Idle Mode Management(ERAN8.1_05)

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Idle Mode Management Feature

Parameter Description

Issue 05

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No part of this document may be reproduced or transmitted in any form or by any means without prior written consent of Huawei Technologies Co., Ltd.

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and other Huawei trademarks are trademarks of Huawei Technologies Co., Ltd.

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Notice

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representations of any kind, either express or implied.

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

Huawei Technologies Co., Ltd.

Address: Huawei Industrial Base

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People's Republic of China Website: http://www.huawei.com

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1 About This Document... 1

1.1 Scope... 1

1.2 Intended Audience...1

1.3 Change History... 2

1.4 Differences Between eNodeB Types... 4

2 Overview... 5

2.1 Introduction... 5 2.2 Benefits...5 2.3 Architecture... 5 2.4 Relate Concepts... 6 2.4.1 PLMN... 6 2.4.2 Access Classes...7 2.4.3 Service Types...8

3 Technical Description...9

3.1 PLMN Selection... 10

3.1.1 PLMN Selection in Automatic Mode...10

3.1.2 PLMN Selection in Manual Mode...11

3.1.3 Roaming...11

3.2 Cell Selection and Reselection... 11

3.2.1 Cell Search...12

3.2.2 Cell Selection...13

3.2.3 Neighboring Cell Priority Handling... 14

3.2.4 Blacklisted Cell Identifying...17

3.2.5 Neighboring Cell Measurement for Cell Reselection...17

3.2.6 Intra-Frequency or Equal-Priority Cell Reselection... 19

3.2.7 Different-Priority Inter-Frequency or Inter-RAT Cell Reselection... 21

3.2.8 Speed-based Cell Reselection...25

3.3 Tracking Area Registration...26

3.3.1 Tracking Area Update...26

3.3.2 Attach/Detach... 27

3.4 Cell Reservation and Access Control... 27

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3.4.2 Access Control...28

3.5 System Information Broadcast... 28

3.5.1 System Information Block Contents...29

3.5.2 System Information Scheduling Periods... 30

3.5.3 System Information Message Update...31

3.6 Paging... 32

3.6.1 Triggering of Paging...32

3.6.2 Paging Mechanism on the Uu Interface... 32

3.6.3 Paging Handling Procedure... 34

4 Related Features...36

4.1 Features Related to LBFD-002009 Broadcast of System Information...36

4.2 Features Related to LBFD-002011 Paging...37

4.3 Features Related to LBFD-00201803 Cell Selection and Re-selection...37

5 Network Impact... 38

5.1 LBFD-002009 Broadcast of System Information... 38

5.2 LBFD-002011 Paging...38

5.3 LBFD-00201803 Cell Selection and Re-selection... 38

6 Engineering Guidelines... 40

6.1 When to Use Idle Mode Management...40

6.2 Required Information... 40 6.3 Planning... 40 6.4 Deployment... 40 6.4.1 Requirements... 40 6.4.2 Data Preparation... 40 6.4.3 Initial Configuration... 62

6.4.3.1 Using the CME to Perform Batch Configuration for Newly Deployed eNodeBs...62

6.4.3.2 Using the CME to Perform Batch Configuration for Existing eNodeBs... 65

6.4.3.3 Using the CME to Perform Single Configuration... 66

6.4.3.4 Using MML Commands...67

6.4.4 Commissioning...68

6.4.5 Activation Observation...69

6.4.6 Reconfiguration... 71

6.4.7 Deactivation...71

6.4.7.1 Using the CME to Perform Batch Configuration... 71

6.4.7.2 Using the CME to Perform Single Configuration... 73

6.4.7.3 Using MML Commands...73 6.5 Performance Monitoring...74 6.6 Parameter Optimization...75 6.7 Troubleshooting... 78

7 Parameters...79

8 Counters... 133

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9 Glossary...137

10 Reference Documents... 138

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1

About This Document

1.1 Scope

This document describes Idle Mode management, including its technical principles, related features, network impact, and engineering guidelines. This document covers the following features:

l LBFD-002009 Broadcast of System Information l LBFD-002011 Paging

l LBFD-00201803 Cell Selection and Re-selection

Any managed objects (MOs), parameters, alarms, or counters described herein correspond to the software release delivered with this document. Any future updates will be described in the product documentation delivered with future software releases.

This document applies only to LTE FDD. Any "LTE" in this document refers to LTE FDD, and "eNodeB" refers to LTE FDD eNodeB.

This document applies to the following types of eNodeBs.

eNodeB Type Model

Macro 3900 series eNodeB

Micro BTS3202E

LampSite DBS3900 LampSite

1.2 Intended Audience

This document is intended for personnel who: l Need to understand the features described herein l Work with Huawei products

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1.3 Change History

This section provides information about the changes in different document versions. There are two types of changes:

l Feature change

Changes in features of a specific product version and parameters of a specified version as well as the affected entities.

l Editorial change

Changes in wording or addition of information and any related parameters affected by editorial changes. Editorial change does not specify the affected entities.

eRAN8.1 05 (2015-12-30)

This issue includes the following changes.

Change Type Description Parameter

Change AffectedEntity

Feature change None None N/A

Editorial change

l Revised the descriptions in

Inter-Frequency or Inter-RAT Measurement.

l Revised the descriptions in 3.2.3 Neighboring Cell Priority Handling.

None

-eRAN8.1 04 (2015-11-03)

Feature change Added descriptions on the problem that an SRLTE UE may miss LTE system information update when listening to CDMA2000 1X paging messages. For details, see 3.5.3 System Information Message Update and 6.6 Parameter Optimization. None Macro/Micro/ LampSite Editorial change None None

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-eRAN8.1 03 (2015-06-30)

Editorial change

Optimized some descriptions. For details, see 3.2.6 Intra-Frequency or Equal-Priority Cell Reselection

and 6.4.3.4 Using MML Commands.

None

-eRAN8.1 02 (2015-04-30)

Editorial change

Optimized some descriptions. For details, see 3.2.2 Cell Selection and

3.2.7 Different-Priority Inter-Frequency or Inter-RAT Cell Reselection.

None

-eRAN8.1 01 (2015-03-23)

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Editorial change

l Modified descriptions about PO subframes. For details, see 3.6.2 Paging Mechanism on the Uu Interface.

l Added descriptions about speed-based cell reselection. For details, see 3.2.8 Speed-based Cell Reselection.

l Modified descriptions about reselection to a high-priority cell. For details, see 3.2.7 Different-Priority Inter-Frequency or Inter-RAT Cell Reselection.

None

-eRAN8.1 Draft A (2015-01-15)

Compared with Issue 03 (2014-12-30) of eRAN7.0, Draft A (2015-01-15) of eRAN8.1 includes the following changes.

Editorial change

l Optimized some descriptions. For details, see Intra-Frequency Measurement in

3.2.5 Neighboring Cell Measurement for Cell Reselection.

l Added information about some parameters. For details, see 6.4.2 Data Preparation.

None

-1.4 Differences Between eNodeB Types

The features described in this document are implemented in the same way on macro, micro, and LampSite eNodeBs.

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2

Overview

2.1 Introduction

In an Evolved Universal Terrestrial Radio Access Network (E-UTRAN), UEs can be either in RRC_CONNECTED or RRC_IDLE mode. UE and RRC are short for user equipment and radio resource control, respectively.

After being powered on, UEs are in RRC_IDLE mode (also known as idle mode) if no RRC connection is established between the UEs and the E-UTRAN.

2.2 Benefits

With idle mode management, the eNodeB sends configurations by broadcasting system information, and accordingly, UEs select suitable cells to camp on. Idle mode management increases the access success rate, improves the quality of service, and ensures that UEs camp on cells with good RX signal levels and qualities.

2.3 Architecture

This document describes idle mode management from the following aspects: l PLMN selection

A UE selects a Public Land Mobile Network (PLMN) and registers on the PLMN. l Cell selection

A UE selects a cell in the chosen PLMN and camps on the cell so that the UE can monitor system information and paging messages to obtain service.

l Cell reselection

When camped on a cell, a UE regularly searches for a better cell according to the cell reselection criteria, for the purpose of correctly receiving system information and successfully initiating services.

l Tracking Area (TA) registration

A UE registers its location with the Evolved Packet Core (EPC) through a TA

registration procedure so that the EPC can page the UE within the TA and request the UE to initiate services.

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l Cell reservation and access control

Cell reservation and access control are two mechanisms for operators to control their networks. In the cell reservation mechanism, specific cells can be reserved for only UEs of special classes (for example, for the network management purpose of operators). In the access control mechanism, the UEs that can initiate calls in a cell are determined on the basis of the classes of the UEs.

l System information broadcast and paging

In system information broadcast, the information such as parameters related to cell selection and reselection is broadcast to UEs through system information over the Broadcast Control Channel (BCCH). In paging, paging messages are used to inform all UEs in a cell of a change in the system information and to carry paging-related

information.

The main activities of UEs in idle mode are PLMN selection, cell selection and reselection, and TA registration. Figure 2-1 shows the relationships between them.

Figure 2-1 Relationships between PLMN selection, cell selection and reselection, and TA registration

2.4 Relate Concepts

2.4.1 PLMN

A PLMN identity consists of a Mobile Country Code (MCC) and a Mobile Network Code (MNC).

EPLMN List

The Equivalent PLMN (EPLMN) list is a list of PLMNs considered as equivalents to Registered PLMNs (RPLMNs) in terms of service provisioning. During PLMN selection, a

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UE preferentially selects a PLMN from the list. The EPLMN list plus RPLMN is sent from the EPC and stored in the UE during an Attach procedure and TA update. An EPLMN list can contain more than one EPLMN.

HPLMN

The Home PLMN (HPLMN) is the PLMN in which the UE is defined.

VPLMN

The Visited PLMN (VPLMN) is the PLMN where the UE is located. A VPLMN can be the HPLMN.

EHPLMN

An Equivalent Home PLMN (EHPLMN) is an equivalent to the HPLMN, and takes

precedence over the HPLMN. The EHPLMN list is stored in the Universal subscriber identity module (USIM) of the UE. During PLMN selection, the UE takes into account both the EHPLMNs and the HPLMN that is extracted from the international mobile subscriber identity (IMSI), and preferentially selects an EHPLMN.

RPLMN

The RPLMN is the PLMN on which the UE has performed a location registration successfully by TA update.

2.4.2 Access Classes

Access classes are applicable to UE access on the radio interface. There are 16 access classes, numbered from 0 to 15. The information about access classes 0 to 9 and 11 to 15 is stored in USIMs, and the information about access class 10 is signaled to UEs through system information broadcast to indicate whether cells allow emergency calls.

l Access classes 0 to 9 are ordinary classes. Each UE is randomly allocated one out of these ten classes. UEs of these classes can obtain service in their HPLMN, EPLMN, and VPLMNs.

l Access classes 11 to 15 are special classes. They are allocated to specific high-priority users. Each UE may be allocated one or more out of the five classes. These special access classes are described as follows:

UEs of access classes 11 and 15 can receive services only in their HPLMN and

EHPLMNs. If the EHPLMN list is absent, access classes 11 and 15 are applicable in the HPLMN only.

– Class 11: for PLMN use – Class 15: for PLMN staff

Access classes 12 to 14 are applicable in the HPLMN and VPLMNs of the home country only.

– Class 12: for security services – Class 13: for public utilities – Class 14: for emergency services

l If access class 10 is barred, UEs of access classes 0 to 9 or UEs without USIMs are not allowed to initiate emergency calls. For UEs of access classes 11 to 15, emergency calls

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are not allowed if both access class 10 and the relevant access class (within the range from 11 to 15) are barred.

2.4.3 Service Types

The services that UEs in idle mode can obtain are categorized into the following types: l Limited service

A UE can initiate only emergency calls in an Acceptable Cell. Such a cell should meet the requirements that the cell is not barred and the cell selection criteria are fulfilled. The UE camps on the Acceptable Cell to obtain Limited service when the cell is part of at least one TA on the list of forbidden TAs for roaming or when the cell does not belong to the RPLMN. For details about the cell selection criteria, see 3.2.2 Cell Selection. l Normal service

A UE obtains normal service in a suitable cell. Such a cell should meet all the following requirements:

– The cell is part of the selected PLMN, the RPLMN, or a PLMN on the EPLMN list. – The cell is part of at least one TA that belongs to a PLMN fulfilling the previous

requirement but is not on the list of forbidden TAs for roaming. For details, see section 3.1 "PLMN selection and roaming" in 3GPP TS 23.122 R10, which was released in March 2011.

– The cell is not barred.

– The cell selection criteria are fulfilled. l Operator service

A UE obtains operator service in a Reserved Cell, which is used by the operator only. In the case of access class 11 or 15 in the HPLMN or an EHPLMN, a UE may consider Reserved Cells as candidates during cell selection or reselection. In other cases, a UE regards Reserved Cells as barred during cell selection or reselection. UEs are not allowed to camp on barred cells.

NOTE

Whether a cell is barred can be set through the CELLACCESS.CellBarred parameter, and the setting is delivered through system information block type 1 (SIB1). Whether a cell is a Reserved Cell can be set through the CELLOP.CellReservedForOp parameter by the operator. This parameter setting is also delivered in SIB1.

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3

Technical Description

To guarantee the access success rate and to shorten the access time, a UE in idle mode selects a cell based on the RX signal level and quality of the measured cells and according to the parameters in the system information. When camping on the cell, the UE regularly searches for a better cell according to the cell reselection criteria, in order to receive system

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3.1 PLMN Selection

Figure 3-1 shows the PLMN selection procedure. When a UE is powered on or recovers from lack of coverage, the UE first selects the last registered PLMN (RPLMN) or a PLMN in the EPLMN list and attempts to register on that PLMN. If the registration on that PLMN is successful, the UE shows the selected PLMN on the display, and can now obtain service from an operator. If the last RPLMN is unavailable or if the registration on that PLMN fails, another PLMN can be automatically or manually selected according to the priorities of PLMNs stored in the USIM. For details about PLMN selection, see section 4.4 in 3GPP TS 23.122 R10, which was released in March 2011.

Figure 3-1 PLMN selection procedure

3.1.1 PLMN Selection in Automatic Mode

When a UE fails to register on its last RPLMN or EPLMN, the UE attempts to select another PLMN. In automatic network selection mode, the UE selects a PLMN in the following order: 1. The EHPLMN with the highest priority if the EHPLMN list is available and contains at

least one EHPLMN, or the HPLMN if the EHPLMN list is blank or unavailable.

2. Each combination of PLMN with radio access technology (RAT) in the "User Controlled PLMN Selector with Access Technology" data file in the USIM, in order of priority. 3. Each combination of PLMN with RAT in the "Operator Controlled PLMN Selector with

Access Technology" data file in the USIM, in order of priority.

4. Other combinations of PLMNs with RATs providing high-quality signals, in a random order. A high-quality signal is defined as the Reference Signal Received Power (RSRP)

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value of a cell in the combination of PLMN with RAT being greater than or equal to -110 dBm.

5. Other combinations of PLMNs with RATs in order of descending RX signal quality. When the UE finds a suitable cell in a PLMN during the preceding procedure, the UE attempts to register on the PLMN. If the registration is successful, the UE camps on the suitable cell; otherwise, the UE tries the next PLMN.

If the registration on none of the PLMNs is successful, the UE enters the Limited service state. If no PLMN is available, the UE cannot obtain any services.

3.1.2 PLMN Selection in Manual Mode

When a UE fails to register on its last RPLMN or EPLMN, the UE attempts to select another PLMN. In manual network selection mode, the UE displays a list of detected PLMNs in the same order as the PLMNs to be selected in automatic network selection mode.

In manual mode, the UE can also try forbidden PLMNs. If the UE succeeds in registering on the selected PLMN, the PLMN is no more a forbidden PLMN to the UE. The forbidden PLMNs are determined by the EPC.

3.1.3 Roaming

When in roaming state, a UE obtains service from a VPLMN that is different from its HPLMN. For example, the UE may obtain service from a PLMN in another country (an international roaming area). When the UE with the roaming service moves out of the coverage area of its HPLMN, the UE can obtain service from another PLMN according to the PLMN information stored in the USIM. The operator determines whether roaming is allowed for a UE.

After the UE registers on a VPLMN by roaming, it periodically searches for its HPLMN and attempts to return to the HPLMN. The time interval between consecutive searches for the HPLMN is defined by the operator and stored in the USIM.

3.2 Cell Selection and Reselection

This section describes the basic feature LBFD-00201803 Cell Selection and Re-selection. After selecting a PLMN, a UE selects a cell in the PLMN to camp on. After camping on the cell, the UE monitors system information, performs measurements on the serving cell and neighboring cells, and selects a better cell to camp on, based on measurement rules and cell reselection criteria.

Before the UE selects a cell to camp on, it performs a cell search procedure. After the UE finds a cell, it performs cell selection or reselection, according to the selection- or reselection-related parameters in the system information or in the RRC Connection Release message.

Figure 3-2 shows the cell selection and reselection procedures. A UE can use one of the following two cell selection procedures: Stored Information Cell Selection and Initial Cell Selection. The Stored Information Cell Selection procedure takes precedence over the Initial Cell Selection procedure. The UE uses the latter procedure only when it fails to find a suitable cell by using the former procedure. For details, see section 5.2.2 "States and state transitions in Idle Mode" in 3GPP TS 36.304 R10, which was released in March 2011.

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Figure 3-2 Cell selection and reselection procedures

3.2.1 Cell Search

Cell search is a procedure in which a UE achieves time and frequency synchronization with a cell, obtains the physical cell identifier (PCI), and learns the RX signal quality and other information about the cell based on the PCI. Before selecting or reselecting a cell, a UE performs a cell search on all carrier frequencies.

In the LTE system, Synchronization Channels (SCHs) are specially used for cell search. There are two types of SCHs: Primary Synchronization Channels (P-SCHs) and Secondary

Synchronization Channels (S-SCHs). The cell search procedure on SCHs is as follows: 1. The UE monitors the P-SCH to achieve clock synchronization with a maximum

synchronization error of 5 ms. The UE determines the cell identity in a cell identity group based on the mapping between cell identities and primary synchronization signals. 2. The UE monitors the S-SCH to achieve frame synchronization, that is, time

synchronization with the cell. Cell identity groups have a one-to-one relationship with secondary synchronization signals. Therefore, the UE acquires the number of the cell identity group to which the cell identity belongs by monitoring the S-SCH.

3. The UE determines the PCI based on the cell identity and the cell identity group number. 4. The UE monitors the downlink reference signal to acquire the RX signal quality in the

cell.

5. The UE monitors the Broadcast Channel (BCH) to acquire other information about the cell.

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NOTE

In an E-UTRAN, PCIs are grouped to reduce the times of correlation detection. Each group consists of three cell identities.

3.2.2 Cell Selection

When a UE transits from the connected mode to the idle mode or after it selects a PLMN, the UE must select a cell to camp on.

When the UE transits from the connected mode to the idle mode, it first attempts to select the last cell that it camped on in connected mode or select a suitable cell on the frequency that is allocated through the RRC Connection Release message. If such a cell is not available, the UE attempts to find a suitable cell by performing the Stored Information Cell Selection procedure. If the UE fails to find a suitable cell, the UE performs the Initial Cell Selection procedure.

Stored Information Cell Selection

The Stored Information Cell Selection procedure requires stored information on carrier frequencies and information on cell parameters. The information is obtained from previously received measurement control information elements or from previously detected SI messages of cells. This information can help speed up cell selection.

The Stored Information Cell Selection procedure is as follows: On the known carrier

frequency, the UE searches for a suitable cell. If the UE finds a suitable cell, it selects that cell to camp on. If the UE fails to find a suitable cell, it initiates the Initial Cell Selection

procedure.

Initial Cell Selection

The Initial Cell Selection procedure does not require that the UE know in advance which carrier is an E-UTRAN frequency.

The Initial Cell Selection procedure is as follows: The UE scans all RF channels in the E-UTRAN bands according to its capabilities in order to find a suitable cell. On each carrier frequency, the UE searches for the strongest cell only. If the UE finds a suitable cell, it selects that cell to camp on. If the UE fails to find a suitable cell, it selects an Acceptable Cell to camp on.

Cell Selection Criteria

During cell selection, a UE selects an E-UTRAN cell that meets cell selection criteria. A UE selects an E-UTRAN cell to camp on when both Srxlev and Squal are greater than zero. Where:

Srxlev = Qrxlevmeas - (Qrxlevmin + Qrxlevminoffset) - Pcompensation Squal = Qqualmeas - (QqualMin + QqualMinOffset)

l The variables in the preceding formulas are described as follows: Qrxlevmeas is the measured RX signal level (RSRP value) of the cell.

l Qrxlevmin is the lowest cell RX signal level. It is broadcast in the SIB1 and set by the

CELLSEL.QRxLevMin parameter.

l Qrxlevminoffset is the offset to Qrxlevmin. It is broadcast in the SIB1 and set by the

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attempts to camp on a cell in a higher-priority PLMN. That is, when camped on a cell in a VPLMN, the UE considers this offset parameter, which was delivered by the cell in the higher-priority PLMN, in the Srxlev evaluation during periodic cell reselection.

l Pcompensation is the result of the function: max (PMax - UE Maximum Output Power,

0).

l PMax is the maximum transmit power that the UE can apply to uplink transmission. It is

broadcast in the SIB1 and set by the CELL.UePowerMax parameter.

l UE Maximum Output Power is the maximum output power that the UE can physically

achieve. It is unconfigurable on the network side.

l Qqualmeas is the measured RX signal quality (RSRQ value) of the cell.

l QqualMin is the lowest cell RX signal quality required for the cell to become a suitable

cell. It is broadcast in the SIB1 and set by the CELLSEL.QQualMin parameter. The CELLRESEL.ThrshServLowQCfgInd parameter controls whether to broadcast

QqualMin in SIB1. For details, see descriptions about SystemInformationBlockType1 in

section 6.2.2 of 3GPP TS 36.331 R10, which was released in March 2011.

l QqualMinOffset is the offset to QqualMin. It is broadcast in the SIB1 and set by the

CELLSEL.QQualMinOffset parameter. The UE camped on a cell in a VPLMN considers this offset parameter when it attempts to camp on a cell in a higher-priority PLMN during periodic cell reselection. The cell in the higher-priority PLMN delivers the value of this parameter to the UE for the Squal evaluation.

3.2.3 Neighboring Cell Priority Handling

After having camped on a cell, a UE may attempt to reselect to, and then camp on another cell. Before cell reselection, the UE is required to measure the signal strength of certain neighboring cells and evaluate each of them by using the criteria that are suitable according to the priority of the neighboring cell, that is, the priority of the frequency on which the

neighboring cell operates.

During measurement and implementation of cell reselection, the UE needs to obtain the priorities of neighboring frequencies. Note that any two RATs must have non-overlapping priorities of frequencies. During the evaluation for reselection to an intra-frequency

neighboring cell, the UE ignores the priority of the target frequency because cells that work on the same frequency have the same priority.

The priorities for E-UTRAN frequencies and inter-RAT frequencies include common priorities and dedicated priorities.

Common Priority

The absolute priority of the serving frequency is specified by the CellResel.CellReselPriority parameter and broadcast in system information block type 3 (SIB3).

The priority of the neighboring E-UTRAN frequency is specified by

EutranInterNFreq.CellReselPriority and broadcast in SIB5. A maximum of 8 neighboring E-UTRAN frequencies can be broadcast.

The priority of the neighboring UTRAN frequency is specified by

UtranNFreq.CellReselPriority and broadcast in SIB6. A maximum of 16 neighboring UTRAN frequencies can be broadcast.

The priority of the neighboring GERAN frequency is specified by

GeranNfreqGroup.CellReselPriority and broadcast in SIB7. A maximum of 16 neighboring GERAN frequency groups can be broadcast.

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The absolute priority of a neighboring CDMA2000 frequency is specified by Cdma2000BandClass.Cdma20001XrttCellReselPri and

Cdma2000BandClass.Cdma2000HrpdCellReselPri and broadcast in SIB8.

Dedicated Priority

During release of UE radio resources, the IdleModeMobilityControlInfo (IMMCI) IE in the RRC Connection Release message delivers the radio resources for each UE. A maximum of 8 neighboring E-TRAN frequencies, 16 neighboring UTRAN frequencies, and 16 neighboring GERAN frequency groups can be delivered for each UE.

Cell reselection dedicated priorities include dedicated SPID priorities and operator-specific dedicated priorities.

l Dedicated SPID priority: Specifies a dedicated cell reselection priority using the SPID. A dedicated SPID priority can be either a public SPID priority or an operator-based SPID priority. The former refers to an SPID priority configured not based on PLMN, and the latter refers to an SPID priority configured based on the PLMN of the serving cell. For details about dedicated SPID priorities, see descriptions of LOFD-00105401 Camp & Handover Based on SPID in Flexible User Steering Feature Parameter Description. In the event of networking sharing, the eNodeB use LOFD-001133Multi Operators SPID Policy to implement the operator-specific SPID dedicated priority function for cell reselection. Specifically, operators sharing the same eNodeB can select their respective SPID value ranges, without negotiating with each other, and the shared eNodeB allows users of different operators to use the same SPID for different cell reselection dedicated priority policies. For details, see RAN Sharing Feature Parameter Description.

l Operator-specific dedicated priority

– Dedicated priority based on home operator of an adjacent frequency: Specifies a dedicated cell reselection priority based on the operator to which an adjacent frequency belongs.

In RAN Sharing scenarios, the dedicated priorities of E-UTRAN, UTRAN, and GERAN frequencies are specified by EutranNFreqRanShare.CellReselPriority, UtranRanShare.CellReselPriority, and GeranRanShare.CellReselPriority, respectively, for different PLMNs.

– Dedicated priority based on home operator of the serving cell: Specifies a dedicated cell reselection priority based on the PLMN ID of the serving cell. The priorities are specified by EutranNFreqSCellOp.CellReselDediPri,

UtranNFreqSCellOp.CellReselDediPri, GeranNFGroupSCellOp.CellReselDediPri,

CDMA2000BCSCELLOP.Cdma1XrttCellReselDediPri, and CDMA2000BCSCELLOP.HrpdCellReselDediPri.

Both dedicated priority based on home operator of an adjacent frequency and dedicated priority based on home operator of the serving cell are dedicated operator priorities. Only one type can be used at a time.

The eNodeB preferentially uses SPID dedicated priorities when determining the dedicated frequency priorities to carry in the RRC Connection Release message. If no SPID priority is configured for the UE, the eNodeB uses the dedicated frequency priorities of operators configured in the EutranNFreqRanShare, UtranRanShare, and GeranRanShare MOs, or the frequency priorities of UE-homed operators configured in the EutranNFreqSCellOp, UtranNFreqSCellOp, GeranNFGroupSCellOp, and Cdma2000BcSCellOp MOs. If no dedicated priority of operators is configured, the eNodeB does not carry dedicated frequency priorities in the RRC Connection Release message. Here are the exceptions:

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l For a CA UE, when the idle-mode PCC anchoring function takes effect, the eNodeB still carries the dedicated frequency priorities generated by this function in the RRC

Connection Release message, if no SPID dedicated priority or dedicated priority of operators is configured. For details about the idle-mode PCC anchoring function, see

Carrier Aggregation Feature Parameter Description.

l For a UE release due to system overload, MME overload, or S1-interface faults, even when the eNodeB does not use any of the preceding dedicated priorities, the eNodeB uses the public priority of the serving frequency as the dedicated priority of a

neighboring frequency and carries the priority in the RRC Connection Release message, if the public priority of the neighboring frequency is lower than the public priority of the serving frequency.

When the eNodeB determines the list of frequency priorities to carry in the RRC Connection Release message, it performs filtering on these frequencies according to UE capabilities and the target PLMN.

l UE capability-based frequency filtering

– If the eNodeB has obtained UE capabilities, it filters out frequencies that UEs do not support based on systems supported by UEs and UE frequency capabilities. – If the eNodeB has not obtained UE capabilities, it checks the value of

CellAlgoSwitch.ReselecPriAdaptSwitch and determines the cause value of RRC access request.

If CellAlgoSwitch.ReselecPriAdaptSwitch is set to ON(On) and the cause value of RRC access request is mo-Signalling (such as TAU accept/reject and attach reject), and the S1 release is initiated by the MME with the cause value NAS, the eNodeB considers that UEs support all frequencies in the priority list and filtering is not required.

Otherwise, the eNodeB considers that UEs support only frequencies of the serving cell. In this case, if frequencies of the serving cell are included in the frequency list, they are reserved and other frequencies are filtered out. If frequencies of the serving cell are not included in the frequency list, the eNodeB does not deliver the IMMCI IE.

l Target PLMN-based filtering

– If all home PLMNs of external cells under the frequency are not included in the target PLMN list, the eNodeB filters out the frequency.

– If no external cells are configured on the frequency (no PLMN information of external cells), the eNodeB fails to obtain PLMN attributes of the frequency and filters out the frequency.

The eNodeB includes filtered frequencies in the IMMCI IE and delivers it to UEs. During cell reselection, when a UE is camped on a suitable cell, the UE ignores all the absolute priorities provided in system information if dedicated priorities are assigned through dedicated signaling. If the UE acquires the priorities of other frequencies but no priority of the serving frequency, the UE regards the priority of the serving frequency as the lowest.

During cell reselection, when a UE is camped on an Acceptable Cell, the UE uses only the absolute priorities provided in system information. The UE only stores the information about the dedicated priorities but does not use it for cell reselection even when dedicated priorities are available.

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l The NAS signals the AS to perform PLMN selection. l The UE enters the connected mode.

l The validity time (specified by T320) of the dedicated priority expires.

T320 and the dedicated priority are sent to the UE in the RRC Connection Release message. The eNodeB determines the value of T320 in the following two ways:

l If the dedicated priority is obtained through the UE's SPID mapping or the PCC anchoring function, the value of T320 is always 180 minutes.

l If the dedicated priority is obtained through other means, for an RRC release due to load balancing, T320 is specified by the RrcConnStateTimer.T320ForLoadBalance parameter for an RRC connection release due to load balancing, or by the

RrcConnStateTimer.T320ForOther parameter during an RRC connection release due to other reasons.

For details about T320, see section 7.3 in 3GPP TS 36.331 V10.1.0 (2011-03).

3.2.4 Blacklisted Cell Identifying

During cell reselection, UEs are not allowed to measure or reselect the blacklisted cells of the serving cell. Blacklisted cells are classified into intra-frequency and inter-frequency

blacklisted cells.

l Information about intra-frequency blacklisted cells is delivered in

IntraFreqBlackCellList of the SIB4 and is excluded from IntraFreqNeighCellList of the

SIB4.

l Information about inter-frequency blacklisted cells is delivered in InterFreqBlackCellList of the SIB5 and is excluded from InterFreqNeighCellList of the SIB5.

UEs identify blacklisted cells by PCIs.

An intra-frequency blacklist can be configured by adding an IntraFreqBlkCell MO. Cells in this blacklist are indicated by a starting PCI (set by INTRAFREQBLKCELL.PhyCellId) and the number of consecutive PCIs from the starting PCI onwards (set by

INTRAFREQBLKCELL.PhyCellIdRange).

An inter-frequency blacklist can be configured by adding an INTERFREQBLKCELL MO. INTERFREQBLKCELL.DlEarfcn specifies the downlink EARFCN corresponding to the neighboring E-UTRAN frequency, INTERFREQBLKCELL.PhyCellId specifies a starting PCI, and INTERFREQBLKCELL.PhyCellIdRangespecifies the number of consecutive PCIs from the starting PCI onwards.

3.2.5 Neighboring Cell Measurement for Cell Reselection

During cell reselection, a UE performs measurements of neighboring cells based on the RX signal level and quality of the serving cell and frequency priorities of the neighboring cells. The UE measures only the neighboring frequencies broadcast in the system information and the neighboring frequency whose priority information is carried in the RRC Connection Release message.

Intra-Frequency Measurement

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l The UE does not perform intra-frequency measurements if the Srxlev and Squal values of the serving cell are greater than S_IntraSearchP and S_IntraSearchQ, respectively. The UE performs intra-frequency measurements if the Srxlev or Squal value of the serving cell is not greater than SIntraSearchP or SIntraSearchQ, respectively.

– When only s-IntraSearch (configured in CELLRESEL.SIntraSearch) is broadcast in SIB3, the UE uses the value of s-IntraSearch as that for SIntraSearchP.

– When both s-IntraSearch and s-IntraSearchP (configured in

CELLRESEL.SIntraSearch) are broadcast in SIB3, or when only s-IntraSearchP is broadcast in SIB3, the UE takes the value of s-IntraSearchP as that for

SIntraSearchP.

– When neither s-IntraSearch nor s-IntraSearchP are broadcast in SIB3, the UE uses the default settings of SIntraSearchP (default value: infinite) and SIntraSearchQ (default value: 0). In this situation, the UE performs intra-frequency measurements, regardless of the signal quality of the serving cell.

– When s-IntraSearchQ (configured in CELLRESEL.SIntraSearchQ) is broadcast in SIB3, the UE uses the value of s-IntraSearchQ as that for SIntraSearchQ.

l If CELLRESEL.SIntraSearchCfgInd is set to NOT_CFG, s-IntraSearch is not broadcast in SIB3; if CELLRESEL.QQualMinCfgInd is set to NOT_CFG,

s-IntraSearchP and s-IntraSearchQ are not broadcast in SIB3.

For details about how to calculate the Srxlev and Squal values, see 3.2.2 Cell Selection.

Inter-Frequency or Inter-RAT Measurement

To trigger inter-frequency or inter-RAT measurements, the following rules apply:

l The UE always performs measurements on inter-frequency or inter-RAT neighboring cells regardless of the RX signal level or quality of the serving cell if the priorities of the neighboring frequencies are higher than the priority of the serving frequency.

l If the priorities of neighboring E-UTRA frequencies are lower than or equal to the priority of the serving frequency, or if the priorities of inter-RAT neighboring frequencies are lower than the priority of the serving frequency, the UE determines whether to start the corresponding measurements according to the following rules:

– The UE does not perform inter-frequency or inter-RAT measurements if the Srxlev and Squal values of the serving cell are greater than SnonIntraSearchP and

SnonIntraSearchQ, respectively. SnonIntraSearchP indicates the Srxlev threshold for triggering inter-frequency or inter-RAT measurements. S_{nonIntraSearchQ} indicates the

Squal threshold for triggering inter-frequency or inter-RAT measurements.

– The UE performs inter-frequency or inter-RAT measurements if the Srxlev or Squal value of the serving cell is not greater than S_{nonIntraSearchP} or S_{nonIntraSearchQ}, respectively.

The following table provides reference for determining the values of S_{nonIntraSearchP} and S_{nonIntraSearchQ}:

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CELLRESEL. SNonIntraSe archCfgInd CELLRESE L.QQualMi nCfgInd IEs Broadcast in SIB3 SnonIntraSearchP Value SnonIntraSearch Q Value NOT_CFG(N ot configure) CFG(Config ure) s-NonIntraSea rchP and s-NonIntraSea rchQ s-NonIntraSearc hP s-NonIntraSearc hQ CFG(Configu re) NOT_CFG( Not configure) s-NonIntraSea rch s-NonIntraSearc h 0 dB NOT_CFG(No t Configure)(1) NOT_CFG( Not Configure)(1) N/A(1) _infinity(1) _{0 dB}(1) CFG(Configu re) CFG(Config ure) s-NonIntraSea rchP, s-NonIntraSea rchQ, and s-NonIntraSea rch s-NonIntraSearc hP s-NonIntraSearc hQ

Both s-NonIntraSearch and s-NonIntraSearchP broadcast in SI are specified by the CELLRESEL.SNonIntraSearch parameter, and s-NonIntraSearchQ is specified by the CELLRESEL.SNonIntraSearchQ parameter.

NOTE

(1)_{: UEs measure both inter-frequency and inter-RAT cells, regardless of whether the signal quality}

in the serving cell is good.

3.2.6 Intra-Frequency or Equal-Priority Cell Reselection

A UE uses the cell reselection criteria to reselect an intra-frequency or equal-priority inter-frequency cell. The UE evaluates the neighboring cell using the cell reselection criteria only when the cell meets the cell selection criteria, which is described in "Cell Selection Criteria". The following parameters broadcast in the SIB3 are used for calculating the Srxlev and Squal values of intra-frequency neighboring cells:

CELLRESEL.QRxLevMin parameter.

l PMax is the maximum transmit power that the UE can apply to uplink transmission in

the neighboring cell. It is broadcast in the SIB3 and set by the CELLRESEL.PMax parameter.

l Qqualmin is the lowest cell RX signal quality. It is broadcast in the SIB3 and set by the

CELLRESEL.QQualMin parameter.

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The following parameters broadcast in the SIB5 are used for calculating the Srxlev and Squal values of inter-frequency neighboring cells:

EUTRANINTERNFREQ.QRxLevMin parameter.

l PMax is the maximum transmit power that the UE can apply to uplink transmission in

the neighboring cell. It is broadcast in the SIB5 and set by the EUTRANINTERNFREQ.PMax parameter.

l Qqualmin is the lowest cell RX signal quality. It is broadcast in the SIB5 and set by the

EUTRANINTERNFREQ.QQualMin parameter.

The cell-ranking criteria R_s for the serving cell and R_n for neighboring cells are defined as follows:

R_s = Qmeas,s + Qhyst R_n = Qmeas,n - Qoffset where:

l Qmeas,s is the measured RSRP value of the serving cell.

l Qhyst is the reselection hysteresis for the serving cell. It is broadcast in the SIB3 and set

by the CELLRESEL.Qhyst parameter.

l Qmeas,n is the measured RSRP value of the neighboring cell.

l Qoffset is equal to q-OffsetCell broadcast in the SIB4 for intra-frequency neighboring

cells or q-OffsetCell plus q-OffsetFreq broadcast in the SIB5 for inter-frequency neighboring cells. If OffsetCell is not broadcast in the SIB4 or SIB5, the UE sets

q-OffsetCell to 0. q-q-OffsetCell in the SIB4 is set by the

EUTRANINTRAFREQNCELL.CellQoffset parameter. q-OffsetCell in the SIB5 is set by the EUTRANINTERFREQNCELL.CellQoffset parameter and q-OffsetFreq is set by the EUTRANINTERNFREQ.QoffsetFreq parameter.

NOTE

The SIB4 and SIB5 broadcast a maximum of 16 intra- and inter-frequency neighboring cells of a frequency, respectively. The eNodeB supports a maximum of 256 intra- and inter-frequency neighboring cells in total. When more than 16 intra- or inter-frequency neighboring cells are configured, the eNodeB selects 16 intra- and inter-frequency neighboring cells that are to be broadcast in the SIB4 or SIB5 by using the following rules in sequence:

1. Neighboring cells whose EUTRANINTRAFREQNCELL.CellQoffset and

EUTRANINTERFREQNCELL.CellQoffset are set to 0 are not broadcast.

2. Neighboring cells whose EUTRANINTRAFREQNCELL.CellMeasPriority and

EUTRANINTERFREQNCELL.CellMeasPriority are set to HIGH are preferentially

broadcast.

3. Neighboring cells whose EUTRANINTRAFREQNCELL.CellQoffset and

EUTRANINTERFREQNCELL.CellQoffset values are greater than those of other

neighboring cells are broadcast.

4. If less than 16 neighboring cells are to be broadcast when the preceding rules are applied, the eNodeB supplements the SIB4 or SIB5 with the neighboring cells whose

EUTRANINTRAFREQNCELL.CellMeasPriority and

EUTRANINTERFREQNCELL.CellMeasPriority are set to LOW and the CellQoffset

value is greater than that of other neighboring cells.

According to the cell reselection criteria, the UE selects a neighboring cell with the greatest R_n value and reselects the neighboring cell only if both the following conditions are met: l The new cell is ranked higher than the serving cell during the cell reselection time. The

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set by the CELLRESEL.TreselEutran parameter. The cell reselection time for an inter-frequency neighboring cell is broadcast in the SIB5 and set by the

EUTRANINTERNFREQ.EutranReselTime parameter. l The UE has camped on the serving cell for more than 1 second.

During cell reselection, the UE needs to check whether access to a cell is allowed according to the Information Element (IE) cellAccessRelatedInfo in the SIB1 sent from the cell. If the cell is barred, it must be excluded from the candidate list. If the cell is unsuitable because it is part of the list of forbidden TAs for roaming or it does not belong to the RPLMN or an EPLMN, the UE does not consider this cell and other cells on the same frequency as candidates for reselection for a maximum of 300 seconds.

3.2.7 Different-Priority Inter-Frequency or Inter-RAT Cell

Reselection

Reselection to a different-priority inter-frequency cell or an inter-RAT cell can be classified into reselection to a higher-priority cell and reselection to a lower-priority cell.

Inter-RAT Cell Selection Criteria

During reselection to an inter-frequency neighboring cell or an inter-RAT neighboring cell, the Srxlev and Squal values of inter-RAT neighboring cells need to be calculated. The calculation method is as follows:

l Inter-frequency neighboring cell

See "3.2.6 Intra-Frequency or Equal-Priority Cell Reselection." l Neighboring UTRAN cell

Srxlev = Qrxlevmeas - (Qrxlevmin + Qrxlevminoffset) - Pcompensation Squal = Qqualmeas - (Qqualmin + Qqualminoffset)

Pcompensation = max(UE_TXPWR_MAX_RACH - P_MAX, 0)

Qrxlevmeas is the measured RX signal level of the neighboring UTRAN cell. Qqualmeas is the measured RX signal quality of the neighboring UTRAN cell.

The values of the preceding parameters are broadcast in the SIB6 from the E-UTRAN when the UE implements reselection estimation on a neighboring UTRAN cell.

Qrxlevmin is set by the UTRANNFREQ.QRxLevMin parameter. Qqualmin is set by the UTRANNFREQ.Qqualmin parameter.

UE_TXPWR_MAX_RACH is set by the UTRANNFREQ.PmaxUtran parameter. P_MAX is the maximum output power that the UE can physically provide. It is unconfigurable on the network side.

Values of Qrxlevminoffset and Qqualminoffset are obtained from UTRAN system information. For details, see section 5.2.3.1 "UTRA case" in 3GPP TS 25.304 R10, which was released in March 2011.

l Neighboring GERAN cell

Srxlev = Qrxlevmeas - Qrxlevmin - Pcompensation

Qrxlevmeas is the measured RX signal level of the neighboring GERAN cell.

Pcompensation = max(MS_TXPWR_MAX_CCH - P, 0)

The values of the preceding parameters are broadcast in the SIB7 from the E-UTRAN when the UE implements reselection estimation on a neighboring GERAN cell.

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Qrxlevmin is set by the GERANNFREQGROUP.QRxLevMin parameter.

MS_TXPWR_MAX_CCH is set by the GERANNFREQGROUP.PmaxGeran parameter.

P is the maximum output power that the UE can physically provide.

It is unconfigurable on the network side. For details, see section 3.6 "Radio constraints" in 3GPP TS 43.022 R10, which was released in March 2011.

l Neighboring CDMA2000 cell

Ec/Io is the measured RX signal quality of the neighboring CDMA2000 cell. For details, see 3GPP2 C.S0005-A.

Reselection to a Higher-Priority Cell

If CELLRESEL.ThrshServLowQCfgInd is set to CFG(Configure), the SIB3 contains

threshServingLowQ (set by CELLRESEL.ThrshServLowQ). In this situation, a UE reselects

to a higher-priority inter-frequency or inter-RAT neighboring cell when all the following conditions are met:

l The neighboring cell has one of the following measurement results: – For a neighboring E-UTRAN cell

The Squal value of the evaluated neighboring E-UTRAN cell is always greater than the value of threshX-High broadcast in the SIB5 during the inter-frequency

neighboring cell reselection time specified in the SIB5. The time is set by EUTRANINTERNFREQ.EutranReselTime and threshX-HighQ is set by EUTRANINTERNFREQ.ThreshXHighQ. For details about how to calculate the

Squal value, see "Cell Selection Criteria."

– For a neighboring UTRAN FDD cell

The Squal value of the evaluated neighboring UTRAN FDD cell is always greater than the value of threshX-HighQ broadcast in the SIB6 during the neighboring UTRAN FDD cell reselection time specified in the SIB6. The time is set by CELLRESELUTRAN.TreselUtran and threshX-HighQ is set by

UTRANNFREQ.ThreshXHighQ. – For a neighboring UTRAN TDD cell

The Srxlev value of the evaluated neighboring UTRAN cell is always greater than the value of threshX-High broadcast in the SIB6 during the neighboring UTRAN TDD cell reselection time specified in the SIB6. The time is set by

CELLRESELUTRAN.TreselUtran and threshX-High is set by UTRANNFREQ.ThreshXHigh.

– For a neighboring GERAN cell

The Srxlev value of the evaluated neighboring GERAN cell is always greater than the value of threshX-High broadcast in the SIB7 during the neighboring GERAN cell reselection time specified in the SIB7. The time is set by

CELLRESELGERAN.TReselGeran and threshX-High is set by GERANNFREQGROUP.ThreshXHigh.

– For a neighboring CDMA2000 cell

The Srxlev value of the evaluated neighboring CDMA2000 cell is always greater than the value of threshX-High broadcast in the SIB8 during the neighboring

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CDMA2000 cell reselection time specified in the SIB8. The time is set by CELLRESELCDMA2000.Cdma1XrttTreselection and

CELLRESELCDMA2000.TreselectionHrpd; threshX-High is set by CDMA2000BANDCLASS.Cdma20001XrttThreshXHigh and CDMA2000BANDCLASS.Cdma2000HrpdThreshXHigh. l The UE has camped on the serving cell for more than 1 second.

If CELLRESEL.ThrshServLowQCfgInd is set to NOT_CFG(Not configure), the SIB3 does not contain threshServingLowQ. In this situation, a UE reselects to a higher-priority inter-frequency or inter-RAT neighboring cell when all the following conditions are met: l The neighboring cell has one of the following measurement results:

– For a neighboring E-UTRAN cell

The Srxlev value of the evaluated neighboring E-UTRAN cell is always greater than the value of threshX-High broadcast in the SIB5 during the inter-frequency

neighboring cell reselection time specified in the SIB5. The time is set by EUTRANINTERNFREQ.EutranReselTime and threshX-High is set by EUTRANINTERNFREQ.ThreshXhigh. For details about how to calculate the

Srxlev value, see "Cell Selection Criteria."

– For a neighboring UTRAN cell

The Srxlev value of the evaluated neighboring UTRAN cell is always greater than the value of threshX-High broadcast in the SIB6 during the neighboring UTRAN cell reselection time specified in the SIB6. The time is set by

CELLRESELUTRAN.TreselUtran and threshX-High is set by UTRANNFREQ.ThreshXHigh.

The Srxlev value of the evaluated neighboring GERAN cell is always greater than the value of threshX-High broadcast in the SIB7 during the neighboring GERAN cell reselection time specified in the SIB7. The time is set by

CELLRESELGERAN.TReselGeran and threshX-High is set by GERANNFREQGROUP.ThreshXHigh.

The Srxlev value of the evaluated neighboring CDMA2000 cell is always greater than the value of threshX-High broadcast in the SIB8 during the neighboring CDMA2000 cell reselection time specified in the SIB8. The time is set by CELLRESELCDMA2000.Cdma1XrttTreselection and

CELLRESELCDMA2000.TreselectionHrpd; threshX-High is set by CDMA2000BANDCLASS.Cdma20001XrttThreshXHigh and CDMA2000BANDCLASS.Cdma2000HrpdThreshXHigh. l The UE has camped on the serving cell for more than 1 second.

If the highest ranked cell is unsuitable for a UE because it is included in a roaming-forbidden TA or because it does not belong to the RPLMN or an EPLMN, the UE does not consider this cell as a candidate for reselection for a maximum of 300 seconds.

Reselection to a Lower-Priority Cell

If CELLRESEL.ThrshServLowQCfgInd is set to CFG(Configure), the SIB3 contains

threshServingLowQ (set by CELLRESEL.ThrshServLowQ). In this situation, a UE reselects

to a lower-priority inter-frequency or inter-RAT neighboring cell when all the following conditions are met:

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l No higher-priority inter-frequency or inter-RAT neighboring cell meets the cell reselection criteria.

During the inter-frequency neighboring cell reselection time specified in the SIB5, the Squal value of the serving cell is always less than the value of

threshServingLowQ broadcast in the SIB3, and the Squal value of the evaluated

neighboring E-UTRAN cell is always greater than the value of threshX-LowQ broadcast in the SIB5. The time is set by

EUTRANINTERNFREQ.EutranReselTime and threshX-LowQ is set by EUTRANINTERNFREQ.ThreshXlowQ. For details about how to calculate the

Squal value, see "Cell Selection Criteria."

– For a neighboring UTRAN FDD cell

During the neighboring UTRAN cell reselection time specified in the SIB6, the

Squal value of the serving cell is always less than the value of threshServingLowQ

broadcast in the SIB3, and the Squal value of the evaluated neighboring UTRAN cell is always greater than the value of threshX-LowQ broadcast in the SIB6. The time is set by CELLRESELUTRAN.TreselUtran and threshX-LowQ is set by UTRANNFREQ.ThreshXLowQ.

– For a neighboring UTRAN TDD cell

broadcast in the SIB3, and the Squal value of the evaluated neighboring UTRAN cell is always greater than the value of threshX-LowQ broadcast in the SIB6. The time is set by CELLRESELUTRAN.TreselUtran and threshX-LowQ is set by UTRANNFREQ.ThreshXLow.

During the neighboring GERAN cell reselection time specified in the SIB7, the

broadcast in the SIB3, and the Srxlev value of the evaluated neighboring GERAN cell is always greater than the value of threshX-Low broadcast in the SIB7. The time is set by CELLRESELGERAN.TReselGeran and threshX-Low is set by

GERANNFREQGROUP.ThreshXlow. – For a neighboring CDMA2000 cell

During the neighboring CDMA2000 cell reselection time specified in the SIB8, the

broadcast in the SIB3, and the Srxlev value of the evaluated neighboring

CDMA2000 cell is always greater than the value of threshX-Low broadcast in the SIB8. The time is set by CELLRESELCDMA2000.Cdma1XrttTreselection and CELLRESELCDMA2000.TreselectionHrpd; threshX-Low is set by

CDMA2000BANDCLASS.Cdma20001XrttThreshXLow and CDMA2000BANDCLASS.Cdma2000HrpdThreshXLow. l The UE has camped on the serving cell for more than 1 second.

If CELLRESEL.ThrshServLowQCfgInd is set to NOT_CFG(Not configure), the SIB3 does not contain threshServingLowQ. In this situation, a UE reselects to a lower-priority inter-frequency or inter-RAT neighboring cell when all the following conditions are met:

l No higher-priority inter-frequency or inter-RAT neighboring cell meets the cell reselection criteria.

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During the inter-frequency neighboring cell reselection time specified in the SIB5, the Srxlev value of the serving cell is always less than the value of

threshServingLow broadcast in the SIB3, and the Srxlev value of the evaluated

neighboring E-UTRAN cell is always greater than the value of threshX-Low broadcast in the SIB5. The time is set by

EUTRANINTERNFREQ.EutranReselTime, threshServingLow is set by CELLRESEL.ThrshServLow, and threshX-Low is set by

EUTRANINTERNFREQ.ThreshXlow. For details about how to calculate the

Srxlev value, see "Cell Selection Criteria."

– For a neighboring UTRAN cell

Srxlev value of the serving cell is always less than the value of threshServingLow

broadcast in the SIB3, and the Srxlev value of the evaluated neighboring UTRAN cell is always greater than the value of threshX-Low broadcast in the SIB6. The time is set by CELLRESELUTRAN.TreselUtran, threshServingLow is set by

CELLRESEL.ThrshServLow, and threshX-Low is set by UTRANNFREQ.ThreshXLow.

During the neighboring GERAN cell reselection time specified in the SIB7, the

broadcast in the SIB3, and the Srxlev value of the evaluated neighboring GERAN cell is always greater than the value of threshX-Low broadcast in the SIB7. The time is set by CELLRESELGERAN.TReselGeran, threshServingLow is set by

CELLRESEL.ThrshServLow, and threshX-Low is set by GERANNFREQGROUP.ThreshXLow.

During the neighboring CDMA2000 cell reselection time specified in the SIB8, the

broadcast in the SIB3, and the Srxlev value of the evaluated neighboring

CDMA2000 cell is always greater than the value of threshX-Low broadcast in the SIB8. The time is set by CELLRESELCDMA2000.Cdma1XrttTreselection and CELLRESELCDMA2000.TreselectionHrpd; threshServingLow is set by CELLRESEL.ThrshServLow; threshX-Low is set by

CDMA2000BANDCLASS.Cdma20001XrttThreshXLow and CDMA2000BANDCLASS.Cdma2000HrpdThreshXLow. l The UE has camped on the serving cell for more than 1 second.

3.2.8 Speed-based Cell Reselection

UE movement is classified, by speed, into the following categories: normal-speed, medium-speed, and high-speed. A UE may start at normal speed and then accelerate. When the UE is at medium or high speed, it fast reselects cells. In such a case, the related cell reselection parameters must be adjusted accordingly. These parameters are configurable only when CellResel.SpeedDepReselCfgInd is set to CFG(Configure).

A UE determines its speed based on the system information broadcast by the eNodeB. The details are as follows:

l A UE determines that it is moving at a normal speed when the following conditions are met:

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– Within the t-Evaluation period (specified by CellResel.TEvaluation), the number of reselected cells is less than or equal to both n-CellChangeMedium (specified by CellResel.NCellChangeMedium) and n-CellChangeHigh (specified by

CellResel.NCellChangeHigh).

– Within the t-HystNormal period (specified by CellResel.THystNormal), the number of reselected cells is less than or equal to both CellChangeMedium and n-CellChangeHigh.

l A UE determines that it is moving at a medium speed when the number of reselected cells is greater than n-CellChangeMedium but less than or equal to n-CellChangeHigh within the t-Evaluation period.

l A UE determines that it is moving at a high speed when the number of reselected cells is greater than n- CellChangeHigh within the t-Evaluation period.

NOTE

If a UE repeatedly selects a cell, the cell is counted only once into the number of reselected cells. Cell reselection conditions vary with the UE speed. The details are as follows:

l Normal-speed UEs: The cell reselection time is equal to t-ReselectionEUTRA (specified by CellResel.TreselEutran) broadcast in system information, and the reselection hysteresis for the serving cell is equal to q-Hyst (specified by CellResel.Qhyst). l Medium-speed UEs: The cell reselection time is equal to

t-ReselectionEUTRA*t-ReselectionEUTRA-SF.sf-Medium (specified by CellResel.TReselEutranSfMedium) broadcast in system information, and the reselection hysteresis for the serving cell is equal to the sum of q-Hyst and q-HystSF.sf-Medium (specified by

CellResel.QHystSfMedium).

l High-speed UEs: The cell reselection time is equal to t-ReselectionEUTRA*t-ReselectionEUTRA-SF.sf-High (specified by CellResel.TReselEutranSfHigh) broadcast in system information, and the reselection hysteresis for the serving cell is equal to the sum of q-Hyst and q-HystSF.sf-High (specified by

CellResel.QHystSfHigh).

3.3 Tracking Area Registration

A UE informs the EPC of its Tracking Area (TA) by TA registration. The TA is a concept introduced to the LTE/SAE system for location management of UEs. A TA is identified by a Tracking Area Identity (TAI), which consists of the MCC, MNC, and Tracking Area Code (TAC).

TA registration can be performed in two ways: TA update and Attach/Detach.

3.3.1 Tracking Area Update

A UE performs TA updates in the following situations. That is, the UE sends a TA update request when any of the following conditions is met (For details, see section 5.3.3.0A "Provision of UE's TAI to MME in ECM-CONNECTED state" in 3GPP TS 23.401 R10, which was released in March 2011):

l The UE detects that it has entered a new TA when it finds that the TAI in the system information is different from any TAI stored in its USIM.

l The periodic TA update timer expires. This timer length is delivered to the UE through a non-access stratum (NAS) message.

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l The UE reselects to an E-UTRAN cell from another RAT system. l The RRC connection is released because of load balancing. l The information on UE capabilities stored in the EPC changes.

l The information on Discontinuous Reception (DRX) parameters changes. For details, see

3.6 Paging.

The UE informs the EPC of its TA by TA update. The EPC will send paging messages to all eNodeBs in the TA.

3.3.2 Attach/Detach

When a UE needs to obtain service from a network but is not registered to the network, the UE performs an Attach procedure for TA registration. For the detailed Attach procedure, see section 5.3.2.1 "E-UTRAN Initial Attach" in 3GPP TS 23.401 R10, which was released in March 2011.

After a successful Attach procedure, the UE is allocated an IP address. The Mobile

Equipment Identity (MEI) of the UE will be sent to the Mobility Management Entity (MME) for authentication.

When the UE fails to access the EPC or the EPC does not allow the access of the UE, a Detach procedure is initiated. After the Detach procedure, the EPC no longer pages the UE.

3.4 Cell Reservation and Access Control

Cell reservation and access control are two mechanisms for operators to control their networks.

l The cell reservation mechanism employs cell status indication and special reservations for controlling cell selection and reselection procedures. Cells can be reserved only for UEs in idle mode.

l The access control mechanism is implemented for UEs on the basis of access classes. To implement access control, one or more access classes are allocated to a UE and stored in the USIM. Note that among the access classes, access class 10 is signaled to the UE through system information.

3.4.1 Cell Reservation and Barring

UEs are notified of cell status by the following information in the SIB1:

l cellBarred (set by CELLACCESS.CellBarred): cell barring status. If a cell belongs to

multiple PLMNs, this information is common for all PLMNs.

l cellReservedForOperatorUse (set by CELLOP.CellReservedForOp): whether a cell is

reserved for an operator. This information is PLMN-specific.

If a cell is neither barred nor reserved for operator use, UEs can consider this cell as a candidate during cell selection and reselection procedures.

If a cell is not barred but is reserved for operator use, UEs treat this cell during cell selection and reselection procedures as follows:

l If UEs of access class 11 or 15 camp on their HPLMN or an EHPLMN, the UEs can treat this cell as a candidate.

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l Otherwise, UEs treat this cell as a barred cell.

If a cell is barred, UEs behave as follows during cell selection and reselection procedures: l The UEs cannot select or reselect this cell, not even for emergency calls.

l The UEs select another cell as follows:

– When intraFreqReselection (set by the CELLACCESS.IntraFreqResel parameter) in the SIB1 indicates that intra-frequency reselection is allowed, the UEs may select another cell on the same frequency if reselection criteria are fulfilled. When

CELLACCESS.IntraFreqResel in the SIB1 indicates that intra-frequency reselection is not allowed, the UEs do not reselect a cell on the same frequency as the barred cell. The value of intraFreqReselection in the SIB1 is specified by the CELLACCESS.IntraFreqResel parameter.

– The UEs exclude the barred cell as a candidate for cell selection or reselection for 300 seconds.

3.4.2 Access Control

For details, see Access Class Control Feature Parameter Description.

3.5 System Information Broadcast

This section describes the basic feature LBFD-002009 Broadcast of system information. Based on the contents of the System Information (SI) messages, SI is divided into one Master Information Block (MIB) and 13 System Information Blocks (SIBs). Huawei supports SIB1 through SIB12. SI messages are transmitted over the BCCH. Figure 3-3 shows the

relationships between the SI messages.

The MIB is transmitted over the BCH through an independent RRC message. The scheduling period of the MIB is 40 ms. The BCH is predefined by transport format. Therefore, the UE receives the MIB on the BCH without obtaining other information on the network.

The SIB1 is transmitted over the Downlink Shared Channel (DL-SCH) through an independent RRC message. The scheduling period of the SIB1 is 80 ms. Other SIBs are transmitted over the DL-SCH through SI messages, and the scheduling periods can be separately set. The SIBs with the same scheduling period can be transmitted through the same SI message, and one SIB can be contained in only one SI message. The SIB1 carries the scheduling period information of all the SIBs and mapping information from SIBs to SI messages. The SIB2 must be mapped to the SI message that corresponds to the first entry in the list of SI messages in the scheduling information. On the Physical Dedicated Control Channel (PDCCH), the UE obtains the time and frequency information of the SIB by parsing SI-Radio Network Temporary Identifier (SI-RNTI).

When the contents of the SI are changed, the eNodeB sends paging messages to instruct the UE in idle mode and UE in connected mode to read the new SI messages.