Wcdma Ran Planning And Optimization Features And Algorithms _2.Pdf

Microsoft PowerPoint WCDMA UE Behaviors in Idle Mode RAN6 www huawei com Copyright © 2008 Huawei Technologies Co , Ltd All rights reserved WCDMA UE Behaviors in Idle Mode 1 Page1Copyright © 2008 Huawe[.]

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WCDMA UE Behaviors

in Idle Mode

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Foreword

z UE behaviors in idle mode include :

PLMN selection

System information reception

Cell selection and reselection

Location registration

Paging procedure

Access procedure

z PLMN selection

Used to ensure that the PLMN selected by the UE properly provides services

z Cell selection and reselection

Used to ensure that the UE finds a suitable cell to camp on

z Location registration

Used for the network to trace the current status of the UE and to ensure that the UE is camped

on the network when the UE does not perform any operation for a long period

z System information reception

The network broadcasts the network information to a UE which camps on the cell to control the behaviors of the UE

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Contents

1 PLMN Selection

2 System Information Reception

3 Cell Selection and Reselection

4 Location Registration

5 Paging Procedure

6 Access Procedure

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Contents

1 PLMN Selection

5 Paging Procedure

6 Access Procedure

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Cell Search

z UE does not have UTRAN carrier information

In order to find a suitable cell to stay, UE will scan all the frequencies in UTRAN In each carrier, UE just need to find a cell with best signal

z UE has UTRAN carrier information

UE will try whether the original cell is suitable to stay If not, UE still need to scan all the frequencies about UTRAN in order to find a suitable cell in PLMN

z Typical scenario of first occasion is the first time a new UE is put into use

z The second occasion is very common

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z Step 1: Slot synchronization

During the first step of the cell search procedure the UE uses the primary synchronisation code (PSC) to acquire slot synchronisation to a cell

z Step 2: Frame synchronization and code-group identification

During the second step of the cell search procedure, the UE uses the secondary

synchronisation code (SSC) to find frame synchronisation and identify the code group of the cell found in the first step

z Step 3: Primary Scrambling code identification:

During the last step of the cell search procedure, the UE determines the exact primary

scrambling code used by the found cell The primary scrambling code is typically identified through symbol-by-symbol correlation over the CPICH with all codes within the code group identified in the second step

z If the UE has received information about which scrambling codes to search for, steps 2 and 3 above can be simplified

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PLMN Selection

z UE shall maintain a list of allowed PLMN types In the

PLMN list, the UE arranges available PLMNs by priorities When selecting a PLMN, it searches the PLMNs from the

high priority to the low

z The UE selects a PLMN from HPLMNs or VPLMNs

z UE can get the system information from PCCPCH, and the PLMN information is transmitted in MIB of PCCPCH

z After getting the MIB, UE can judge weather the current PLMN is the right one If so, UE will get the SIB scheduling information from the MIB; if not, UE will search another carrier, do this procedure again

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PLMN Selection (Cont.)

z PLMN Selection in HPLMNs

Automatic PLMN Selection Mode

The UE selects an available and suitable PLMN from the whole band according to the priority order

Manual PLMN Selection Mode

The order of manual selection is the same as that of automatic selection

z The priority order for automatic PLMN selection mode

The PLMN selected by the

UE before automatic PLMN selection

Previously selected PLMN6

The PLMNs are arranged in descending order of signal quality

Other PLMN/access technology combinations excluding the previously selected PLMN5

The PLMNs are arranged in random order

Other PLMN/access technology combinations with the high quality of received signals excluding the previously selected PLMN

Home PLMNsHPLMNs

1

Remark PLMN type

Order

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z A value of T minutes may be stored in the SIM T is either in the range from 6 minutes to 8 hours in 6-minute steps or it indicates that no periodic attempts shall be made If no value is stored in the SIM, a default value of 60 minutes is used

z After the UE is switched on, a period of at least 2 minutes and at most T minutes shall elapse before the first attempt is made

z The UE shall make an attempt if the UE is on the VPLMN at time T after the last attempt

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Contents

1 PLMN Selection

2 System Information Reception

5 Paging Procedure

6 Access Procedure

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Structure of System Information

z System information is organized as a tree, including:

MIB (Master Information Block )

SB (Scheduling Block )

SIB (System Information Block )

z System information is used for the network to broadcast network information to UEs camping

on a cell so as to control the behavior of UEs

z MIB

When selecting a new cell, the UE reads the MIB The UE may locate the MIB by predefined scheduling information The IEs in the MIB includes MIB value tag, PLMN type, PLMN identity, reference and scheduling information for a number of SIBs in a cell or one or two SBs in a cell

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System Information

z SIB1: Contains the system information for NAS and the

timer/counter for UE

z SIB2: Contains the URA information

z SIB3: Contains the parameters for cell selection and cell

re-selection

z SIB5: Contains parameters for the common physical channels of the cell

z SIB7: Contains the uplink interference level and the refreshing

timer for SIB7

z SIB11: Contains measurement controlling information

z SIB4: Contains parameters for cell selection and cell re-selection while UE is in connected mode

z SIB6: Contains parameters for the common physical channels of the cell while UE is in

connected mode

z SIB8: Contains the CPCH static information

z SIB9: Contains the CPCH dynamic information

z SIB10: Contains information to be used by UEs having their DCH controlled by a DRAC procedure Used in FDD mode only To be used in CELL_DCH state only Changes so often, its decoding is controlled by a timer

z SIB12: Contains measurement controlling information in connecting mode

z SIB13: Contains ANSI-41 system information

z SIB14: Contains the information in TDD mode

z SIB15: Contains the position service information

z SIB16: Contains the needed pre-configuration information for handover from other RAT to UTRAN

z SIB17: Contains the configuration information for TDD

z SIB18: Contains the PLMN identities of the neighboring cells

To be used in shared networks to help with the cell reselection process

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Reception of System Information

z The UE shall read system information broadcast on a BCH transport channel when the UE is in idle mode or in

connected mode, that is, in CELL_FACH, CELL_PCH, or

URA_PCH state

z The UE may use the scheduling information in MIB and SB to locate each SIB to be acquired

If the UE receives a SIB in a position according to the scheduling information and consider the content valid, it will read and store it

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Contents

1 PLMN Selection

3 Cell Selection and Reselection

5 Paging Procedure

6 Access Procedure

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Cell Selection

z When the PLMN is selected and the UE is in idle mode, the

UE starts to select a cell to camp on and to obtain services

z There are four states involved in cell selection:

Camped normally

Any cell selection

Camped on any cell

Connected mode

z Camped normally: The cell that UE camps on is called the suitable cell In this state, the UE obtains normal service

z Any cell selection: In this state, the UE shall attempt to find an acceptable cell of an any PLMN

to camp on, trying all RATs that are supported by the UE and searching first for a high quality cell

z Camped on any cell: The cell that UE camps on is called the acceptable cell In this state the

UE obtains limited service The UE shall regularly attempt to find a suitable cell of the selected PLMN, trying all RATs that are supported by the UE

z Connected mode: When returning to idle mode, the UE shall use the procedure Cell selection when leaving connected mode in order to find a suitable cell to camp on and enter state Camped normally If no suitable cell is found in cell reselection evaluation process, the UE enters the state Any cell selection

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Cell Selection (Cont.)

z Two types of cell selection:

Initial cell selection

If no cell information is stored for the PLMN, the UE starts this procedure

Stored information cell selection

If cell information is stored for the PLMN, the UE starts this procedure

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

z Stored information cell selection: For this procedure, the UE need know the central frequency information and other optional cell parameters that are obtained from the measurement control information received before, such as scrambling codes After this procedure is started, the UE selects a suitable cell if it finds one Otherwise, the "Initial cell selection" procedure is triggered

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Cell Selection Criteria

min

qual qualmeas

on compensati rxlev

rxlevmeas

z Criterion S is used by the UE to judge whether the cell is

suitable to camped on.

z Criterion S : Srxlev > 0 & Squal > 0 , where:

z If the pilot strength and quality of one cell meet S criteria, UE will stay in this cell and get other system information Then, UE will initiate a location update registration process

z If the cell doesn’t satisfy S criteria, UE will get adjacent cells information from SIB11 Then, UE will judge weather these cells satisfy S criteria If the adjacent cell is suitable, UE will stay in the adjacent cell

z If no cell satisfies S criteria, UE will take the area as dead zone and continue the PLMN selection and reselection procedure

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Parameters of S Criterion

Parameter name: Cell Se-reselection quality measure

Recommended value: CPICH_ECNO

Parameter name: Min quality level

Recommended value: -18, namely -18dB

z QUALMEAS

Parameter name: Cell Sel-reselection quality measure

Value range: CPICH_ECNO(CPICH Ec/N0),CPICH_RSCP(CPICH RSCP)

Physical unit: None

Content: Cell selection and reselection quality measure, may be set to CPICH Ec/N0

Set this parameter through ADD CELLSELRESEL, query it through LST

CELLSELRESEL, and modify it through MOD CELLSELRESEL

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Parameters of S Criterion

Parameter name: Min Rx level

Recommended value: -58, namely -115dBm

Parameter name: Max allowed UE UL TX power

Recommended value: 21, namely 21dBm

Recommended value: -58

Recommended value: -21

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Measurement Start Criteria (Cont.)

Qqualmeas ≤ Qqualmin+ Sintrasearch

z Parameters of the measurement start criteria

Minimum required quality level in the cell (dB)

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Qqualmeas ≤ Qqualmin+ Sintersearch

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Qqualmeas ≤ Qqualmin+ SsearchRATm

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Parameters of Measurement Start Criteria

Recommended value: None

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Parameter name: Inter-RAT cell reselection threshold

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Measurement Start Criteria Description

z The intra-frequency, inter-frequency, and inter-RAT measurement criteria are as shown in the figure

z Usually, Sintrasearch > Sintersearch > SsearchRATm

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Cell Reselection Criteria

z Criterion R is used for intra-frequency, inter-frequency cells and inter-RAT cell reselection.

z The cell-ranking criterion R is defined by :

n s

offset n

z In Rs, s means serving cell In Rn, n means neighbor cell

z The offset Qoffset1s,n is used for Qoffsets,n to calculate Rn The hysteresis Qhyst1s is used for Qhysts to calculate Rs

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

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

reselection is set to CPICH RSCP, the UE shall reselect that FDD cell

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

reselection is set to CPICH Ec/N0, the UE shall perform a second ranking of the FDD cells according to the R criteria specified above

In this case, however, the UE uses the measurement quantity CPICH Ec/N0 for deriving the

Qmeas,n and Qmeas,s and then calculating the R values of the FDD cells The offset

Qoffset2s,n is used for Qoffsets,n to calculate Rn, the hysteresis Qhyst2s is used for Qhysts to

calculate Rs

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Hysteresis and Time Interval

TimeTreselection

Quality

RnRsQmeas,n

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

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

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Parameters of R Criteria

Parameter name: Hysteresis 1 for idle mode

Recommended value: 2, namely 4dB

Parameter name: Hysteresis 1 for connect mode

Recommended value: 2, namely 4dB

Recommended value: 2

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Parameters of R Criteria (Cont.)

Parameter name: Hysteresis 2 for idle mode

Recommended value: Qhyst1s for idle mode

Parameter name: Hysteresis 2 for connected mode

Recommended value: Qhyst1s for connected mode.

Content: The hysteresis value in idle mode for serving FDD cells in case the quality

measurement for cell selection and reselection is set to CPICH Ec/No It is related to the slow fading feature of the area where the cell is located The greater the slow fading variance is, the greater this parameter It is optional If it is not configured, [Hysteresis 1] will be adopted as the value

Recommended value: Qhyst1s for idle mode

Set this parameter through ADD CELLSELRESEL, query it through LST CELLSELRESEL, and modify it through MOD CELLSELRESEL

Content: The hysteresis value in connect mode for serving FDD cells in case the quality

measurement for cell selection and reselection is set to CPICH RSCP It is related to the slow fading feature of the area where the cell is located The greater the slow fading variance is, the greater this parameter

Recommended value: Qhyst1s for connected mode

Set this parameter through ADD CELLSELRESEL, query it through LST CELLSELRESEL, and modify it through MOD CELLSELRESEL

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Parameter name: Reselection delay time

Recommended value: 1, namely 1s.

to avoid ping-pong reselection between different cells Note: The value 0 corresponds

to the default value defined in the protocol

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Parameter name: IdleQoffset1sn

Recommended value: 0, namely 0dB.

Parameter name: ConnQoffset1sn

z IDLEQOFFSET1SN

Offset of cell CPICH RSCP measurement value in cell selection or reselection when the UE is in idle mode

z CONNQOFFSET1SN

Offset of cell CPICH RSCP measurement value in cell selection or reselection when the UE is in connected mode

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z IDLEQOFFSET2SN

Offset of cell CPICH Ec/No measurement value in cell selection or reselection when the UE is in idle mode

z CONNQOFFSET2SN

Offset of cell CPICH RSCP measurement value in cell selection or reselection when the UE is in connected mode

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Contents

1 PLMN Selection

4 Location Registration

5 Paging Procedure

6 Access Procedure

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Location Registration

z The location registration includes:

Location update (for non-GPRS)

Route update (for GPRS)

z The location registration is used for the PLMN to trace the current status of the UE and to ensure that the UE is connected with the network when the UE does not perform any operation for a long period

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Periodic Location Registration

z Periodic location registration is controlled by a Periodic

Location Update timer (T3212) or a Periodic Routing Area Update timer (T3312)

z Periodic location registration may be used to periodically notify the network of the availability of the UE

z T3212 is for non-GPRS operation

z T3312 is for GPRS operation

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Parameters of Location Registration

Parameter name: Periodical location update timer [6min]

Recommended value: 10, namely 60min

z ATT

Parameter name: Attach/detach indication

Recommended value: ALLOWED

z T3212

Parameter name: Periodical location update timer [6min]

Value range: 0~255

Physical unit: 6 min

Content: This parameter indicates the time length of the periodical location update Periodical location update is implemented by MS through the location update

procedure 0: The periodical update procedure is not used This parameter is valid only when [CN domain ID] is set as CS_DOMAIN

Set this parameter through ADD CNDOMAIN, query it through LST CNDOMAIN, modify it through MOD CNDOMAIN

z ATT

Parameter name: Attach/detach indication

Value range: NOT_ALLOWED, ALLOWED

Content: NOT_ALLOWED indicates that MS cannot apply the IMSI attach/detach procedure ALLOWED indicates that MS can apply the IMSI attach/detach procedure This parameter is valid only when [CN domain ID] is set as CS_DOMAIN

Recommended value: ALLOWED

Set this parameter through ADD CNDOMAIN, query it through LST CNDOMAIN, modify it through MOD CNDOMAIN

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Contents

1 PLMN Selection

5 Paging Procedure

6 Access Procedure

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Paging Initiation

z CN initiated paging

z Establish a signaling connection

z UTRAN initiated paging

z Trigger the cell update procedure

z Trigger reading of updated system information

z For CN originated paging:

In order to request UTRAN connect to UE, CN initiates the paging procedure,

transmits paging message to the UTRAN through Iu interface, and UTRAN transmits the paging message from CN to UE through the paging procedure on Uu interface, which will make the UE initiate a signaling connection setup process with the CN

z For UTRAN originated paging:

When the cell system message is updated: When system messages change, the UTRAN will trigger paging process in order to inform UE in the idle, CELL_PCH or URA_PCH state to carry out the system message update, so that the UE can read the updated system message

UE state transition: In order to trigger UE in the CELL_PCH or URA_PCH state to carry out state transition (for example, transition to the CELL_FACH state), the UTRAN will perform a paging process Meanwhile, the UE will initiate a cell update or URA update process, as a reply to the paging

Tiêu đề	Wcdma Ue Behaviors In Idle Mode
Trường học	Huawei Technologies Co., Ltd.
Chuyên ngành	Telecommunications
Thể loại	Báo cáo
Năm xuất bản	2008
Thành phố	Shenzhen

Định dạng
Số trang	495
Dung lượng	6,68 MB

Wcdma Ran Planning And Optimization Features And Algorithms _2.Pdf

Intra-Frequency Handover Decision and Execution