i f the cell belongs to the home PLMN.

UEs assigned to an Access Class in the range 0 to 9 and 12 to 14 shall behave as if

cell status "barred" is indicated using the value "not allowed" in the IE "Intra-

frequency cell re-selection indicator" and the maximum value for Tbarred

When cell status "barred" is indicated,

The UE is not permitted to select/re-select this cell, not even for emergency calls.

The UE will ignore the "Cell Reserved for future extension (Cell Reservation

Extension) use" IE.

The UE is not permitted to receive any MBMS services.

The UE will select another cell according to the following rule:

If the "Intra-frequency cell re-selection indicator (InFreqReselInd)" IE in Cell AccessRestriction IE is set to value "allowed", the UE may select another cell on the samefrequency if selection/re-selection criteria are fulfilled.

If the UE is camping on another cell, the UE will exclude the barred cell from the

neighbour cell list until the expiry of a time interval Tbarred. If the UE does not select

another cell, and the barred cell remains to be the "best" one, the UE will after

expiry of the time interval Tbarredagain check whether the status of the barred cell

has changed.

If the "Intra-frequency cell re-selection indicator" IE is set to "not allowed" the UE

will not re-select a cell on the same frequency as the barred cell. During an ongoing

emergency call, the Intra-frequency cell re-selection indicator IE" will be ignored, i.e.

even if it is set to "not allowed" the UE may select another intra-frequency cell.

If the barred cell remains to be the "best" one, the UE will after expiry of the time

interval Tbarredagain check whether the status of the barred cell has changed.

The reselection to another cell may also include a change of RAT.

For the cell access restriction, the barred access indication of different access classes

(AC) can also be configured through the parameter ACBarredOmcr.The behavior of theUE corresponding to the AC with barred access is the same as the cell withCellBarredInd.


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3.2.8.2 Access control

Information on cell access restrictions associated with the Access Classes is broadcastas system information,

The UE will ignore Access Class related cell access restrictions when selecting a cell to

camp on. That is, it will not reject a cell for camping on because access on that cell isnot allowed for any of the Access Classes of the UE. A change of the indicated accessrestriction will not trigger cell re-selection by the UE.

Access Class related cell access restrictions will be checked by the UE before sendingan RRC CONNECTION REQUEST message when entering Connected Mode fromUTRAN Idle mode. When the initial access that entered connected mode is triggered by

inter-RAT cell reselection or a UE already is in Connected Mode, cell access restrictionsassociated with the Access Classes will not apply for the UTRAN.

3.2.8.3 Emergency call

Usually all cells allow emergency call, regardless of the state indication and cellreservation.

A restrict ion on emergency calls, if needed, will be indicated in the "Access class barredlist" IE. If access class 10 is indicated as barred in a cell, UEs with access class 0 to 9 orwithout an IMSI are not allowed to initiate emergency calls in this cell. For UEs with

access classes 11 to 15, emergency calls are not allowed if both access class 10 andthe relevant access class (11 to 15) are barred. Otherwise, emergency calls are allowedfor those UEs.

3.2.9 Cell Reselection Process in RRC Connected Mode

In RRC connected mode, the cell reselection process with the UTRA access technologyis the same as that in Idle mode.

3.2.10 Parameters and Configuration for Cell Selection and Reselection

The system information SIB3 related with cell selection and reselection must beconfigured. SIB4 is optional. Whether to configure SIB4 is controlled by SIB4Ind. The IE

of SIB3 is totally the same as that of SIB4. The system uses different records in thesame datasheet to configure the SIB or SIB4 message and the purpose of the record is

identified through Sib3orSib4. The cell selection and reselection in IDLE mode employsparameters in SIB3. The cell selection and reselection in connected mode and IDLEmode employs parameters in SIB4 if SIB4 is configure, or parameters in SIB3 if SIB4 isnot configured.

3.2.11 SIB11bis usage

For current 3GPP specification, one System Information Block can be divided into 16

segmentations, each of which can include at most 222 bits. That means one SystemInformation Block can include at most 3552 bits. But for current specification, up to 96neighbor cells are supported at the same time which needs more bits than 3552 to carry.

To support up to 96 neighbor cells are supported at the same time, SIB11bis will be


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used. Neighbor cell to be carried by SIB11 or SIB11bis is decided bySib11orSib11bis(utranRelation /gsmRelation).

3.3 Strategy of LA and RA Update

In the UE, the AC should report registration area information to NAC.

Once the UE finds the cell to register, it will register on the corresponding PLMN. If the

LAI or RAI read from system information are different from those stored in USIM beforethe UE switches off, the UE will perform LA or RA registration update. When the UE inIDLE mode moves to a new LA or RA or PLMN, it will perform registration area update.

The process of LA or RA update is controlled by CN and is transparently transmitted asthe RAN is concerned.

There are three types of registration area update: normal update, periodic update and

IMSI attach and detach.

3.3.1 LA and RA Structure

The LA is an area to which the CN sends a paging message for circuit switched service

and the RA is an area to which the CN sends a paging message for packet switchedservices. Each area, LA or RA, may consist of several cells of one or more RNC, whichare connected to the same core network. The RA is required if the RNC is connected to

a packet switched CN. Note that each cell could belong to only one LA and one RA.

The LA is identified by a combination of PLMN Identity and Location Area Code (LAC).

The RA is identified by a combination of PLMN and Routing Area Code (RAC).

3.3.2 Normal LA and RA Updating

A UE executes a normal registration update when, in a cell belonging to a new LA or RA,it is switched on or leaves the Connected mode. Normal registration update is also

performed when the UE, in Idle mode, moves in a cell belonging to a new LA or RA orPLMN. The UE reads the LAI and the RAI in the system information and detects thatone or both of the received area identities differ from the ones stored on the USIM. If the

LAI received from the system information is not in the forbidden LAIs list, an LA and/orRA update request is sent by the UE. If the LAI is forbidden, the UE tries to select

another cell belonging to a permitted LAI or another PLMN.

3.3.3 Periodic LA and RA Updating

Periodic LA and RA updating is used to notify the network of the UEs availability, and toavoid unnecessary paging attempts for a UE that has lost coverage and is not able to

inform the CN that it is inactive. The periodic LA update procedure is controlled by atimer, called t3212, whose value is sent to UEs with broadcast message. The periodicRA update is controlled by a timer, called t3312 (not a radio parameter), whose value is

sent by the CN to the UE in the IMSI attach or in the routing area update messageaccept.


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3.3.4 IMSI Attach/Detach

A location registration request indicating IMSI attach is made when the UE is activated inthe same LA in which it was deactivated, and the system information (att) indicates that

IMSI attach/detach is used. If the parameter att is set to 1, the UE sends an attachordetach message when it is powered on or off indicating whether the UE is active orinactive. The IMSI attach/detach procedure allows the UE to avoid unnecessary paging

attempts from the CN.

The CN avoids performing paging attempts when IMSI detach is applied and the UE isswitched off. When the UE is switched on and the IMSI attach/detach procedure is

applied, the UE performs a location registration request, indicating IMSI attach, if it is inthe same LA or RA in which it was switched off. If the registration area is changed, anormal LA update is performed by the UE.

3.4 Strategy of URA UpdateIn state URA_PCH, the procedure URA Update is initiated in the following cases with the

trigger reason of change of URA:

If the new cell that the UE camps on is not in the same URA area as the former cell

that the UE camps on, the URA Update is triggered (to perform the Figure 4 URA

update procedure, basic flow).

The UE enters a cell that has no URAs defined. This will trigger a release of the

RRC Connection and the UE enters Idle mode (The URA ID list in SIB2 is empty or

the SIB2 information is not received) (to perform Figure 5 URA update procedure,failure case

-The T305 in the IE UE Timers and constants in connected mode" set to non-

infinity and T305 expires (to perform Figure 4 URA update procedure, basic flow).

If the UE doesnt support HS -DSCH reception but receives the IE "HS-DSCHpaging system information", and the IE is not save for the moment, and the 12

MSBs (high 12 bits) of "SRNC identity" in U_RNTI does not equal to the 12 MSBs of

"Cell identity" in SIB3 (to perform Figure 4 URA update procedure, basic flow ).

3.4.1 Process of URA Update

Figure 4 URA update procedure, basic flow


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UE UTRAN

URA UPDATE

URA UPDATE CONFIRM

Figure 5 URA update procedure, failure case

UE UTRAN

URA UPDATE

RRC CONNECTION RELEASE

3.5 Strategy of CELL Update

A UE triggers cell update in the following cases:

Cell reselection in state CELL_FACH (to perform Figure 6 Cell update procedure,

basic flow)

Radio link failure in state CELL_DCH (to perform Figure 7 Cell update procedurewith physical channel reconfiguration flow for call re-establishment)

T305 periodic cell update (to perform Figure 6 Cell update procedure, basic flow).

In state CELL_FACH, when the UE enters an area with acceptable coverage after

coverage loss, periodic cell update is performed (to perform Figure 6 Cell updateprocedure, basic flow)

The UE in state URA_PCH sends data in uplink (to perform Figure 6 Cell updateprocedure with radio bearer reconfiguration )

The UE in state URA_PCH (can be originated by UTRAN or CN) (to perform Figure

8 Cell update procedure with radio bearer reconfiguration )

The UE in state CELL_FACH/CELL_DCH detects that an RLC unrecoverable error

of AM RLC entity (to perform Figure 7 Cell update procedure with physical channel

reconfiguration )

MBMS p-t-p RB request in state URA_PCH/CELL_FACH (to perform Figure 6 Cell

update procedure, basic flow)


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MBMS Counting in state URA_PCH/CELL_FACH (to perform Figure 6 Cell updateprocedure, basic flow)

3.5.1 Process of CELL Update

Figure 6 Cell update procedure, basic flow

UE UTRAN

CELL UPDATE

CELL UPDATE CONFIRM

Figure 7 Cell update procedure with physical channel reconfiguration

UE UTRAN

CELL UPDATE

CELL UPDATE CONFIRM

PHYSICAL CHANNEL RECONFIGURATION COMPLETE

Figure 8 Cell update procedure with radio bearer reconfiguration

UE UTRAN

CELL UPDATE

CELL UPDATE CONFIRM

RADIO BEARER

RECONFIGURATION COMPLETE


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3.6 Random Access Process of PRACH

3.6.1 PRACH Structure

The Physical Random Access Channel (PRACH) carries the RACH transport channel.As shown in Figure 9 the PRACH comprises one or more random access preambles of4096 chips long and the random access message of 10ms or 20ms.

Figure 9 PRACH Structure

Message partPreamble

4096 chips10 ms (one radio frame)

Preamble Preamble

Message partPreamble

4096 chips 20 ms (two radio frames)

Preamble Preamble

3.6.2 Preamble Part

The preamble part of PRACH is 4096 chips long. It is obtained by repeating the 16-chipsignature (configured through Signatureunder Prach) for 256 times and then processed

with RPACH preamble scrambling (PreamScraCode).

3.6.3 Message Part

The message part of PRACH is made up of frames that are 10ms and 20ms long, the

same as TTI (Transmission Time Interval) of RACH. Figure 10 shows the 10ms longmessage part of PRACH. A 10ms-long radio frame is made up of 15 slots and each slotcomprises the parallel data part and control part. The 20ms-long PRACH message is

made up of two 10ms-long PRACH message.

Figure 10 Structure of PRACH Message


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Pilot

Npilotbits

Data

Ndatabits

Slot #0 Slot #1 Slot #i Slot #14

Tslot= 2560 chips, 10*2kbits (k=0..3)

Message part radio frame TRACH= 10 ms

Data

Control

TFCI

NTFCIbits

One slot of the PRACH message can carry 10*2k bits. k=0, 1, 2 and 3 corresponds

respectively to the spectrum spreading factors adopted by the message part: SF=256,128, 64 and 32. The minimum spectrum spreading factor available for the PRACH

message part is configured with the parameter AvailableSF.

The PRACH message control part also comprises 2560 chips, including 8 known pilotbits and 2 transport format combination indicator (TFCI) bits indicating the transport

format of transmitted data, which is equivalent to the spectrum spreading with SF=256code words.

The transport format adopted for the data part is sent in SIB 5. ZTE RNC uses the

following parameters to configure the transport format of PRACH:

CPCIdof PRACH indicates the common physical channel identity of PRACH.

Sib5OrSib6 of PRACH determines that the related configuration information of

PRACH corresponding to CPCIdis to be broadcast in SIB5 or SIB6.

TfcsIndexof PRACH indicates the index of TFCS used by PRACH corresponding to

CPCId.

CtfcNumand Ctfc of PRACH indicates the number of CTFCs and label of TFC of

PRACH of TfcsIndex, that is, Ctfc is the array parameter and the dimension of the

array takes the value of CtfcNum.

PrachCPCId of RACH indicates the common physical channel identity of PRACH

that takes the same value of CPCId of PRACH.

CTCIdof RACH indicates the common transport channel identity of RACH mapped

on the PRACH with the common physical channel identity of PrachCPCId.

TfsIndex of RACH indicates the TFS index of RACH corresponding to CTCId.

TrBlkNum of Tfs indicates the number of transport blocks in the transport format

corresponding to RACH of TfsIndex.


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RlcSize of Tfs indicates the size of transport block corresponding to RACH of

TfsIndex.

TTI of Tfs indicates the transmission time interval corresponding to RACH of

TfsIndex.

RlcSize and TTI of Tfs are array parameters. Dimension of the array equals the

value of TrBlkNum, the label of the element in the array equals the value of Ctfc of

PRACH.

Figure 11 shows the mapping relation among the above described parameters:

Figure 11 Mapping Relation of PRACH-related Parameters

Sib5OrSib6

TfcsIndex CtfcNum + Ctfc

CPCId

/PrachCPCId

CTCId

TfsIndex RlcSize + TrBlkNum + TTI

3.6.3.1 Selection of channelized code of PRACH message part

The spectrum spreading code used by the control part of PRACH is cc= Cch,256,m, where

m = 16s + 15. The spectrum spreading code used by the data part of PRACH is c d=Cch,SF,m, where SF=256, 128, 64 and 32 are the spectrum spreading factor of the data

part, m = SFs/16, s(0 s 15) is the serial number of the signature used by the

PRACH preamble part among all 16 PRACH preamble signatures. The minimumspectrum spreading factor available for the PRACH message is controlled by

AvailableSF. The UE selects the size of the spectrum spreading factor adaptively

according to the size of the PRACH message part, the AvailableSF configured in thenetwork side and also the PunctLimit. The selection method is described in the following:

A PRACH message with the 10ms-long radio frame can carry the number of data bits as

determined by the spectrum spreading factor, relation of the two is listed in the followingtable:

Table 1 Number of Bits Carried in PRACH Message vs. Spectrum Spreading Factor

Slot Format#i

Channel BitRate (kbps)

Channel SymbolRate (ksps)

SF Bits/Frame

Bits/Slot

Ndata

0 15 15 256 150 10 10

1 30 30 128 300 20 20

2 60 60 64 600 40 40

3 120 120 32 1200 80 80


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The number of bits that can be carried by a 10ms-long radio frame of PRACH messageis indicated respectively as N256, N128, N64, N32, corresponding to the cases whenSF=256, 128, 64 and 32. Niindicates the number of bits to be sent by the UE in a 10ms-

long PRACH radio frame. According toAvailableSF, SET0={N256,, NAvailableSF} is set up.

SET1 = {Ndata in SET0 such that (Ndata - Ni)0}, that is, SET1 is the set of elementsgreater than Niin SET0.

If SET1 is not empty, then the spectrum spreading factor corresponding to Ndatawith thesmallest value in SET1 is selected as the spectrum spreading factor for the PRACHmessage part.

If SET1 is empty, then set up SET2:

SET2 = {Ndata in SET0 such that (Ndata PunctLimitNi)0}, that is, SET2 is the set ofelements greater than PunctLimitNi in SET0, PunctLimitNi is the remaining number of

bits of the PRACH message part after the operation of configured PunctLimit subtracted

by (1-PunctLimit)Ni.

The spectrum spreading factor corresponding to Ndatawith the smallest value in SET2 is

selected as the spectrum spreading factor for the PRACH message part.

3.6.4 Random Access Process of Physical Layer

Before the random access process of the physical layer is initialized, the physical layer

will receive the following information from the RRC layer:

Preamble scrambling code: reamScraCode

Length of random access message (10ms or 20ms)

AICH transmit time (AichTranTime )

Available signature (AsigStIdx and AsigEndIdx indicate the start and end serial

numbers of the valid signature sequence) and valid RACH number (AsubChNum)

corresponding to every ASC.

Preamble power ramp step (PRStep) for random access

Maximum preamble retransmission times (MaxPreamRetrans)

Power offset of the last sent preamble and the random access message control part

(POPpm)

The transport format set of access message part (configured through TfcsIndex

indexing to actual TFCS) includes the data channel corresponding to TFC and the

power gain factor of control channel (configured separately through BetaD and

BetaC ofPRACH)

Before the random access process of the physical layer is initialized, the physical layerwill receive the following information from the MAC layer:


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Transport format of the PRACH message part.

ASC of PRACH transmission.

Data block that is sent.

The random access process of the physical layer is as follows:

1 Determine the available access slot set according to the RACH (AvailSubChanNum )corresponding to ASC and select an available access slot from the set. If t here is no

available access slot in the selected slot set, select ransomly an access slot fromthe next available access slot according to the RACH corresponding to ASC.

2 Select randomly a signature from the valid signature set corresponding to ASC.

3 Set the preamble retransmission counter to the maximum preamble retransmissions

(MaxPreamRetrans).

4 The UE calculates the initial transmit power of preamble (involved parameters

include BetaD, BetaC, POPpm and ConstValof PRACH, refer to ZTE UMTS PowerControl Feature Guide).

5 If the preamble transmit power worked out by the UE exceeds the allowed UL

maximum transmit power (MaxRACHTxPwr (Prach) ), then set the preambletransmit power to the same as the maximum transmit power. If the preambletransmit power worked out by the UE is below the allowed UL minimum transmit

power, then set the preamble transmit power to the same as the maximum transmitpower, then set the preamble transmit power to the same as the minimum transmitpower. Next, transmit the random access preamble according to the selected

signature, UL access slot and preamble transmit power. Only when the ratio of thepreamble power received by NodeB to the interference is greater than PreamThs,NodeB will send positive response on the AICH.

6 If the UE fails to receive, in the DL access slot corresponding to the slot that sendsthe UL access preamble, the positive or negative response (AI = +1 nor 1)corresponding to the selected signature on AICH, the UE will perform the following:

Select the next available access slot set from the valid RACH numbers corresponding toASC.

Randomly select a valid signature from the valid signature set corresponding to ASC.

Increase the transmit power of random access preamble by one PRStep. If the transmitpower of random access preamble exceeds the maximum allowed transmit power 6dB,the UEs physical layer reports "No ack on AICH" to the MAC layer and exit the physicalrandom access process.

Decrease the preamble retransmission counter by 1.

If the preamble retransmission counter is greater than 0, perform step 5 again.

Otherwise, the UE physical layer reports "No ack on AICH" to the MAC layer and exitsthe physical random access process.

1 If the UE receives, in the DL access slot corresponding to the slot that sends the UL

access preamble, the negative response corresponding to the selected signature on


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AICH, the UE physical layer reports "Nack on AICH received" to the MAC layer andexits the physical random access process.

2 If the UE receives, in the DL access slot corresponding to the slot that sends the UL

access preamble, the positive response corresponding to the selected signature onAICH, then the UE sends the message part of random access in the third ULaccess slot (AichTranTime=0) after the slot that sends the random access preamble

for the last time or in the fourth UL access slot (AichTranTime=1). The transmitpower offset between the control part of the random access message and the lastrandom access preamble is configured with the parameter POPpm.

3 The UE physical layer reports "RACH message transmitted" to the MAC layer andexits the physical random access process.

3.6.4.1 RACH access slot set

PRACH has totally 15 slots of 20ms and the slots belongs to two access slot sets.Access s lot set 1 includes these slots: slot 0~7 starting from p-a chips before the DL P-CCPCH frame of SFN mod 2=0. Access slot set 2 includes these slots: slot 8~14 startingfrom p-a2560chips before the DL P-CCPCH frame of SFN mod 2=0. Figure 12 showsthe diagram of the two access slot sets:

Figure 12 Relation between the PRACH Access Slot and DL AICH

AICH accessslots

10 ms

#0 #1 #2 #3 #14#13#12#11#10#9#8#7#6#5#4p-a

#0 #1 #2 #3 #14#13#12#11#10#9#8#7#6#5#4

PRACHaccess slots

SFN mod 2 = 0 SFN mod 2 = 1

10 ms

Access slot set 1 Access slot set 2

3.6.4.2 RACH

RACH defines a subset of all UL access slots.

Table 2 gives the access slot mapping of different RACHs corresponding to SFN:

Table 2 Mapping Relation Between Available UL Access Slot and RACH

SFN modulo 8 of

corresponding P-CCPCH frame

Sub-channel number

0 1 2 3 4 5 6 7 8 9 10 11

0 0 1 2 3 4 5 6 7

1 12 13 14 8 9 10 11

2 0 1 2 3 4 5 6 7


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3 9 10 11 12 13 14 8

4 6 7 0 1 2 3 4 5

5 8 9 10 11 12 13 14

6 3 4 5 6 7 0 1 2

7 8 9 10 11 12 13 14

3.6.4.3 PRACH/AICH timing relation

The AICH frame is 20ms long and divided into 15 slots, each slot with 5120 chips. TheDL access slot is aligned wih PCCPCH.

The UL PRACH is divided into 15 UL access slots, each slot with

ZTE UMTS Idle Mode and Channel Behavior Feature Guide U9.2

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