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Idle Mode and Common Channel Behavior WCDMA RAN USER DESCRIPTION


Copyright Š Ericsson AB 2008 – All Rights Reserved Disclaimer No part of this document may be reproduced in any form without the written permission of the copyright owner. The contents of this document are subject to revision without notice due to continued progress in methodology, design, and manufacturing. Ericsson shall have no liability for any error or damage of any kind resulting from the use of this document.

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Contents

Contents 1

Introduction

1

1.1

Scope

1

1.2

Target Groups

1

1.3

Revision Information

1

2

Overview

3

3

Functional Descriptions

5

3.1 3.1.1 3.1.2 3.1.3 3.1.4 3.1.5

PLMN Selection Service Types PLMN Selection at Switch-On Automatic PLMN Selection Mode Manual PLMN Selection Mode Roaming

5 6 7 7 8 9

3.2 3.2.1 3.2.2 3.2.3 3.2.4

Cell Selection and Reselection Cell Search Procedure Cell Selection Procedure Cell Reselection Procedure Hierarchical Cell Structures

9 11 12 14 17

3.3 3.3.1 3.3.2 3.3.3 3.3.4

Location and Routing Area Updating LA and RA Structure Normal LA and RA Updating Periodic LA and RA Updating IMSI Attach/Detach

19 19 20 20 20

3.4

Cell Update

21

3.5

URA Update

21

3.6 3.6.1 3.6.2 3.6.3

Paging Paging in Idle Mode and in state URA_PCH Paging in the CELL_FACH or CELL_DCH State Updated System Information Originating from the WCDMA RAN

22 22 24

3.7 3.7.1 3.7.2 3.7.3

System Information System Information Structure System Information Update Changing of Scheduling Information

25 25 26 30

3.8 3.8.1 3.8.2

Access Restriction Cell Specific Access Restrictions RNS Wide Access Restrictions

30 30 30

4

Engineering Guideline

33

4.1

Cell Selection

33

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Idle Mode and Common Channel Behavior

4.2 4.2.1 4.2.2

Cell Reselection Measurements Cell Ranking

34 34 37

4.3

HCS deployment example

39

4.4

Deployment of an Additional Carrier

42

4.5 4.5.1 4.5.2

GSM to WCDMA Cell Reselection Measurements Cell Ranking

43 43 44

4.6 4.6.1

Paging DRX Cycle Length Coefficient in Idle mode

45 45

4.7

Alternative SIB Scheduling to be applied when domain specific access restrictions are included in system information

45

4.8

Scheduling Block Deployment

46

4.9

SIB18 Deployment

47

4.10

Load-triggered Access Class Barring

47

5

Parameters

49

5.1 5.1.1 5.1.2 5.1.3 5.1.4 5.1.5 5.1.6

Descriptions Cell Selection and Reselection Location and Routing Area Updating URA Handling Paging System Information Load-triggered Access Class Barring

49 49 53 53 53 54 55

5.2

Values and Ranges

55

Reference List

63

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Introduction

1

Introduction A User Equipment (UE) that is powered on, but does not have a connection to the radio network, is defined as being in Idle mode. A UE in Idle mode can both access and be reached by the system. A UE that has an RRC connection is defined as being in Connected mode. A UE in Connected mode using the common channels RACH and FACH is defined as being in state CELL_FACH. A UE in Connected mode monitoring the paging channel is defined as being in state URA_PCH. The location of a UE in state URA_PCH state is known by the WCDMA RAN on a UTRAN Registration area (URA) level. A more detailed description of the different RRC states can be found in Reference [4].

1.1

Scope This document provides a high-level description of the Idle mode and the Connected mode behavior in state CELL_FACH and URA_PCH. The capabilities and the logic of these states are explained. The document also contains parameter information related to the functions performed in Idle mode, state CELL_FACH and URA_PCH. Section 4 on page 33 describes the engineering guidelines, which cover practical aspects of the parameter settings. Abbreviations and terms used in this document are explained in Glossary of Terms and Acronyms.

1.2

Target Groups This document is written for the following group of personnel: operators and, as an important starting point, those who want to understand the Idle mode and Common Channel behavior in greater detail in order to control the functions and optimize the parameter settings. It is assumed that users of this document have a working knowledge of 3G telecommunication and are familiar with WCDMA. Personnel working on Ericsson products or systems must have the training and competence required to perform their work correctly.

1.3

Revision Information Apart from editorial changes, this document has been revised according to Table 1 on page 2:

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Idle Mode and Common Channel Behavior

Table 1

Revision History

Revision

Reason for Revision

P6.0/P6.1

A

This is a new document based on 71/1553–HSD 101 02/5.

Both

The Functional Description and the Parameter section is updated with information about the features MBMS, Hierarchical Cell Structures (HCS) and the Scheduling Block (SB1). B

Functional Description and Parameters:

Both

• Clarified in section 3.2.4.1 that the following HCS configuration is invalid: hcsUsage.idelMode =FALSE; hcsUsage.connectedMode=TRUE • Engineering Guidelines: • HCS deployment example added in section 4.3. • Recommendations on SB1 deployment added in section 4.8 • Section 4.5.2 is updated with information about the GSM feature Combined Cell Reselection Triggering GSM to WCDMA. • Section 4.4 is updated to give general engineering guidelines for deployment of additional carriers. Functional Description, Engineering Guidelines and Parameter section updated with information about the features SIB18 for improved PLMN mobility and Load Triggered Access Class Barring.

2

P6.1

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Overview

2

Overview In Idle mode, the UE has no connection to the radio network, nor is a Radio Resource Control (RRC) connection established. Keeping UEs in Idle mode minimizes the use of resources both for the UEs and in the network. However, the UEs must still be able to access the system and be reached by the system with acceptable delays. For this, the following procedures need to be performed: •

PLMN selection

Cell selection and reselection

Location Area (LA) and Routing Area (RA) updating

Paging

System information broadcast

PLMN selection performs registration on a selected Public Land Mobile Network (PLMN). Cell selection looks for a suitable cell in the selected PLMN. Cell reselection ensures that the UE camps on the cell that gives the highest probability for successful monitoring of system and paging information and for successful establishment of a connection. LA and RA updating is necessary to inform the CN of the current LA or RA of the UE, so that the network can send a paging message to the UE. Paging makes the UE reachable by one or both of the Core Networks (CNs) supported by the PLMN. System Information Broadcast is required to provide the UE with parameters that control cell selection and reselection, paging, location and routing area updating, access, and other functions. The following procedures are performed by Connected mode UEs in state CELL_FACH and URA_PCH: • Cell selection and reselection • Paging • Reading of system information • Cell Update • URA Update (only in state URA_PCH) • PLMN selection

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Idle Mode and Common Channel Behavior

4

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Functional Descriptions

3

Functional Descriptions The tasks performed by Idle mode UEs and Connected mode UEs using the common channels can be divided in the following seven processes: •

PLMN selection

Cell selection and reselection

LA and RA registration

Paging procedure

Reading system information

Cell Update

URA Update

Figure 1 on page 5 illustrates the relationship between PLMN selection, cell selection and reselection, and LA and RA registration.

Automatic and Manual mode selection

Indication to user

PLMN Selection PLMN selected

PLMNs available

LR responses

Cell Selection and Reselection Registration area changes LA and RA Registration U 00 00073

Figure 1

3.1

Relationship between PLMN Selection, Cell Selection and Reselection, and LA and RA Registration

PLMN Selection The UE will select a PLMN at power-on or upon recovery from lack of coverage. It will first try to select and register on the last registered PLMN if one exists. If registration on a PLMN is successful, the UE shows this PLMN on the display,

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Idle Mode and Common Channel Behavior

and it is now allowed to perform or receive services from an operator. If there is no last registered PLMN, or if it is unavailable, the UE will try to select another PLMN either automatically or manually depending on its operating mode. The automatic mode utilizes a list of PLMNs in an order of priority, whereas the manual mode leaves the decision to the user and only shows the available PLMNs. The UE normally operates on its home PLMN. Another PLMN may be selected if, for example, the UE loses coverage. The UE will register on a PLMN in order to find a suitable cell to camp on. Registration has to be successful in order for the UE to be able to access the network. Section 3.1.1 on page 6 to Section 3.1.5 on page 9 describe how the UE attempts to select and register on a PLMN. For a more detailed description of the PLMN selection process, see Reference [2].

3.1.1

Service Types Camping on a cell is necessary for the UE to get access to some services in the network. The following three types of services are defined for the UE in Idle mode: •

Limited service, which allows the UE to make emergency calls only

Normal service, for public use on a suitable cell

Operator-related services, which allow the operator to test newly deployed cells without being disturbed by normal traffic.

The operator can establish cell access restrictions using the cellReserved parameter that allows the reservation of a cell for operator use only. It is also possible to restrict access for certain Access Classes using the parameter accessClassNbarred. Both parameters are sent in the system information. A UE obtains limited service when it camps on an acceptable cell. If the cell selection criteria are fulfilled, the cell is considered acceptable. A cell that allows normal service is defined as a suitable cell. A cell is suitable when the following criteria are fulfilled:

6

The cell belongs to the selected PLMN.

The cell selection criteria are fulfilled.

The cell is not a part of a forbidden registration area.

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Functional Descriptions

3.1.2

PLMN Selection at Switch-On Whenever a UE is switched on or enters an area with acceptable coverage after coverage loss, it attempts to camp on the last registered PLMN or equivalent PLMN, if available. To speed up the PLMN selection procedure, the UE uses information about the last registered PLMN, such as carrier frequencies or the list of neighboring cells stored in the USIM before the UE was switched off. On each stored carrier frequency, the UE searches first for the strongest signal cell and reads its system information to verify the PLMN to which the cell belongs. It also reads the system information for PLMN identity, which consists of mcc and mnc. Then the UE decides whether the chosen cell is acceptable or whether at least one acceptable cell belonging to that PLMN exists. Finally, the UE attempts registration if the PLMN is allowed. If the last registered PLMN is not available, a registration attempt fails. If there is no registered PLMN stored in the USIM, the UE selects and attempts registration 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 on page 8. In Automatic mode, if no last registered PLMN exists or is available, the UE will select a PLMN that is available and allowed, in the following order: 1. Home PLMN (HPLMN), if not previously selected, according to the Radio Access Technologies (RATs) supported by the UE. 2. Each PLMN in the user-controlled PLMNs list in the USIM, if present, in order of priority, 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 CPICH fulfills the high-quality criterion. The high-quality criterion is fulfilled when CPICH RSCP level is greater than or equal to –95 (dBm). For GSM cells the high-quality criterion is fulfilled when the signal level is above –85 (dBm). A PLMN with at least one acceptable cell is considered available. If that PLMN is allowed, the UE tries to register on it. If registration is successful, the UE displays the selected PLMN.

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Idle Mode and Common Channel Behavior

When the UE cannot register on any PLMN in the user and operator lists, it attempts to register on other PLMNs according to the high-quality criterion. If the UE cannot register on any PLMN, it selects an available PLMN and enters a limited service state. If it does not find an available PLMN, the UE enters the non-service state, and waits until a new PLMN is available and allowed.

UE Switch on UE selects the last registered PLMN

UE checks if the PLMN is available (that is tries to find an acceptable cell)

No

Yes

No

UE tries to register on the selected PLMN

UE selects an available PLMN Id according to the list stored in priority order

Yes Yes

UE tries to register on the selected PLMN?

No

Sucessful Registration U 00 00075

Figure 2

3.1.4

PLMN Selection-Automatic Mode

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 user makes a manual selection, according to the available access technology for the chosen PLMN, 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 available PLMN in the forbidden PLMN

8

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Functional Descriptions

list, the UE attempts to register and may receive a positive acknowledgement 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 selected before 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 PLMN reselection.

3.1.5

Roaming Roaming is a service through which a UE is able to obtain services from another PLMN in the same country (national roaming area) or another country (international roaming area). The behavior that the UE must follow is specified by agreements among the network operators. A UE in Automatic mode, having selected and registered on a Visited PLMN (VPLMN) in its home country, 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

Cell Selection and Reselection The Cell Selection and Reselection Process described in this section applies to WCDMA cells. A more detailed specification of the process can be found in Reference [3]. The cell selection and reselection process allows the UE to look for a suitable cell in the selected PLMN and to camp on it. When a suitable cell is found, the UE camps on it in a state defined as “camped normally�. In this state, the UE monitors paging and system information, performs periodical radio measurements, and evaluates cell reselection criteria. If the UE finds a better cell, that cell is selected by the cell reselection process. The change of cell may imply a change of the RAT. The WCDMA RAN is sensitive to intra frequency interference, which may depend on the data rate, traffic load, or modified radio link due to multipath fading. Therefore, the measurements that are used in the cell selection and reselection process are not only the signal strength but also the quality value. These measurements are performed on the Common Pilot Channel (CPICH). Two different strategies, initial cell selection and stored information cell selection, can be used in the cell selection process, as shown in Figure 3 on page 10.

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Idle Mode and Common Channel Behavior

Start

Stored Information Cell Selection

no suitable cell found

Initial Cell Selection

suitable cell found no suitable cell found

acceptable cell found

suitable cell found Cell Selection when leaving connected mode

Connected mode

Camped normally

measurements evaluation

location registration failed no suitable cell found

suitable cell selected

Cell Reselection Process

Camped on an acceptable cell (Limited service)

In Automatic mode, new PLMN selection U 00 00074

Figure 3

Cell Selection and Reselection Procedure

Initial cell selection is used if the UE has no knowledge of the WCDMA radio frequency channels. Stored information cell selection is used if the UE knows the carrier frequencies that have previously been used. The UE must synchronize with the WCDMA RAN to read system information on the BCCH to select a PLMN and to find a suitable cell. The cell search procedure in Section 3.2.1 on page 11 performs the synchronization between the UE and the WCDMA RAN. For a more detailed specification of the Cell Selection and Reselection Process, see Reference [3].

10

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Functional Descriptions

3.2.1

Cell Search Procedure The cell search procedure allows the UE to acquire slot and frame synchronization and to get the downlink primaryScramblingCode associated with the cell using the Synchronization Channel (SCH). The physical channels involved in the cell search procedure are the Primary Synchronization Channel (P-SCH), the Secondary Synchronization Channel (S-SCH), and the CPICH. The procedure is based on the following steps, which are also shown in Figure 4 on page 11.

Start

Detecting slot synchronization

Detecting frame synchronization and primary scrambling code group

Detecting primary scrambling code (cell) and beginning System Information reading

End U 00 00076

Figure 4

Cell Search Procedure

1. The UE acquires slot synchronization by correlating the information on the P-SCH with primary synchronization code, which is common to all cells, and by detecting peak values at the matched filter output. 2. The UE obtains frame synchronization and determines the scrambling code group of the cell (made up by eight primary scrambling codes) by correlating the information on the S-SCH with all secondary synchronization code sequences and by detecting the peak value, since the cyclic shifts of sequences are unique. 3. The UE determines the primaryScramblingCode by correlating the CPICH with all codes within the scrambling code group identified in Step 2 on page 11. When the primary scrambling code has been identified, the Primary Common Control Physical Channel (P-CCPCH) will be detected and the UE is able to read the information on the BCCH.

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Idle Mode and Common Channel Behavior

The need for execution of all or part of the cell search procedure depends on the information, such as primary scrambling code group, stored in the UE if the UE was previously registered on the PLMN.

3.2.2

Cell Selection Procedure If the UE does not find a suitable cell of the PLMN on which it was previously registered, and it has already used the stored information cell selection procedure, the initial cell selection procedure is started. This procedure does not require knowledge of radio frequency channels in the WCDMA band. The UE scans all WCDMA radio frequency channels to find a suitable cell. On each carrier, the UE searches for the cell with the highest signal level, according to the cell search procedure, and reads the system information on the BCCH. The information on this channel is mapped to one Master Information Block (MIB) and some System Information Blocks (SIBs). The UE reads the PLMN identity, formed by the mcc and the mnc sent in the MIB, and determines the cell to which PLMN belongs. The UE verifies that all requirements for a suitable cell are fulfilled. In particular, it checks whether the cell selection criteria are fulfilled. If the UE does not find a suitable cell, it attempts to camp on the strongest acceptable cell and obtain limited service. In this state, the UE tries regularly to find a suitable cell according to the RATs supported by the UE. In automatic PLMN selection, this consists of a new PLMN selection. On the BCCH, the UE receives information, such as the carrier frequency uarfcn in the downlink and in the uplink, belonging to the selected PLMN. The UE also reads the neighboring cell list to make measurements on adjacent cells, to verify whether a better cell exists than the serving cell. When the UE has information on carrier frequencies of the PLMN previously stored on the USIM, it may use the stored information cell selection procedure. The UE may have other information, such as the primary scrambling code group or the neighboring cells list stored on the USIM before UE switch-off or leaving a coverage area. This information simplifies the cell search procedure and speeds up the search for a suitable cell. After synchronization, the UE reads system information on the BCCH. If all requirements for a suitable cell are fulfilled, the UE selects that cell and tries to register. A suitable cell must fulfill the cell selection criteria. The UE bases its evaluation on two quantities: Squal and Srxlev. The Squal quantity has been introduced to evaluate the Signal to Interference Ratio (SIR) on the CPICH, expressed in terms of Signal to Noise Ratio in the CPICH (CPICH Ec/No). In order to evaluate whether cell selection criteria (S-criteria) are fulfilled, the UE calculates the following: Squal = Qqualmeas-qQualMin (only for WCDMA cells) Srxlev = Qrxlevmeas-qRxLevMin - Pcompensation (for all cells) Where:

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Functional Descriptions

Qqualmeas is the quality value for the received signal, expressed in CPICH Ec/No (dB) and measured by the UE. Cell parameter qQualMin indicates the minimum required quality value in the cell. It is sent in system information, in SIB3 for the serving cell, and in SIB11 for adjacent cells. Qrxlevmeas is the received signal strength measured by the UE and expressed in CPICH RSCP (dBm). Cell parameter qRxLevMin indicates the minimum required signal strength in the cell. It is sent in SIB3 for the serving cell and in SIB11 for adjacent cells. Pcompensation = max (maxTxPowerUl - P, 0); P is the maximum RF output power of the UE according to its class. Pcompensation is introduced for UEs that cannot transmit at maximum power on the RACH in the cell. The cell range decreases for those UEs. The cell parameter maxTxPowerUl indicates the maximum allowed transmission power when the UE accesses the system on RACH. It is broadcast in SIB3. The S-criteria are fulfilled when: Squal > 0 and Srxlev > 0 If all other requirements for a suitable cell are fulfilled, the UE attempts to register and, if necessary, performs LA or RA updating. If the UE finds a suitable cell, it camps on the cell in the state “camped normally”. In this state, the UE periodically evaluates whether a neighboring cell is better than the serving one by making Intra-frequency, Inter-frequency, and inter-system radio measurements. The UE attempts to make a cell selection in order to find a suitable cell on which to camp in the following cases: •

When a UE is switched on

When a UE in Idle mode has had a number of failed RRC connection requests

When a UE returns to Idle mode from the Connected mode on common channels (CELL_FACH state) after a number of failed cell update attempts

When a UE moves from dedicated mode to Idle mode The candidate cells for cell selection are the ones used immediately before leaving Connected mode. If no suitable cell is found, the UE can use stored information cell selection procedure to find a suitable cell.

When a UE returns to Idle mode after an emergency call on any PLMN

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Idle Mode and Common Channel Behavior

The UE selects an acceptable cell on which to camp. In this case, candidate cells for cell selection are the ones used immediately before leaving the Connected mode. If no acceptable cell on that PLMN is found, the UE continues to search for an acceptable cell on any PLMN. •

When a UE moves from dedicated mode to state CELL_FACH or URA_PCH.

3.2.3

Cell Reselection Procedure

3.2.3.1

General When camping on a cell, the UE shall continuously search for a better cell according to the cell reselection criteria. In order to perform cell ranking, the UE measures the serving cell and neighbor cells listed in SIB11 according to the measurement rules described in Section 3.2.3.2 on page 14. All measured cells fulfilling the S-criteria as defined in Section 3.2.2 on page 12 are ranked according to the R-criteria described in Section 3.2.3.3 on page 16. If the UE finds a more suitable cell it reselects onto that cell and camps on it. Note that separate measurement rules and cell reselection criteria apply for the UE if HCS is used in the cell. This is further described in Section 3.2.4 on page 17. The high mobility state as specified in Reference [3] is not supported.

3.2.3.2

Measurement rules for cell reselection The decision about when intra-frequency measurements are performed is made using the sIntraSearch parameter in relation to Squal: •

If the Squal value is greater than the value for sIntraSearch, the UE does not need to perform intra-frequency measurements.

If the Squal value is less than or equal to the sIntraSearch value, the UE performs intra-frequency measurements.

If the value for sIntraSearch is not sent to the serving cell, the UE performs intra-frequency measurements.

The decision about when inter-frequency measurements are performed is made using the sInterSearch parameter in relation to Squal:

14

If the Squal value is greater than the value for sInterSearch, the UE does not need to perform inter-frequency measurements.

If the Squal value is less than or equal to the sInterSearch value, the UE performs inter-frequency measurements.

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Functional Descriptions

If the value for sInterSearch is not sent for the serving cell, the UE performs inter-frequency measurements.

If a UE has selected a MBMS service that is currently ongoing measurements shall be performed on inter-frequency cells belonging to the MBMS Preferred layer even if the Squal value is greater than the value for sInterSearch The decision about when GSM measurements are performed is made using the sRatSearch parameter in relation to Squal and the sHcsRat parameter in relation to Srxlev: •

If the Squal value is greater than the value for sRatSearch and the Srxlev value is greater than the value for sHcsRat, the UE does not need to perform measurements on GSM cells.

If the Squal value is less than or equal to the sRatSearch value and/or the Srxlev value is less than or equal to the sHcsRat value, the UE performs measurements on GSM cells.

Note that only UEs supporting 3GPP Rel- 5 CR 130 on TS 25.304 are able to base the start of GSM measurements on both CPICH Ec/N0 and CPICH RSCP (using both sRatSearch and sHcsRat). Other UEs will only use the CPICH Ec/N0 condition (Squal <= sRatSearch) to decide when to start measurements of GSM neighbors. In state CELL_FACH, the parameters fachMeasOccaCycLenCoeff and interFreqFddMeasIndicator are used to control the UE measurement activities for inter-frequency and inter-RAT neighbors. If fachMeasOccaCycLenCoeff is set to a value > 0, the UE performs inter-frequency and inter-RAT measurements during FACH measurement occasions. FACH measurement occasions are defined as being the frames where the following equation is fulfilled: SFN = C-RNTI mod n * 2^k, n = 0, 1, 2, etc k is an integer defined by the parameter fachMeasOccaCycLenCoeff C-RNTI is the cell UE identity (16 bits) If the UE (according to its measurement capabilities) is able to perform inter-frequency and/or inter-RAT measurements simultaneously as receiving the SCCPCH of the serving cell, it may also perform measurements on other occasions than specified above. If fachMeasOccaCycLenCoeffis set to 0, the parameter is not sent in system information and the UE is not allowed to leave the SCCPCH in order to perform measurements on other frequencies and RATs. If the parameter interFreqFddMeasIndicator is set to TRUE, the UE will evaluate cell reselection criteria on inter-frequency cells in state CELL_FACH.

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Idle Mode and Common Channel Behavior

If the parameter interFreqFddMeasIndicator is set to FALSE, the UE will neither perform measurements nor evaluate cell reselection criteria on inter-frequency cells in state CELL_FACH. 3.2.3.3

Cell reselection criteria The UE shall perform ranking of all measured cells fulfilling the cell selection criteria (S-criteria) as defined in Section 3.2.2 on page 12. Only those cells the UE is mandated to measure according to the measurement rules shall be considered for cell ranking The cells are ranked according to the R-criteria: R(serving) = Qmeas(s) + qHyst(s) + Qoffmbms R(neighbor) = Qmeas(n) - qOffset(s,n) + Qoffmbms - TO(n) Qmeas is the quality value of the received signal, which is derived from the average CPICH Ec/N0 or CPICH RSCP level for WCDMA cells and from the average received signal level for GSM cells. (s) and (n) denotes the serving and the neighbor cell values respectively. qHyst(s) is the hysteresis value that is read in system information of the serving cell. The value is set by the configurable parameters qHyst1 used when the ranking is based on CPICH RSCP and qHyst2 used when the ranking is based on CPICH Ec/N0. qOffset(s,n) is the offset between the serving cell and the neighbor cell and can be used to move the border between two cells. The value is defined per cell relation and is set by the configurable parameters qOffset1sn used when the ranking is based on CPICH RSCP and qOffset2sn used when the ranking is based on CPICH Ec/N0. Qoffmbms is an offset applied to cells belonging to the MBMS Preferred layer. The value is defined by the parameter qualityOffset and is signalled to the UE on the MBMS control channel MCCH. The offset is used by the UE to prioritize cells on a frequency layer on which the MBMS service is transmitted and shall be applied to the R-criteria only when this service is ongoing. The process is called Frequency Layer Convergence and is further described in MBMS. TO(n) is a temporary offset applied to the R criteria only if HCS is used in the serving cell, see Section 3.2.4 on page 17 for more details. Ranking of GSM neighbors is always made using the measurement quantity CPICH RSCP. For WCDMA neighbors it is possible to control whether the ranking is made using CPICH RSCP or CPICH Ec/N0. This is configured using the cell parameter qualMeasQuantity. If both WCDMA and GSM cells fulfill the S criteria, a first ranking is made using the measurement quantity CPICH RSCP. If a GSM cell is ranked as the best candidate, the UE performs cell reselection to that cell. If a WCDMA cell is

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Functional Descriptions

ranked as the best candidate and the measurement quantity for cell reselection is set to CPICH RSCP, the UE performs cell reselection to that cell. If a WCDMA cell is ranked as the best candidate and the measurement quantity for cell reselection is set to CPICH Ec/N0, the UE performs a second ranking of the WCDMA cells based on CPICH Ec/N0. The UE reselects the new cell if it is better ranked than the serving cell during a time interval treSelection.

3.2.4

Hierarchical Cell Structures

3.2.4.1

General The feature Hierarchical Cell Structures (HCS) makes it possible to control camping of UEs in Idle mode and in states CELL_FACH and URA_PCH, not only according to best cell using the measurement quantity CPICH RSCP or CPICH Ec/N0, but also according to cell hierarchy. If the feature is activated separate measurement rules and cell reselection criteria as defined in Section 3.2.4.2 on page 18 and Section 3.2.4.3 on page 18 are applied by the UE. The use of HCS is controlled by the cell parameters hcsUsage.idleMode and hcsUsage.connectedMode. The values are signaled to the UE in system information SIB11 and SIB12. If the parameter hcsUsage.idleMode is set to TRUE, the idle mode UE will apply the HCS measurement rules and cell reselection criteria as defined in this section. If the parameter hcsUsage.connectedMode is set to TRUE the connected mode UE in state CELL_FACH and URA_PCH will apply the HCS measurement rules and cell reselection criteria as defined in this section. Note that the following setting is not a valid HCS configuration: hcsUsage.idleMode = FALSE hcsUsage.connectedMode = TRUE With this setting the HCS neighbor cell information can not be broadcast to the UE in SIB11 and the UE will not apply HCS rules in state CELL_FACH or URA_PCH. The HCS priority level is defined by an integer between 0 and 7. HCS priority level 0 is the lowest priority and level 7 is the highest priority. The HCS priority level for the serving cell is configurable and set by the parameter hcsSib3Config.hcsPrio. The HCS priority level for inter-frequency neighbor relations is configurable and set by the parameter hcsSib11Config.hcsPrio. For intra-frequency and GSM cell relations no HCS priority level can be configured and the default value according to Reference [4] applies, i.e. HCS priority level = 0.

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Idle Mode and Common Channel Behavior

If the UE has selected a MBMS service that is currently ongoing the UE adds an offset to the normal HCS priority for all cells (serving and neighbor cells) belonging to the MBMS Preferred layer. The offset is configurable and set by the cell parameter hcsPrioOffset. The value is signaled to the UE on the MBMS control channel MCCH. Hierarchal Cell Structures is a license controlled feature, and a software key is necessary for activation. For more information see Handling of License Control. 3.2.4.2

Measurement rules for cell reselection when HCS is used The measurement rules for cell reselection when HCS is used is specified in Reference [3], section 5.2.6.1.2. The following parameters controlling the measurement rules are configurable in the network and sent to the UE in system information SIB3: Table 2

Parameters controlling the measurement rules for cell reselection when HCS is used

Parameter name in 25.304

Corresponding operator configurable parameter name

SinterSearch

sInterSearch

SintraSearch

sIntraSearch

SsearchHCS

hcsSib3Config.sSearchHcs

Slimit,SearchRAT

sRatSearch

SHCS,RAT

sHCSRat

For more details regarding value range etc, see Section 5.2 on page 55. 3.2.4.3

Cell reselection criteria when HCS is used The quality level threshold criterion for HCS (H-criteria) is used to determine whether prioritized ranking shall apply. The H-criteria is defined by: H(s) = Qmeas(s) – Qhcs(s) H(n) = Qmeas(n) – Qhcs(n) – TO(n) Qhcs specifies the quality threshold level for applying the prioritized ranking. (s) and (n) denotes the serving and neighbor cell values respectively. The serving cell value is set by the configurable parameter hcsSib3Config.qHcs. Qhcs for Inter-frequency cell relations is set by the configurable parameter hcsSib11Config.qHcs. For intra-frequency and GSM cell relations the default value according to Reference [4] applies, i.e. Qhcs(n) = 0. TO(n) specifies the temporary offset applied to the H-criteria for a duration of PENALTY_TIME(n) after a timer T(n) has been started. See Reference [3], section 5.2.6.1.4 for more details regarding the start and stop of this timer.

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Functional Descriptions

The temporary offset is only applied for inter-frequency neighbor relations and the value is set by the configurable parameters hcsSib11Config.temporaryOffset1 used if the quality measure is RSCP and hcsSib11Config.temporaryOffset2 used if the quality measure is Ec/N0. The timer T(n) is configurable for inter-frequency cell relations and set by the parameter hcsSib11Config.penaltyTime. For intra-frequency and GSM cell relations no temporary offset is applied. The UE shall perform ranking of all cells with highest HCS_PRIO among the measured cells fulfilling the S- and H-criteria (S > 0 and H ≥ 0). If no cell fulfils the H-criteria, the UE shall not consider the HCS priority when ranking the cells. The cells shall be ranked according to the R-criteria specified in section Section 3.2.3.3 on page 16. When HCS is used a temporary offset, TO(n), is applied to the R-criteria. The temporary offset is controlled using the same set of parameters as specified for the H-criteria above. Furthermore, if the Qoffmbms is applied to the R-criteria the UE shall use the value “infinity” for this parameter (even if another value is signalled on the MBMS control channel MCCH).

3.3

Location and Routing Area Updating After a UE has found a suitable cell and can access services requiring registration, it tries to register on the chosen PLMN. If the Location Area Identity (LAI) or Routing Area Identity (RAI), read on system information, is different from the one stored on the USIM before UE switch-off, the UE performs a LA or RA registration update. When a UE in Idle mode moves into a new cell in a new LA or RA or into a new PLMN, it performs a registration area update. The LA or RA update procedure is managed by the CN and is transparent to the WCDMA RAN. The three types of registration update are normal, periodic, and IMSI attach or detach. For a more detailed specification of the Location and Routing Area updating, see Reference [2].

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 switched services. Each area, LA or RA, may consist of cells of one or more RNC, which are 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 an LAI, formed by a PLMN Identity and a Location Area Code (lAC)

The RA is identified by an RAI, formed by an LAI and a Routing Area Code (rAC)

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Idle Mode and Common Channel Behavior

These parameters are sent in the system information.

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, or when the UE is unknown to the CN. The UE reads the LAI and the RAI in the system information and detects that one 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/or RA update request is sent by the UE to the WCDMA RAN. 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 to avoid 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 a timer, called t3212, which gives the time interval between two consecutive periodic location updates. The value is sent by the WCDMA RAN to UEs on the BCCH. The periodic RA update is controlled by a timer, called t3312, which gives the time interval between two consecutive periodic routing updates. The value of the timer is sent by the CN to the UE in the IMSI attach or in the routing area update message accept (this is not a radio parameter).

3.3.4

IMSI Attach/Detach A location registration request indicating IMSI attach is made when the UE is activated in the same LA in which it was deactivated, and the system information indicates that IMSI attach/detach is used. The IMSI attach/detach procedure allows the UE to avoid unnecessary paging attempts from the CN. It is managed by the cell parameter att sent on the BCCH. This parameter informs the UE whether the IMSI attach/detach procedure is to be applied. If the parameter att is set to 1, the UE sends an “attach” or “detach” message to the CN when it is powered on or off indicating whether the UE is active or inactive in the network. The CN avoids performing paging attempts when IMSI detach is applied and the UE is switched 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 in the same LA or RA in which it was switched off. If the registration area is changed, a normal LA update is performed by the UE.

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Functional Descriptions

3.4

Cell Update In state CELL_FACH, the procedure Cell Update is used to keep WCDMA RAN informed about the UEs location on a cell level. Cell Update is initiated in the following cases: •

A UE in state CELL_FACH enters a new cell.

As part of a supervision mechanism, Cell Update is performed periodically by UEs in state CELL_FACH. The periodicity is controlled by the timer t305, see Connection Handling.

If a UE in state CELL_FACH re-enters the service area after having been out of coverage when a periodic Cell Update should have been sent.

The Cell Update procedure is also initiated by the UE in the following cases:

3.5

A UE in state URA_PCH has uplink data to transmit

A UE in state URA_PCH state is paged by the network. The page can be either UTRAN or CN initiated.

A UE in state CELL_FACH detects RLC unrecoverable error in an AM RLC entity.

URA Update In state URA_PCH, the procedure URA Update is used to keep WCDMA RAN informed about the UEs location on a URA level. URA Update is initiated in the following cases: •

A UE in state URA_PCH enters a new cell not belonging to the same URA that the UE is registered in.

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.

As part of a supervision mechanism, URA Update is performed periodically. The periodicity is controlled by the timer t305, see Connection Handling

In the response to the URA Update, WCDMA RAN selects which URA the UE shall be registered to. Also for periodical URA Updates, where the UE might not have moved, the selected URA has to be specified by the network. System Information Block Type 2 contains the URA identities of the URAs configured in the cell. Note that the same cell can belong to maximum 4 different URAs.

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Idle Mode and Common Channel Behavior

3.6

Paging The purpose of this function is to enable the CN to page a UE for a terminating service request or for the WCDMA RAN to inform all UEs that the system information has been modified. The function is also used by the WCDMA RAN to initiate a channel switch from state URA_PCH to state CELL_FACH. A UE may be paged when it is in Idle mode, in CELL_FACH state, URA_PCH and in CELL_DCH state. For UEs in CELL_FACH state and CELL_DCH state, the paging message is sent on the dedicated control channel. For UEs in Idle mode, the paging message is broadcast in an LA, a RA, or a global RNC area. Paging messages are sent in all cells in an LA or RA, so it is necessary to find a trade-off between the number of LA or RA registration attempts and the paging load. The paging load will increase with larger LA and RA while the registration load will decrease with larger LA and RA. For UEs in state URA_PCH, the paging message is sent in all cells belonging to the URA where the UE is currently registered.

3.6.1

Paging in Idle Mode and in state URA_PCH When the UE is in Idle mode or in state URA_PCH, two different physical channels are used in order to exchange proper information between the WCDMA RAN and the UE: the PICH and the S-CCPCH (carries the PCH). There is a fixed timing relation between a PICH frame and the associated S-CCPCH frame. Figure 5 on page 22 illustrates this timing relation.

TPICH PICH frame containing paging indicators Associated S-CCPCH frame

U 00 00068

Figure 5

Timing between Paging Indicator and Paging Message

The PICH is used to indicate to the UE when it should read the S-CCPCH. PCH is used to carry the RRC message â&#x20AC;&#x153;Paging type 1â&#x20AC;?, which contains the actual paging information. The number of times the WCDMA RAN will transmit the paging information to a UE is determined by the configurable parameter noOfPagingRecordTransm.

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Functional Descriptions

Discontinuous Reception The UE listens to the PICH only at certain predefined times, reducing power consumption. The periodicity of these searches is set by the system and the time interval is called Discontinuous Reception (DRX) cycle. Different DRX cycles are used for circuit switched and packet switched services in Idle mode. A separate DRX cycle is also used to page Connected mode UEs in state URA_PCH. Each PICH frame consists of a number of paging indicators. The UEs are divided in a number of groups and each group reads a specific paging indicator that tells whether the associated UE should read the S-CCPCH. If a page indicator is set to 1, there can be a paging message on the S-CCPCH for the corresponding UE. If a certain paging indicator indicates that there is a page, all UEs in that group go to read the Paging type 1 message that may contain one or more paging records. Each paging record contains IMSI (or TMSI or P-TMSI) to identify which UE is paged. See Reference [3] for more details. The paging occasion specifies times when a UE should monitor its paging indicator. The paging occasion is calculated using IMSI and DRX Cycle Length. Figure 6 on page 24 shows the paging occasions for four different UE where each has its own specific IMSI and different DRX cycle lengths. The time period between two consecutive paging occasions is calculated as follows: DRX cycle length = 2k*10 (ms) Where: k

Integer defined by the cnDrxCycleLengthCs parameter for circuit-switched services and by the cnDrxCycleLengthPs for packet-switched services. For paging of Connected mode UEs in state URA_PCH, k is an integer defined by the parameter utranDrxCycleLength.

10 ms

Period equal to the system frame number (SFN) duration, which is the time interval between two consecutive SFNs

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Idle Mode and Common Channel Behavior

SFN:

... 64

96

128

160 192 224 256 288

320 ...

DRX cycle length (=640ms)

a) k=6, IMSI1 DRX cycle length (=640ms)

b) k=6, IMSI2 DRX cycle length (=5120ms)

c) k=9, IMSI3 DRX cycle length (=5120ms)

d) k=9, IMSI4 U 00 00067

Figure 6

Paging Occasions

The RNC may be connected to two different CN domains that may use different DRX cycle lengths to page UEs in Idle mode. These are broadcast in the system information. A UE that is attached to both CN domains uses the shortest of those DRX cycle lengths. A UE may also choose an individual packet switched DRX cycle and issue a request to the CN to be paged with that DRX cycle length when it is in Idle mode. This procedure is transparent to the WCDMA RAN. The DRX cycle to be used in Connected mode (state URA_PCH) is sent to the UE using dedicated messages. The same value applies for both CN initiated and UTRAN initiated paging in state URA_PCH.

3.6.2

Paging in the CELL_FACH or CELL_DCH State When a connection exists between the WCDMA RAN and the UE, the SRNC determines that a RRC connection has already been established by this UE and the RRC message “Paging type 2” is used to carry paging information. Since it is sent on a dedicated control channel, this message is intended only for one particular UE.

3.6.3

Updated System Information Originating from the WCDMA RAN The RRC paging procedure sends consecutive “Paging type 1” messages for a period of time sufficient for the UE, using maximum possible DRX cycle length, to get this information at least once. The number of times a UE (that uses maximum possible DRX cycle length) hears the updated system information is defined by the parameter noOfMaxDrxCycles.

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Functional Descriptions

3.7

System Information The purpose of system information distribution is to broadcast system information to the UEs in the cells of the WCDMA RAN so the UEs can read and use this information for proper access to the system. The system information is regularly broadcast to the UE on the BCCH. It contains parameters related to functions such as Cell Selection and Reselection, Measurement Management, Location and Routing Registration, Handover, and Power Control. When a parameter in the system information is changed, all UE in a cell are notified by a paging message or by a system information change indication message. System information is read and used by UEs in Idle mode and UEs in CELL_FACH and URA_PCH state.

3.7.1

System Information Structure The system Information elements are broadcast in System Information Blocks (SIBs). An SIB groups system information elements related to the same kind of activity control. Different types of SIB exist, and each type contains a specific collection of information. The Master Information Block (MIB), which is also broadcast over the air interface, gives references and scheduling information to a number of SIBs in a cell, as shown in Figure 7 on page 25.

Master Information Block

System Information Block 1

System Information Block 2

...

System Information Block n U 00 00072

Figure 7

Organization of System Information Blocks

SIB scheduling information can also be contained in a separate Scheduling Block (SB1). The Scheduling Block is always referenced from the MIB. The configurable parameter schedulingBlockEnabled controls whether the Scheduling Block is used or not. If the parameter is set to TRUE the Scheduling Block is sent on the broadcast channel and SIB scheduling information is divided between the MIB and SB1. If the parameter is set to FALSE the Scheduling Block is not sent on the broadcast channel and all SIB scheduling information is contained in the MIB. If the Scheduling block is activated or deactivated (i.e. the value of parameter schedulingBlockEnabled is changed) an update of system information is initiated.

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Idle Mode and Common Channel Behavior

The MIB is transmitted according to standardized scheduling parameters. A UE is always able to find the MIB on the BCCH and to get the scheduling information for the other SIBs. The MIB is sent regularly on the BCCH. It also contains information elements for handling and scheduling SIBs and SBs, such as the appropriate repetition period and the value tag. The SIBs contain all information necessary for UEs to work properly in both Idle and Connected mode. Each SIB contains different kinds of information. Table 3 on page 26 contains a description of the information that is carried by the MIB and the SIBs. Table 3

Contents of System Information Messages

System Information Blocks

Contents

MIB

PLMN identity for serving cell, SIB Scheduling Information

SB1

SIB Scheduling Information

SIB1

Paging parameters, Timers and counters in Idle and Connected mode, LA and RA updating

SIB2

URA identity list

SIB3

Cell selection and reselection parameters

SIB5 and SIB5bis

Paging parameters, Cell and common channel configuration

SIB7

Power control on common channel

SIB11

Measurement management, Cell selection and reselection parameters

SIB12

Measurement management

SIB18

PLMN identity for GSM neighbors listed in SIB11.

The BCCH is mapped to the BCH. The RBS continuously transmits the SIBs in system information messages on the BCH, in accordance with scheduling parameters received from the RNC. In case there are no URAs associated to the cell, SIB2 is not broadcast. Broadcast of SIB18 is introduced with the optional feature â&#x20AC;&#x153;SIB18, Enhanced Inter PLMN Mobilityâ&#x20AC;?. This is a license controlled feature, and a software key is necessary for activation. For more information see Handling of License Control. The parameter sib5bisEnabled controls whether SIB5 or SIB5bis is broadcasted on BCH, see Multiband operation for more details.

3.7.2

System Information Update A system information update can be triggered by, for example, measurement reports that affect the value of a broadcast system parameter. In addition,

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Functional Descriptions

reconfiguration of system parameters, change of repetition rate for a SIB, and change of start position will trigger an update procedure. When the system information is modified, the RNC sends the modified SIBs to the RBS. Subsequently, the RBS broadcasts these SIBs on the BCH. In order to reduce power consumption, the UE does not always read the system information. System information update may fail and the RNC may attempt a new system information update request to the RBS for the cell. The RNC repeats the procedure until there is a positive response or until the maximum number of reattempts has been reached. The maximum number of update reattempts depends on the configuration of the parameter updateCellReattsNo. If the maximum number of reattempts is reached, the cell is blocked. SIBs are sent regularly on the BCH, and each SIB has its own repetition period, see Section 3.7.3 on page 30 for more details in Scheduling Information of these SIBs. The MIB has a fixed, predefined repetition rate equal to 80 ms, corresponding to an 8–SFN period. The MIB contains the PLMN identity to be used during the PLMN selection. Different rules are applied for rereading of different SIB types, depending on whether they contain static or dynamic information elements. For SIBs containing static parameters, the MIB contains a value tag as part of the scheduling information. When any of the information elements in system information is modified, the WCDMA RAN changes the value tag in the MIB that is related to the SIB containing the modified information element. If an information element changes in a SIB, the WCDMA RAN alerts all UEs in Idle mode and state URA_PCH in the cell to read system information by sending a “Paging type 1” message containing the information element “BCCH modification info”. The “BCCH modification info” information element contains the value tag for the MIB; by reading this information element, a UE knows whether it has to read the updated MIB. If the UE is in state CELL_FACH, it receives a System Information Change Indication message containing the information element “BCCH modification info” information element. The MIB value tag is not sent regularly on the FACH; its presence indicates changes in the system information on the BCH. The UE reads the updated MIB and compares the new value tag to the latest value tag for that SIB. If the value tag has changed, the UE reads the corresponding SIB again. Even if the value tag does not change, the UE considers the SIB invalid after a fixed, predefined period after reception and reads the SIB again. Some SIBs contain information elements that change so often that they need to be read at frequent periods. This type of SIB is not linked to a value tag in the MIB. This is the case of SIB7, which uses expiration time as a reread

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Idle Mode and Common Channel Behavior

mechanism. When the UE has acquired SIB7, a timer is started. When the timer expires, the information carried in the SIB is considered to be invalid. For SIB7, the expiration time is the value of the sib7RepPeriod parameter multiplied by the value of the sib7expirationTimeFactor parameter. The UE reads the system information on the BCCH when the following events occur: •

The UE is powered up.

The UE changes cell in Idle mode, state CELL_FACH or state URA_PCH.

The UE is informed of a change of System Information, when in Idle mode, state CELL_FACH or state URA_PCH.

The UE moves from dedicated mode to common mode.

The UE moves from dedicated mode to Idle mode.

The UE is in state CELL_FACH and the timer expires for SIBs with an expiration timer as reread mechanism (UEs in Idle mode and state URA_PCH may postpone reading the SIB until the content is needed).

The Area Scope column in Table 4 on page 28 specifies the area in which a SIB is valid. Table 4

SIB Characteristics

System Informa tion Block

Area Scope

UE Mode when Modification the Block is Read of System Information

MIB

cell

Idle mode

Value Tag

CELL_FACH URA_PCH SB1

cell

Idle mode

Value Tag

CELL_FACH URA_PCH SIB1

PLMN

Idle Mode

Value Tag

CELL_FACH URA_PCH SIB2

cell

URA_PCH

Value Tag

SIB3

cell

Idle Mode

Value Tag

CELL_FACH URA_PCH

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Functional Descriptions

System Informa tion Block

Area Scope

SIB5 and SIB5bis cell

UE Mode when Modification the Block is Read of System Information Idle mode

Value Tag

CELL_FACH URA_PCH SIB7

cell

Idle mode

Expiration time

CELL_FACH URA_PCH SIB11

cell

Idle mode

Value Tag

CELL_FACH URA_PCH SIB12

cell

CELL_FACH

Value Tag

URA_PCH SIB18

cell

Idle mode

Value Tag

CELL_FACH URA_PCH If the area scope is a cell, the UE reads the SIB every time a new cell is selected. If the area scope is PLMN, the UE checks the value tag for the SIB when a new cell is selected. If the value tag for the SIB in the new cell is different from the value tag for the SIB in the old cell, the UE reads the SIB again. If the value tags are the same, the UE can use the information read in the old cell. For SIB1, which has area scope PLMN, the value tag contains two parts, an update part and an area part. The update part is incremented internally by the RNC whenever the content of SIB1 is updated. The area part of the SIB1 value tag is configured using the sib1PLMNScopeValueTag cell parameter. SIB1 contains LA and RA information valid for the cell. For mobility reasons the UE needs to update this information whenever a LA or RA border is passed. To make this happen the setting of the parameter sib1PLMNScopeValueTag must be planned to make sure that neighboring LAs and RAs have different values. However, within one LA or RA the same setting can be used in all cells. PLMN scope really means LA or RA scope and the area part of the SIB1 value tag is associated with LA and RA, not associated with any other type of area.

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Idle Mode and Common Channel Behavior

3.7.3

Changing of Scheduling Information Two important parameters used in the creation of a Schedule for System Information are the Repetition Rate for a SIB sibxRepPeriod (where x = 1, 2, 3, 5, 7, 11, 12 or 18) and the Start Position for a SIB sibxStartPos (where x = 1, 2, 3, 5, 7, 11, 12 or 18). These parameters are configurable, see Section 5.2 on page 55 for details. Note that the repetition rate and the start position for SIB5 and SIB5bis are configured using the same parameters (sib5RepPeriod and sib5StartPos). The default values for the SIB scheduling parameters are carefully chosen to allow network expansion, that is, the default values cater for the situation where the amount of information to be broadcast increases, without creating a need to adjust these parameters (for example, new neighboring cell relationships can be added, without having to adjust the sib11RepPeriod and sib11StartPos). However, there are potential risks in adjusting these parameters. If adjustments cause a scheduling failure in the RNC, that is, the RNC is not able to create a working schedule based on newly configured sibxRepPeriod or sibxStartPos, then all cells controlled by that RNC will be locked and an alarm raise for each cell. For example, extreme care must be taken to ensure that a complete segment from one SIB does not try to occupy the same position as a segment from another SIB.

3.8

Access Restriction Access restrictions can be applied in a specific cell, cell group or all cells in the RNS in order to prevent users from making access attempts. Access class restrictions should not be used under normal operating conditions but can be applied when e.g. new cells are put into service or to avoid signalling or CN overload during extreme load conditions. Access class restrictions are broadcast in SIB3 for Access Classes 0 - 15. An overview of the different access classes can be found in Reference [5].

3.8.1

Cell Specific Access Restrictions Cell specific access class restrictions could be defined per UTRAN cell independent of CN domain for pre rel-6 UEâ&#x20AC;&#x2122;s using the operator parameter accessClassNBarred. CS and PS specific access class restrictions are supported for rel-6 and later UEâ&#x20AC;&#x2122;s and are controlled by the parameters accessClassesBarredCs and accessClassesBarredPs.

3.8.2

RNS Wide Access Restrictions

3.8.2.1

Load-triggered Access Class Barring Load-triggered Access Class Barring is a license controlled feature and a software key is necessary for activation. If activated, the feature provides load

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Functional Descriptions

dependent RNS-wide access class barring of Access Classes [0; 9] when the aggregated Iu-signalling connection setup rate exceeds the operator configured threshold iuSccpConRateThresh. The Iu-signalling connection setup rate is averaged over an operator configured measurement period iuSccpConRateMeasPeriod. When the load threshold is exceeded, 8 out of 10 access classes are barred in every operational cell in the RNS. Note that different access classes may be barred in different cells. The access class restrictions are removed in the following measurement periods, in step of 2 Access Classes at the time, if the Iu connection setup rate in that period has been reduced below the load threshold (adjusted with an internal hysteresis margin of 20%). Note that Load-triggered Access Class Barring does not remove cell specific access class restrictions configured by the operator parameters accessClassNBarred, accessClassesBarredCs and accessClassesBarredPs.

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Idle Mode and Common Channel Behavior

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Engineering Guideline

4

Engineering Guideline This section gives complementary information about practical engineering aspects of the radio functionality. It covers issues such as using the operator-definable radio parameters in different radio network scenarios, describing the reasoning behind the parameter settings, as well as adding examples of common settings when appropriate. The engineering guidelines have been preliminary updated for the latest changes in functionality. The choice of system for Idle mode camping is important. The multi-RAT UE camps on the system where it is expected to set up its services, and where it will be paged. In order for the multi-RAT UE to be able to access WCDMA-specific services, it needs to camp on WCDMA. The recommended strategy is, therefore, to camp on WCDMA whenever there is coverage. Outside WCDMA coverage, the UE camps on GSM to get access to standard GSM services. Once a WCDMA cell is selected, the parameter setting tries to keep the UE in this access technology as long as the quality and the received signal strength are good enough. Unless stated in this section, all discussions and parameters for Idle mode are also valid for Connected mode in state CELL_FACH and URA_PCH. Micro cells and pico cells have not been considered, but deployment of a second carrier is described. The parameter settings recommended in Section 4 on page 33 enable the camping strategy described above. Note that differences in behavior using the same parameter setting with different UE types have been observed. This indicates that when tuning Idle mode parameters, it is important to use the most common UEs in the system in order to achieve the desired behavior from the tuning.

4.1

Cell Selection Parameters qQualMin and qRxLevMin set the minimum levels for Idle mode camping. The recommended settings are the following: â&#x20AC;˘ qQualMin= -18 dB â&#x20AC;˘ qRxLevMin= -115 dBm It is recommended to keep these values constant. If there is a need to modify Idle mode cell size, the cell reselection parameters can be used for that purpose. The recommended setting for qRxLevMin is the lowest possible value that can be used without having a license key for the optional feature Increased

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Idle Mode and Common Channel Behavior

Downlink Coverage. In order for the UE to be able to read system information, the power levels on BCH must be set correctly, see Power Control. The setting of qRxLevMin is related to the power level on the Primary CPICH (primaryCpichPower), see Power Control. If the value of primaryCpichPower is increased, a UE at the cell border might have problems to access the system if the cell is loaded. To keep the cell size constant and compensate for the increase of primaryCpichPower, it is recommended to increase the setting of qRxLevMin accordingly. The parameter maxTxPowerUl is used to limit the maximum UE transmit power in a cell. It is also used to give UEs with lower power capability, and thus smaller UL coverage, a matching cell area in Idle mode. The value to configure depends on what UE type the network is planned for. Since most existing UEs have a power capability of 21 dBm or 24 dBm, it is recommended to set maxTxPowerUl to24 dBm. A comparison between cell sizes in Idle mode and Connected mode CELL_DCH state shows that the cell size is generally larger in Connected mode. One reason is that soft handover is used, which improves the radio link quality. The cell selection parameters work in the same way for a combined WCDMA-GSM network, for example, parameter qRxLevMin is set also for GSM neighbors. The initial process of PLMN selection decides which PLMN will be initially chosen. This process depends on UE type, as well as both operator-controllable and user-controllable data stored on the SIM card, such as preferred PLMN and RAT, see Reference [2]. That type of data cannot be managed by WCDMA RAN parameters. It is only when the UE has found a suitable cell, of the selected PLMN, that it is solely controlled by the cell reselection parameters, as set by the network in system information.

4.2

Cell Reselection This section explains the measurements and cell ranking done by UE.

4.2.1

Measurements The UE measures and evaluates the neighboring cells listed in system information (SIB 11).There are three different types of neighboring cells: • Intra-frequency neighbors • Inter-frequency neighbors • GSM neighbors

4.2.1.1

Measurements on Intra-Frequency Neighbors The decision on when to start measurements on intra-frequency neighbors for cell reselection is made using the parameter sIntraSearch. The

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Engineering Guideline

recommendation not to send this parameter in system information is achieved with the following setting: â&#x20AC;˘ sIntraSearch = 0 When this parameter is not sent, the UEs are configured to perform measurements on intra-frequency neighbors continuously. 4.2.1.2

Measurements on Inter-Frequency Neighbors If inter-frequency neighbors are defined in the cell, the parameter sInterSearch decides when the UE will start measure them. The recommendation not to send this parameter in system information is carried out with the following setting: â&#x20AC;˘ sInterSearch = 0 When this parameter is not sent, the UEs are configured to perform measurements on inter-frequency neighbors continuously. This setting will result in load balancing among the different frequencies as the UE will always perform cell reselection to the frequency on which the received quality is the best. If no inter-frequency neighbors are defined in the cell, the parameter sInterSearch can be set to any value, because it will not be used.

4.2.1.3

Measurements on GSM Neighbors If GSM neighbors are defined in the cell, the parameter sRatSearch and sHcsRat decide when the UE will start to measure them. The parameter sRatSearch is used to calculate a CPICH Ec/N0 threshold in relation to qQualMin whereas the parameter sHcsRat gives the corresponding CPICH RSCP threshold in relation to qRxLevMin. The recommended parameter values for sRatSearch and sHcsRat are 4 dB and 3dB, respectively. With this setting a UE in Idle mode or in CELL_FACH will start to measure GSM neighbors when either measured quality or signal strenght in the serving cell is less than or equal to the thresholds given below: Qqualmeas = qQualMin + sRatSearch = -18 + 4 = -14 dB OR Qrxlevmeas = qRxLevMin + sHcsRat + Pcompensation = -112 + Pcompensation dBm Note that the thresholds are set relatively low to avoid ping-pong behavior between WCDMA and GSM. Note also that with current default setting of sHcsRat (-105 dB) the CPICH RSCP threshold is not activated and the UE will only trigger start of GSM measurements based on the received quality in the serving cell. To activate the CPICH RSCP threshold the parameter sHcsRat should be set to a value >

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Idle Mode and Common Channel Behavior

0. All negative values of sHcsRat are interpreted as 0 by the UE according to Reference [4]. The use of the parameter sHcsRat in a non-HCS network was introduced late in 3GPP Rel-5 with CR 130 on TS 25.304. Therefore there will be old terminals that do not support this parameter. These terminals will behave in the same way as if the parameter is not activated, that is, they will only base the start of GSM measurements on the CPICH Ec/N0 threshold set by the sRatSearch parameter. From field testing it has been observed that the measured CPICH Ec/N0 and CPICH RSCP levels in the cell are not always correlated. For example when the UE moves out of WCDMA coverage, the CPICH Ec/N0 level measured in the UE might still be OK while the received signal level is decreasing. Therefore it is important to be able to start GSM measurements based on both measurement quantities. Figure 8 on page 36 illustrates when GSM measurements are performed by the UE based on the CPICH Ec/N0 threshold. A similar graph would also be applicable for the corresponding CPICH RSCP threshold.

CPICH Ec/No [dB]

-14 dB

sRatSearch=4 dB qQualMin = -18 dB

WCDMA measurements

WCDMA and GSM measurements

WCDMA measurements

t [s]

U 00 00388

Figure 8

Measurements on GSM Neighbors

If no GSM neighbors are defined, the parameters sRatSearch and sHcsRat can be set to any value, because they will not be used.

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Engineering Guideline

4.2.1.4

Inter-Frequency and GSM Measurements in state CELL_FACH When inter-frequency and/or GSM neighbors are defined in the cell, the following settings are recommended: • fachMeasOccaCycLenCoeff = 4 This setting should be used when either inter-frequency or GSM neighbors are defined in the cell. With this setting the UE will leave the FACH channel every 16th frame to perform measurements on other frequencies or RATs. • fachMeasOccaCycLenCoeff = 3 This setting should be used when both inter-frequency and GSM neighbors are defined in the cell. With this setting the UE will leave the FACH channel every 8th frame to perform measurements on other frequencies and RATs. If inter-frequency neighbors are defined in the cell the parameter interFreqFddMeasIndicator should be set to TRUE. With this setting the UE will evaluate the cell reselection criteria on inter-frequency cells in state CELL_FACH.

4.2.2

Cell Ranking Only measured neighbor cells that fulfill the cell selection criteria are ranked. The parameter qualMeasQuantity defines what ranking quantity is used. The recommended setting is qualMeasQuantity = 2 which corresponds to CPICH Ec/N0. With this setting the UE first makes a CPICH RSCP ranking. If a GSM cell is highest ranked, no more ranking is done. If a WCDMA neighbor is highest ranked, a second ranking takes place, this time according to CPICH Ec/No, and excluding all GSM neighbors. It is possible to control the cell size in Idle mode using the qHyst and qOffset parameters. The parameter qHyst (presented by qHyst1 and qHyst2) is added to the measured values of the serving cell. These parameters expand the cell borders of the serving cell in order to avoid ping-pong effects. The parameters qOffset1 or qOffset2 add an offset value for a cell-to-cell relation that are used to move the borders between the cells. A positive value of the parameter qOffset will make the neighbor decrease in size and a negative value will make the neighbor increase in size. The UE reselects the cell first on the ranked list when the reselection criteria have been fulfilled during a time interval of treSelection. The combination of settings for the parameters treSelection and qHyst below has in tests proven to give stable cell reselection behavior: • qHyst1 = 4 dB • qHyst2 = 4 dB • treSelection = 2 seconds

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Idle Mode and Common Channel Behavior

The setting for the parameter treSelection is a compromise between a too low value, triggering too many reselections in the fading radio environment, and a too high value, that slows down the process. The value for the parameter qOffset1sn is the offset between serving cell and target cell based on received signal strength. The parameter Qoffset2sn is the offset based on Ec/No. Note that the parameter qOffset1sn works identically for WCDMA-GSM and WCDMA-WCDMA neighbor relations. But the values of GSM RSSI and WCDMA CPICH RSCP are not of the same nature and, therefore, not directly comparable. Based on measurements of BLER on broadcast channels for the different radio access technologies, a rule of thumb that can be used for initial parameter settings is the following: [CPICH RSCP] + 7 dB is comparable to [GSM RSSI] For example, a measured RSCP on a WCDMA CPICH of –100 dBm would be comparable to a GSM broadcast channel RSSI of –93 dBm. A parameter setting of a GSM neighbor to qOffset1sn = +7 will thus make the received signal strength in the WCDMA and the GSM cell comparable. If the value is > 7 dB, the WCDMA cell is prioritized, that is, made larger, see Figure 9 on page 39. The recommended default values for the offset parameters are the following:

38

qOffset1sn = 0 dB for WCDMA neighbors

qOffset1sn = 7dB for GSM neighbors

qOffset2sn = 0 dB

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Engineering Guideline

GSM cell [RSSI]

SS [dBm] GSM cell [RSSI] - qOffset1

qOffset1=+7 dB

WCDMA cell [CPICH RSCP] + qHyst1 qHyst1=+4 dB WCDMA cell [CPICH RSCP]

qRxLevMin = -115 dB

Inter RAT cell reselection if qOffset1=0 and qHyst1=4

Figure 9

Inter RAT cell reselection if qOffset1=7 and qHyst1=4

t [s]

U 00 00387

Inter-RAT Cell Reselection from a WCDMA Serving Cell to a GSM Neighbor The default setting described above attempts to make the WCDMA and the GSM cells comparable in the ranking procedure. With this setting it is important that the UE will not start measuring on GSM cells too early, that is, the GSM cells should not be part of the ranking procedure until the quality of the serving WCDMA cell is bad enough. This is achieved with sRatSearch set to 4 dB (see Section 4.2.1.3 on page 35).

4.3

HCS deployment example As an example of how to configure HCS parameters, a two carrier network is assumed where HS is deployed on one of them, see Figure 10 on page 40. The non-HS carrier is the mainland carrier assumed having the most complete coverage of the two. The feature Hierarchical Cell Structure is used to move UEs in Idle mode to the non-HS carrier. Hence the expected starting point for the majority of connection establishments from Idle Mode will be the non-HS carrier. At connection establishment the HS users will follow the HS Cell Selection procedure and select a cell on the HS carrier, while non-HS users will establish their connections on the non-HS carrier. In case of high load in

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Idle Mode and Common Channel Behavior

the non-HS carrier, Inter Frequency Load Sharing will re-direct also non-HS users to the HS carrier.

FACH/URA

Cell f1A (Non-HS)

Cell f2A (HS)

Idle

f1

FACH/URA

Cell f2A (HS)

Idle

f2

Cell f1B (Non-HS) U0000713

Figure 10

The scenario used to demonstrate HCS: Two carriers with HSDPA deployed on one

When in state CELL_FACH or URA_PCH, typically reached due to low activity on the packet switched connection, it is desireable to remain on the HS carrier to avoid unnecessary transitions between carriers and keep the HS access time to a minimum. By setting qOffset2sn to a high value for all inter frequency neighbor relations of the HS cells, the reselection procedure to the non-HS carrier is practically disabled. To activate HCS for idle mode, parameter hcsUsage.idleMode is set to TRUE both in the HS and non-HS carrier cells. The non-HS carrier cells are assigned priority over the HS carrier cells by configuring hcsSib3Config.hcsPrio to 0 for all HS carrier cells and hcsSib11Config.hcsPrio to 1 for all cell relations to cells in the non-HS carrier. In the reverse direction the parameters are configured the opposite, i.e. hcsSib3Config.hcsPrio equals 1 for non-HS carrier cells and hcsSib11Config.hcsPrio equals 0 for cell relations to HS carrier. Parameter hcsSib3Config.sSearchHcs can be used to limit the area of the cell where HCS should be applied. For the part of the cell where the quality is better than (qRxLevMin + hcsSib3Config.sSearchHcs), HCS is applied and normal cell reselection criterias apply elsewhere. This is useful in the scenario where a large and smaller cell is co-located and it is preferred to primarily fill up to the smaller cell with traffic. The area, in which HCS shall be applied, is then configured to co-incide with the coverage area of the smaller cell. In the scenario described here it is assumed the co-located cells in the two carrier have similar coverage and by setting hcsSib3Config.sSearchHcs to 0 (or any negative value) HCS will be applied throughout the cell. If GSM neighbors are defined and used in the target carrier cells the setting of hcsSib3Config.sSearchHcs needs to be alligned with sHcsRat. To avoid a situation where UEs are redirected to a prioritized cell and immediately after start measuring GSM cells, hcsSib3Config.sSearchHcs should be configured with at least the same value as target cell sHcsRat. A few dBs

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Engineering Guideline

margin could be necessary to really ensure the redirection will not become an IRAT cell reselection via the non-HS carrier. As mentioned in Section 3.2.4.3 on page 18, must cells that are to be part of the HCS cell ranking qualify a certain quality threshold Qhcs (hcsSib3Config.qHcs for serving cells and hcsSib11Config.qHcs for neighbors). Setting a minimum acceptable quality level on qHcs makes it possible to avoid that cells with insufficient quality are reselected just because they have higher priority, hence it is recommended to set hcsSib11Config.qHcs equal or higher than target cell qQualMin. In the presence of GSM neighbors in the HCS target cell, it must be ensured that HCS is not redirecting UEs to cells with a signal level low enough to trigger GSM measurements. This is avoided by setting hcsSib11Config.qHcs equal to or a few dB higher than sRatSearch. For the serving cell on the non-HS carrier it is recommended to use a value of hcsSib3Config.qHcs that is a few dB higher than qQualMin. If GSM neighbors are defined in the cell, the value of hcsSib3Config.qHcs can be set a few dB higher than sRatSearch. There is also a temporary offset that can be used to avoid inter frequency transitions to occur too easily with ping pong reselection as a possible result. This means the inter frequency target cell need to prove an extra quality offset in order to qualify for the ranking during a certain penalty time. Both the additional quality offset and the penalty time are configurable. At the expiry of the penalty time the offset does not apply and the qualification level is qHcs. Table 5 summarizes the setting of the HCS parameters and qOffset2sn that creates good conditions for high performance packet switch data services by separating the HS services from R99 in a two carrier scenario. Further optimization is recommended to adapt to specific characteristics in different networks. Table 5

Setting of HCS parameters for improving HSDPA performance in a two carrier scenario.

Parameter

non-HS carrier

HS carrier

hcsUsage.idleMode

TRUE

TRUE

hcsUsage.connectedMode

FALSE

FALSE

hcsSib3Config.hcsPrio

1

0

hcsSib3Config.qHcs

> qQualMin if no GSM, or > sRatSea rch if GSM neighbors defined from non-HS carrier

default, i.e all neighbor cells included in HCS ranking

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4.4

hcsSib3Config.sSearchHcs

default, or ≥ sHcsRat if GSM neighbors defined from non-HS carrier

default, corresponds to 0 offset from qRxLevMin

hcsSib11Config.hcsPrio

0 (for cell relations to HS carrier)

1 (for cell relations to non-HS carrier)

hcsSib11Config.penaltyTime

not used

not used

hcsSib11Config.qHcs

default, i.e all neighbor cells included in HCS ranking

≥ qQualMin if no GSM, or ≥ sRatSearch for target cell, if GSM neighbors defined from non-HS carrier

hcsSib11Config.temporaryOffset1

0 [infinity]

0 [infinity]

hcsSib11Config.temporaryOffset2

0 [infinity]

0 [infinity]

qOffset2sn

50 dB (for all cell relations to HS carrier cells)

50 dB (for all cell relations to non-HS carrier cells)

Deployment of an Additional Carrier When an additional carrier is deployed cluster-wise or as a co-located hot spot cell there are two different camping strategies that can be implemented. The camping can be either equally distributed or biased towards a certain carrier. The policy of equal camping, not favoring any cell on any carrier, is implemented by setting qOffset2sn = 0 between cells on different carriers. Biased camping towards any cell on any carrier in any direction is implemented by tuning qOffset2sn. The parameter could be changed to -3 dB in the direction from the additional carrier cells down to the other carrier cells. In the opposite direction, qOffset2sn could be changed to +3 dB. A variant of biased camping is off-loading a carrier, that is, using the maximum (+50 dB) and minimum (-50 dB) values for qOffset2sn on the cell relations in order to steer all UEs to camp on a certain carrier. All the changes of qOffset2sn should be performed while monitoring the performance in the additional carrier cells to see that the intended traffic load on each carrier is achieved. For hot spot- and border cells on the additional carrier a higher qRxLevMin (or qQualMin) value can be applied in order to prevent UEs from setting up

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Engineering Guideline

connections close to the cell borders, and thereby directly start compressed mode measurements once a successful access is made. A threshold level slightly higher than the compressed mode start level (see Handover) is recommended initially, but lower values are also possible. The wanted behavior is that the additional carrier hot-spot cell is only loaded through the underlying co-located cell, and not the adjacent underlying cells. That is managed by either tuning qOffset2sn values on neighbor relations or by not defining underlying adjacent cells as neighbors in the direction from underlying cells to the additional hot-spot cell. According to 3GPP the UE is only required to measure on two non-used frequencies in addition to the currently used one. In a network with four carriers, it is therefore recommended to only configure inter-frequency cell relations to maximum two (of the three) non-used frequencies. Idle mode access across all the three different non-used frequencies can still be achieved by making sure that at least one of the two configured non-used frequencies has inter-frequency neighbors defined to the third non-used frequency. Note that the encoded message length of System Information Block type 11 (SIB11), carrying all neighbor cell information, will increase when the parameters qOffset2sn and qRxLevMin (or qQualMin) are changed as described above. In order to secure that the cell is not deactivated due to SIB scheduling errors it is recommended to limit the total number of neighbor relations defined in the cell (i.e. sum of Utran and Gsm relations) to 75 if qOffset2sn is changed (i.e. the parameter is set to a value <> 0 for inter-frequency cell relations). In hot spot and border cells the total number of neighbor relations defined in the cell shall not exceed 65 if other setting than default is used for parameters qOffset2sn and qRxLevMin (or qQualMin).

4.5

GSM to WCDMA Cell Reselection It is important to correlate the parameters in WCDMA and GSM to achieve the required Inter-RAT cell reselection behavior and thus a smooth coexistence. The following sections give a brief overview of GSM to WCDMA reselection. For extensive information on GSM parameters (written in capital letters in this document), ranges, and default values, see Reference [1].

4.5.1

Measurements When the multi-RAT UE enters an area without WCDMA coverage, it will camp on a GSM cell. In the GSM network, the parameter QSI controls when the UE performs measurements on WCDMA neighboring cells. This parameter is set per cell. The parameter QSI can be set in the four following alternative ways, so that WCDMA neighbors are measured: • Always • Never • When signal strength of the GSM cell is above a certain value • When signal strength of GSM cell is below a certain value

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Idle Mode and Common Channel Behavior

To enable cell reselection to WCDMA in areas with good GSM coverage, it is necessary to measure on WCDMA also when GSM coverage is good. The recommendation is that GSM cells that have WCDMA neighbors should have the QSI value set to Always.

4.5.2

Cell Ranking The algorithm for cell reselection from GSM back to WCDMA is controlled with the parameters FDDQMIN and FDDQOFF. The parameter FDDQMIN defines the minimum quality of a WCDMA cell for cell reselection, measured in CPICH Ec/No. This parameter is used to assure a sufficient quality of the candidate WCDMA cell. The parameter FDDQOFF sets an offset, positive or negative, between signal quality of GSM cells and the defined WCDMA neighbors. The two cell reselection criteria are the following: CPICH Ec/No > FDDQMIN and CPICH RSCP > RLA + FDDQOFF RLA is the received signal level average [dBm] for the serving GSM cell and its strongest GSM neighbors. For a multi-RAT UE just having entered GSM a ping-pong back to WCDMA is prohibited by a timer. The UE must fulfill the two cell reselection criteria above for 5 seconds in order to reselect the WCDMA cell. Furthermore, during a period of 15 seconds after the cell reselection to GSM, an additional offset of 5 dB will be added to the parameter FDDQOFF. With the GSM feature Combined Cell Reselection Triggering GSM to WCDMA, the mobile will reselect a suitable WCDMA cell if the following cell reselection critera are fulfilled: CPICH Ec/No > FDDQMIN - FDDQMINOFF and CPICH RSCP > FDDRSCPMIN - min((P - 21 dBm), 3 dB) and CPICH RSCP > RLA + FDDQOFF The parameter FDDQMINOFF can be used to make the requirement of signal quality less attractive for mobiles that support the signal strength criterion. P is the maximum RF output power of the UE in WCDMA. To achieve the preferred camping behavior, the multi-RAT UE should camp on WCDMA when there is coverage. This means that a negative value must be set for the parameter FDDQOFF if cell reselection is to be possible when GSM

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coverage is good. A drawback would be that cell reselection to a weak WCDMA cell could be made when GSM coverage is moderate. Such an effect could be prevented using a higher setting of the the parameter FDDQMIN. A setting of FDDQMIN>qQualMin + sRatSearch can prevent the UE for making cell reselection to a weak quality WCDMA cell, and furthermore prevent too early cell reselection measurements on GSM. Examples of other vital GSM parameters are parameter COEXUMTS, which determines if cell reselection to WCDMA is allowed at all, and the parameter ACCMIN, which is the UE minimum received signal level for permission to access the system on a control channel.

4.6

Paging

4.6.1

DRX Cycle Length Coefficient in Idle mode The setting of the DRX cycle length coefficient for paging in Idle mode is a trade off between call setup time and UE battery usage. A longer DRX cycle can significantly increase the UE standby time but it will also impact the call setup time for terminating calls. If the DRX cycle length is increased the average call setup time is delayed with (DRX_cycle_new - DRX_cycle_old)/2 ms. For example, if the DRX cycle length is changed from 640 ms to 1280 ms the terminating call setup time is increased with 320 ms on average. The DRX cycle length coefficient used in Idle mode is configured by the parameters cnDrxCycleLengthCs and cnDrxCycleLengthPs.

4.7

Alternative SIB Scheduling to be applied when domain specific access restrictions are included in system information When domain specific access restrictions are included in system information, either by setting the parameters accessClassesBarredCs and/or accessClassesBarredPs to TRUE for any of the Access Classes 0-15 or by activating the feature Load-triggered Access Class Barring, the encoded message length of SIB3 will increase. If the size of SIB3 is too large it might not be possible to schedule all SIBs on the broadcast channel using the default setting of the SIB parameters sibStartPos and sibRepPeriod specified in Section 5.2 on page 55. In order to secure that the cell is not deactivated due to SIB scheduling errors it is recommended to use an alternative setting of the SIB parameters when domain specific access restrictions are signalled to the UE in SIB3. The alternative setting is specified below: sib1RepPeriod = 32 sib2RepPeriod = 128

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Idle Mode and Common Channel Behavior

sib3RepPeriod = 32 sib5RepPeriod = 32 sib7RepPeriod = 16 sib11RepPeriod = 128 sib12RepPeriod = 32 sib18RepPeriod = 128 sb1RepPeriod = 128 sib1StartPos = 4 sib2StartPos = 118 sib3StartPos = 14 sib5StartPos = 6 sib7StartPos = 2 sib11StartPos = 20 sib12StartPos = 18 sib18StartPos = 122 sb1StartPos = 126

4.8

Scheduling Block Deployment When additional System Information Blocks are introduced on the broadcast channel the amount of SIB scheduling information will increase. In order to off-load the Master Information block (MIB) it’s possible to enable the usage of a separate Scheduling Block (SB1) by setting the parameter schedulingBlockEnabled to TRUE, see Section 3.7.1 on page 25 for more details. If the Scheduling Block is enabled it will contain scheduling information for SIB2 (if there are URA’s associated to the cell), SIB12 and SIB18 (if the feature SIB18 is installed and activated). All other SIB’s are still referenced from the MIB. The recommendation is to enable the Scheduling Block SB1 if at least one of the optional system information blocks SIB2 and/or SIB18 are scheduled on the broadcast channel.

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4.9

SIB18 Deployment Broadcast of SIB18 is a license controlled feature and a software key is necessary for activation. When activated, SIB18 will contain the PLMN id for each GSM relation listed in SIB11. Based on this information the UE can avoid to measure and evaluate GSM neighbors belonging to not allowed PLMN’s and thereby speed up the cell reselection procedure. The recommendation is to deploy SIB18 in areas with many GSM neighbors of not applicable networks.

4.10

Load-triggered Access Class Barring The Iu-signalling connection setup rate recorded by the PDF counter pmIuSccpConRate can be used as a guide to set the value of the parameter iuSccpConRateThresh controlling the threshold for applying Load-triggered Access Class Barring, see Section 3.8.2 RNS Wide Access Restrictions on page 30 for more details. The counter will use the same averaging period as defined for iuSccpConRateThresh and can be observed also when the feature Load-triggered Access Class Barring is deactivated. It is strongly recommended that the Iu-signalling network and core network are dimensioned to handle Iu-signalling load significantly above the normal busy hour load even if the Load-triggered Access Class Barring is applied. Load triggered access class barring shall only be used to protect the Iu-signalling network or core network in case of exceptionally high signalling load that could threaten the stability of the network. Also, if the Load-triggered Access Class Barring is used, the iuSccpConRateThresh shall be updated according to changes (e.g. capacity increase) in the Iu-signalling network and/or the core network. Every time the Load-triggered Access Class Barring is applied, FM-event RncFunction_loadTriggeredAccessClassBarring is thrown. The FM-event is visible in the RNC FM-event log. If the operator wishes to remove the access class restrictions applied by the Load-triggered Access Class Barring it can be done by deactivating the feature in the RncFeature = “Load-triggered access class barring” MO. When Load-triggered Access Class Barring is activated it is recommended to use the alternative setting of the SIB scheduling parameters as specified in Section 4.8 Scheduling Block Deployment on page 46.

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Parameters

5

Parameters This section describes all setable parameters that the operator can configure to control the UE behavior in Idle mode and in state CELL_FACH and URA_PCH.

5.1

Descriptions

5.1.1

Cell Selection and Reselection accessClassNbarr ed

Indicates whether or not access restrictions apply for Access Classes 0 to 15. If access restriction is indicated for a certain Access Class, the UEs assigned to this Access Class are allowed to camp in the cell but are not permitted to enter Connected mode by sending an RRC Connection Request message.

accessClassesBar redCs[n]

Indicates if CS domain specific access restrictions apply for Access Classes 0 to 15. If access restriction is indicated for a certain Access Class, the UEs assigned to this Access Class are allowed to camp in the cell but are not permitted to enter Connected mode by sending an RRC Connection Request message with purpose to setup a CS Signalling Connection. A connected mode UE shall also check this parameter before sending an INITIAL DIRECT TRANSFER towards the CS domain.

accessClassesBar redPs[n]

Indicates if PS domain specific access restrictions apply for Access Classes 0 to 15. If access restriction is indicated for a certain Access Class, the UEs assigned to this Access Class are allowed to camp in the cell but are not permitted to enter Connected mode by sending an RRC Connection Request message with purpose to setup a PS Signalling Connection. A connected mode UE shall also check this parameter before sending an INITIAL DIRECT TRANSFER towards the PS domain.

bandIndicator

Indicates for which GSM band, DCS 1800 or PCS 1900, the ARFCN for the GSM cell is valid. The parameter is defined per GSM neighbor.

bcchFrequency

BCCH frequency code in the GSM cell. The parameter is defined per GSM neighbor.

cellReserved

Indicates whether this cell will be reserved for operator use. If it is reserved, only UEs assigned to Access Classes 11 or 15 can treat the cell as candidate for

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Idle Mode and Common Channel Behavior

cell selection and cell reselection if the cell belongs to the home PLMN. For other UEs the cell is barred. The parameter is defined per cell.

50

fachMeasOccaCyc LenCoeff

Used by the UE to calculate the FACH measurement occasions (see Page 15). The parameter is defined per cell.

hcsPrioOffset

Priority offset added, if HCS is used, by UE to the normal HCS priority level of cells on the MBMS preferred frequency in order to keep/move the UE to that frequency. The parameter is set per cell and signalled to the UE on the MBMS control channel MCCH.

hcsSib3Config.hcs Prio

HCS priority level for the serving cell. The value is sent in system information SIB3.

hcsSib3Config.qHc s

Quality threshold level for applying prioritized hierarchical cell reselection. The parameter is defined per serving cell and the value is sent in system information SIB3. Separate mapping tables are used for measurement quantity Ec/N0 and RSCP.

hcsSib3Config.sSe archHcs

This threshold is used for measurement rules for cell reselection. When HCS is used, it specifies the limit for Srxlev in the serving cell below which the UE shall initiate measurements of all neighboring cells of the serving cell. When HCS is not used, it specifies the limit Srxlev in the serving cell below which the UE ranks inter-frequency neighboring cells of the serving cell. The parameter is sent in system information SIB3.

hcsSib11Config.hc sPrio

HCS priority level for the neighbor cell. The parameter is configurable per inter-frequency cell relation and the value is sent in system information SIB11.

hcsSib11Config.pe naltyTime

Specifies the time duration for which the Temporary offset(n) is applied for a neighbor cell. The parameter is configurable per inter-frequency cell relation and the value is sent in system information SIB11.

hcsSib11Config.qH cs

Specifies the quality threshold level for applying prioritized hierarchical cell reselection. The parameter is defined per inter-frequency cell relation and the value is sent in system information SIB11. Separate mapping tables are used for measurement quantity Ec/N0 and RSCP.

hcsSib11Config.te mporaryOffset1

Specifies the temporary offset applied to the H and R criteria when HCS is used. The parameter is used for GSM cells and for WCDMA cells when the quality measure for cell reselection is set to RSCP. The

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Parameters

parameter is configurable per inter-frequency cell relation and the value is sent in system information SIB11. hcsSib11Config.te mporaryOffset2

Specifies the temporary offset applied to the H and R criteria when HCS is used. The parameter is used for WCDMA cells when the quality measure for cell reselection is set to Ec/N0. The parameter is configurable per inter-frequency cell relation and the value is sent in system information SIB11.

hcsUsage.connect edMode

Controls whether HCS shall be used in states CELL_FACH and URA_PCH. The parameter is configurable per cell and the value is sent in system information SIB12. Note: In order for the UE to apply HCS rules in connected mode the corresponding parameter for idle mode (hcsUsage.idleMode ) must also be set to TRUE.

hcsUsage.idleMod e

Controls whether HCS shall be used in Idle mode. The parameter is configurable per cell and the value is sent in system information SIB11.

interFreqFddMeas Indicator

Indicates if the UE is required to perform measurements and evaluate the cell reselection criteria for Interfrequency neighbors in state CELL_FACH. The parameter is defined per cell.

maxTxPowerUl

UE maximum transmission power on the RACH when accessing the system. The parameter is also used to calculate the cell selection criteria Srxlev. It is defined per serving cell and per WCDMA neighbor and GSM neighbor.

mcc

Mobile Country Code part of the PLMN identity used in the radio network.

mnc

Mobile Network Code of the PLMN identity used in the radio network.

nmo

Network operation mode that indicates whether the Gs interface between the SGSN and MSC/VLR is installed. The parameter is defined per Routing Area.

primaryScrambling Code

Primary downlink scrambling code to be used in the cell.

qHyst1

Hysteresis value of the serving cell to be used for cell ranking based on CPICH RSCP.

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Idle Mode and Common Channel Behavior

52

qHyst2

Hysteresis value of the serving cell to be used for cell ranking based on CPICH Ec/No.

qOffset1sn

Signal strength offset between source and target cell to be used for cell ranking based on CPICH RSCP. The parameter is defined per WCDMA neighbor relation and per GSM neighbor relation.

qOffset2sn

Signal strength offset between source and target cell to be used for cell ranking based on CPICH Ec/No. The parameter is defined per WCDMA neighbor relation.

qQualMin

Minimum required quality level in the cell measured in the UE. The parameter is defined per serving cell and per WCDMA neighbor.

qRxLevMin

Minimum signal strength level received in the UE. The parameter is defined per serving cell and per WCDMA neighbor and GSM neighbor.

qualityOffset

An additional offset applied to cells belonging to the MBMS Preferred Layer. The parameter is defined per cell and signalled to the UE on the MBMS control channel MCCH.

qualMeasQuantity

Quality measure (CPICH RSCP or CPICH Ec/No) used in UE functions for cell selection and reselection in Idle and Connected modes. The parameter is defined per cell.

sHcsRat

Decision on when measurements on GSM neighbors are performed which is made using this parameter in relation with Srxlev. The parameter is defined per cell.

sInterSearch

Decision on when measurements on Interfrequency neighbors are performed. The parameter is defined per cell.

sIntraSearch

Decision on when measurements on Intrafrequency neighbors are performed. The parameter is defined per cell.

sRatSearch

Decision on when measurements on GSM neighbors are performed which is made using this parameter in relation with Squal. The parameter is defined per cell.

treSelection

Reselection time control of cell selection and reselection. The time-to-trigger for cell reselection occurs in seconds. The parameter is defined per cell.

uarfcnDl

Downlink UTRAN Absolute Radio Frequency Channel number. Specifies the channel number for the central

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Parameters

DL frequency. The mapping from channel number to physical frequency is described in 3GPP specification TS 25.104. uarfcnUl

5.1.2

5.1.3

Location and Routing Area Updating att

Parameter that facilitates the avoidance of unnecessary paging attempts. The parameter is sent on BCCH and informs the UE if IMSI attach and detach is applied. It is defined per Location Area.

lAC

LA Code that identifies a Location Area.

rAC

RA Code that identifies a Routing area.

t3212

Periodic Update Timer for LA update. The parameter is defined per Location Area.

URA Handling uraIdentity

5.1.4

Uplink UTRAN Absolute Radio Frequency Channel number. Specifies the channel number for the central UL frequency. The mapping from channel number to physical frequency is described in 3GPP specification TS 25.104.

The parameter identifies a UTRAN Registration Area (URA) in the network.

Paging cnDrxCycleLength Cs

CN DRX cycle length coefficient (k) for UEs in Idle mode, circuit-switched. The parameter is defined per RNC.

cnDrxCycleLength Ps

CN DRX cycle length coefficient (k) for UEs in Idle mode, packet-switched. The parameter is defined per RNC.

utranDrxCycleLen gth

DRX cycle length coefficient (k) for paging of Connected mode UEs in state URA_PCH, applicable for both UTRAN and CN initiated paging. The parameter is defined per RNC.

noOfMaxDrxCycles

Paging notification duration. For notifying UEs in Idle mode about a system information update, the RNC sends a paging message on the PCH at every page occasion of a number of maximum DRX cycles. The parameter is defined per RNC.

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Idle Mode and Common Channel Behavior

noOfPagingRecord Transm

5.1.5

54

Number of preconfigured subsequent transmissions of the same paging record. The parameter is defined per RNC.

System Information noOfMibValueTag Retrans

Number of MIB value tag retransmissions on the FACH. The parameter is defined per RNC.

sb1RepPeriod

Repetition period for Scheduling Block 1. The parameter is defined per RNC.

sb1StartPos

Start position of Scheduling Block 1. The parameter is defined per RNC.

schedulingBlockE nabled

Controls whether the Scheduling Block (SB1) is being broadcasted or not.

sib1PLMNScopeValueTag

Area part of PLMN scope value tags for SIB1. The parameter is defined per cell.

sib1RepPeriod

Repetition period for SIB Type 1. The parameter is defined per RNC.

sib2RepPeriod

Repetition period for SIB Type 2. The parameter is defined per RNC.

sib3RepPeriod

Repetition period for SIB Type 3. The parameter is defined per RNC.

sib5RepPeriod

Repetition period for SIB Type 5 and SIB Type 5bis. The parameter is defined per RNC.

sib7RepPeriod

Repetition period for SIB Type 7. The parameter is defined per RNC.

sib11RepPeriod

Repetition period for SIB Type 11. The parameter is defined per RNC.

sib12RepPeriod

Repetition period for SIB Type 12. The parameter is defined per RNC.

sib18RepPeriod

Repetition period for SIB Type 18. The parameter is defined per RNC.

sib1StartPos

Start position of SIB Type 1. The parameter is defined per RNC.

sib2StartPos

Start position of SIB Type 2. The parameter is defined per RNC.

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Parameters

5.1.6

5.2

sib3StartPos

Start position of SIB Type 3. The parameter is defined per RNC.

sib5StartPos

Start position of SIB Type 5 and SIB Type 5bis. The parameter is defined per RNC.

sib7StartPos

Start position of SIB Type 7. The parameter is defined per RNC.

sib11StartPos

Start position of SIB Type 11. The parameter is defined per RNC.

sib12StartPos

Start position of SIB Type 12. The parameter is defined per RNC.

sib18StartPos

Start position of SIB Type 18. The parameter is defined per RNC.

sib7expirationTime Factor

SIB7 use expiration time as reread mechanism. The expiration time is parameter sib7RepPeriod times the sib7expirationTimeFactor. The parameter is defined per RNC.

updateCellReattsN o

Number of update reattempts when an update of system information parameters in a cell failed. The parameter is defined per RNC.

Load-triggered Access Class Barring iuSccpConRateMe asPeriod

Averaging period for Iu-signalling connection setup rate measurement used for Load-triggered Access Class Barring and PDF counter pmIuSccpConRate.

iuSccpConRateThr esh

Connection setup rate threshold for Load-triggered Access Class Barring. Iu-signalling connection setup rate is averaged over period of iuSccpConRateMea sPeriod. If the average exceeds this threshold, the Load-triggered Access Class Barring is triggered and 80% of the Access Classes in range [0; 9] are randomly barred in the entire RNS. The access restrictions are removed in the following measurement periods, in step of 2 Access Classes at the time, if the connection setup rate in that period has been reduced below this threshold (adjusted by an internal hysteresis margin of 20%).

Values and Ranges Table 6 on page 56 specifies the parameters described in this document.

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Idle Mode and Common Channel Behavior

Table 6

WCDMA RAN Idle Mode Parameters

Parameter Name

Default Value

Value Range

Resolut ion

Unit

FALSE

FALSE; TRUE

-

-

[No access restrictions apply for Access Classes 0 to 15 (n= 0..15)]

[Each boolean in the vector represents one Access Class: FALSE = No access restrictions apply for this Access Class; TRUE = access restrictions apply for this Access Class]

[-]

[-]

FALSE

FALSE; TRUE

-

-

[No CS domain specific access restric tion apply for Access Classes 0 to 15 (n= 0..15)]

[Each boolean in the vector represents one Access Class: FALSE = No CS domain specific access restrictions apply for this Access Class; TRUE = CS domain specific access restrictions apply for this Access Class]

[-]

[-]

FALSE

FALSE; TRUE

-

-

[No PS domain specific access restric tion apply for Access Classes 0 to 15 (n= 0..15)]

[Each boolean in the vector represents one Access Class: FALSE = No PS domain specific access restrictions apply for this Access Class; TRUE = PS domain specific access restrictions apply for this Access Class]

[-]

[-]

bandIndicator

DCS 1800

DCS 1800; PCS 1900; OTHER_BANDS

-

-

bcchFrequency

-

0..1023

1

-

Cell Selection and Reselection accessClassNBarred[n]

accessClassesBarredCs[n]

accessClassesBarredPs[n]

56

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Parameters

Table 6

WCDMA RAN Idle Mode Parameters

Parameter Name cellReserved

Default Value

Value Range

Resolut ion

Unit

NOT_RESE RVED

RESERVED; NOT_RESERVED

-

-

0

0..12

1

-

[0]

[0: not broadcasted in SIB 11 (UE is not allowed to leave SCCPCH to perform measurements on other frequencies or RATs)

[-]

[-]

fachMeasOccaCycLenCoeff

1: not used 2: not used 3: used when inter-frequency and GSM neighbors are configured in the cell 4: used when inter-frequency or GSM neighbors are configured in the cell 5-12: not used] hcsSib3Config.hcsPrio

0

0..7

1

-

hcsSib3Config.qHcs

0

0..99

1

-

[CPICH Ec/N0 mapping: -24]

[CPICH Ec/N0 mapping: 0..48 = -24..0; 49..99 = spare]

[0.5]

[dB]

[CPICH RSCP mapping: -115]

[CPICH RSCP mapping: 0..89 = -115..-26; 89..99 = spare]

[1]

[dB]

-105

-105 .. 91

2

dB

hcsSib11Config.hcsPrio

0

0..7

1

-

hcsSib11Config.penaltyTime

0

0..60

10

-

[not used]

[not used, 10, 20, 30, 40, 50, 60]

[-]

[s]

hcsSib3Config.sSearchHcs

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Idle Mode and Common Channel Behavior

Table 6

WCDMA RAN Idle Mode Parameters

Parameter Name

Default Value

Value Range

Resolut ion

Unit

0

0..99

1

-

[CPICH Ec/N0 mapping: -24]

[CPICH Ec/N0 mapping: 0..48 = -24..0; 49..99 = spare]

[0.5]

[dB]

[CPICH RSCP mapping: -115]

[CPICH RSCP mapping: 0..89 = -115..-26; 89..99 = spare]

[1]

[dB]

0..21

3

dB

[infinity; 3; 6; 9; 6; 12; 15; 18; 21]

[-]

[dB]

0; 2; 3; 4; 6; 8; 10; 12

-

dB

[infinity]

[infinity; 2; 3; 4; 6; 8; 10; 12]

[-]

[dB]

FALSE

FALSE; TRUE

-

-

hcsSib11Config.qHcs

hcsSib11Config.temporaryOffset1 0 [infinity] hcsSib11Config.temporaryOffset2 0

hcsUsage.connectedMode

Note 2 hcsUsage.idleMode hcsPrioOffset interFreqFddMeasIndicator

FALSE

FALSE; TRUE

-

-

7

0..7

1

-

FALSE

FALSE; TRUE

-

-

maxTxPowerUl (serving cell, WCDMA neighbor-50..+33 within same RNC) 24 1

dBm

maxTxPowerUl (WCDMA neighbor 100 belonging-50..+33; to another RNC) 100 (100: The parameter is not sent in SIB11 and the UE will use the same value as specified for maxTxPowerUl in serving cell)

1

dBm

maxTxPowerUl (GSM neighbor)

mcc

58

100

-50..+33; 100 (100: The parameter is not sent in SIB11 and the UE will use the maximum output power for this GSM cell, according to its radio access capability)

1

dBm

1

0..999

1

-

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Parameters

Table 6

WCDMA RAN Idle Mode Parameters

Parameter Name

Default Value

Value Range

Resolut ion

Unit

mnc

1

0..999

1

-

nmo

MODE_II

MODE_I; MODE_II

-

-

primaryScramblingCode

-

0..511

1

-

qHyst1

4

0..40

2

dB

qHyst2

4

0..40

2

dB

qOffset1sn (WCDMA neighbor relation) 0

-50..50

1

dB

qOffset1sn (GSM neighbor relation) 7

-50..50

1

dB

qOffset2sn (WCDMA neighbor relation) 0

-50..50

1

dB

qQualMin (serving cell, WCDMA -18 neighbor within same RNC) -24..0

1

dB

qQualMin (WCDMA neighbor belonging to -24..0; another RNC)The 100 100 (100: parameter is not sent in SIB11 and the UE will use the same value as specified for qQualMin in serving cell)

1

dB

qRxLevMin (serving cell, WCDMA neighbor belonging -115 -119..-25 to same 2RNC)

dBm

Note 1 qRxLevMin (WCDMA neighbor belonging to-119..-25; another RNC) 100 100 (100: The parameter is not sent in SIB11 and the UE will use the same value as specified for qRxLevMin in serving cell)

2

dBm

Note 1 qRxLevMin (GSM neighbor)

qualityOffset

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100

-115..-25; 100 (100: The parameter is not sent in SIB11 and the UE will use same value as specified for qRxlevMin in serving cell)

2

dBm

-1

- 1; 4; 8; 12; 16; 20; 30; 40

-

dB

[infinity]

[infinity; 4; 8; 12; 16; 20; 30; 40]

[-]

[dB]

59


Idle Mode and Common Channel Behavior

Table 6

WCDMA RAN Idle Mode Parameters

Parameter Name

Default Value

Value Range

Resolut ion

Unit

CPICH_EC _N0

CPICH_RSCP; CPICH_EC_N0

-

-

- 105

-105..91 (A negative value is interpreted as 0 by the UE)

2

dB

0

0; 1..27

1

2 dB

[0]

[not sent; -32..20]

[2]

[dB]

0

0; 1..27

1

2 dB

[0]

[not sent; -32..20]

[2]

[dB]

sRatSearch

4

-32..20 (A negative value is interpreted as 0 by the UE)

2

dB

treSelection

2

0..31

1

s

uarfcnDl

-

0..16383

-

-

uarfcnUl

-

0..16383

-

-

att

TRUE

FALSE; TRUE

-

-

lAC

-

1..65533; 65535

1

-

rAC

-

0..255

1

-

10

0; 1..255

1

6 min

[60]

[infinite; 6..1530]

[6]

[min]

-

0..65535

1

-

6

6..9

1

10(2^k) ms

[640]

[640; 1280; 2560; 5120]

[-]

[ms]

7

6..9

1

10(2^k) ms

[1280]

[640; 1280; 2560; 5120]

[-]

[ms]

qualMeasQuantity sHcsRat

sInterSearch sIntraSearch

Location and Routing Area Updating

t3212 URA Handling uraIdentity Paging cnDrxCycleLengthCs

cnDrxCycleLengthPs

60

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Parameters

Table 6

WCDMA RAN Idle Mode Parameters

Parameter Name

Default Value

Value Range

Resolut ion

Unit

5

3..9

1

[320]

[80; 160; 320; 640; 1280; 2560; 5120]

[-]

10(2^k) ms

utranDrxCycleLength

[ms]

noOfMaxDrxCycles

1

1..10

1

-

noOfPagingRecordTransm

2

1..5

1

-

0

0..10

1

-

sb1RepPeriod

128

4, 8, 16, 32, ..., 4096

-

SFN

sb1StartPos

126

0..4094

2

SFN

FALSE

FALSE; TRUE

-

-

-

0..31

1

-

sib1RepPeriod

32

4, 8, 16, 32, ..., 4096

-

SFN

sib2RepPeriod

128

4, 8, 16, 32, ..., 4096

-

SFN

sib3RepPeriod

16

4, 8, 16, 32, ..., 4096

-

SFN

sib5RepPeriod

32

4, 8, 16, 32, ..., 4096

-

SFN

sib7RepPeriod

16

4, 8, 16, 32, ..., 4096

-

SFN

sib11RepPeriod

128

4, 8, 16, 32, ..., 4096

-

SFN

sib12RepPeriod

32

4, 8, 16, 32, ..., 4096

-

SFN

sib18RepPeriod

128

4, 8, 16, 32, ..., 4096

-

SFN

sib1StartPos

4

0..4094

2

SFN

sib2StartPos

118

0..4094

2

SFN

sib3StartPos

2

0..4094

2

SFN

sib5StartPos

6

0..4094

2

SFN

sib7StartPos

2

0..4094

2

SFN

sib11StartPos

20

0..4094

2

SFN

sib12StartPos

14

0..4094

2

SFN

sib18StartPos

122

0..4094

2

SFN

sib7ExpirationTimeFactor

1

1, 2, 4, 8, ..., 256

-

times

updateCellReattsNo

5

0..10

1

-

System Information noOfMibValueTagRetrans

schedulingBlockEnabled sib1PlmnScopeValueTag

Load-triggered Access Class Barring

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Idle Mode and Common Channel Behavior

Table 6

WCDMA RAN Idle Mode Parameters

Parameter Name iuSccpConRateMeasPeriod iuSccpConRateThresh

Default Value

Value Range

Resolut ion

Unit

120

10..120

10

s

10000

10..10000

10

connecti ons/s

Note 1: Support for values below -115 dB is introduced with the optional feature Increased Downlink Coverage. This is a license controlled feature, and a software key is necessary for activation. For more information see Handling of License Control. Note 2: In order for the UE to apply HCS rules in connected mode the corresponding parameter for idle mode (hcsUsage.idleMode ) must also be set to TRUE. Recommended setting of the parameters listed in the table above can be found in Radio Network Parameters, 86/1553 - HSD 101 02/6.

62

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Reference List

Reference List

[1]

GSM-UMTS Cell Reselection and Handover, User Description, 208/1553-HSC 103 12/11

[2]

Technical Specification, NAS Functions related to Mobile Station (MS) in idle mode, 3GPP TS 23.122

[3]

UE Procedures in Idle Mode and Procedures for Cell Reselection in Connected Mode, 3GPP TS 25.304

[4]

Radio Resource Control (RRC) Protocol Specification, 3GPP TS 25.331

[5]

Service Accessibility, 3GPP TS 22.011

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Idle mode