56699897 wcdma ran planning and optimization features and algorithms 130624140125 phpapp02

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Copyright 2008 Huawei Technologies Co., Ltd. All rights reserved.

WCDMA UE Behaviors in Idle Mode

1


Forewordz UE behaviors in idle mode include :

PLMN selection

System information reception

Cell selection and reselection

Location registration

Paging procedure

Access procedure

z PLMN selectionUsed to ensure that the PLMN selected by the UE properly provides services.

z Cell selection and reselectionUsed to ensure that the UE finds a suitable cell to camp on.

z Location registrationUsed 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 receptionThe network broadcasts the network information to a UE which camps on the cell to control the behaviors of the UE.

z PagingUsed for the network to send paging messages to a UE which is in idle mode, CELL_PCH state, or URA_PCH state.

z AccessFrom the view of access stratum, access is the procedure UE shift from idle mode to connected mode.

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Contents1. PLMN Selection

2. System Information Reception

3. Cell Selection and Reselection

4. Location Registration

5. Paging Procedure

6. Access Procedure

3






5. Paging Procedure

6. Access Procedure

4


Cell Searchz 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.

5


Cell Search

Slot synchronization

Frame synchronization and code-group identification

Primary Scrambling code identification

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 identificationDuring 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.

6


PLMN Selectionz 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

7


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

4

The PLMNs are arranged in priority order

PLMNs contained in the "Operator Controlled PLMN Selector with Access Technology" data field in the SIM excluding the previously selected PLMN

3

The PLMNs are arranged in priority order

PLMNs contained in the "User Controlled PLMN Selector with Access Technology" data field in the SIM excluding the previously selected PLMN

2

Home PLMNsHPLMNs1

RemarkPLMN typeOrder

8


PLMN Selection (Cont.)z PLMN Selection in VPLMNs

If a UE is in a VPLMN, it scans the user controlled PLMN

selector field or the operator controlled PLMN selector field

in the PLMN list to find the HPLMN or the PLMN with higher

priority according to the requirement of the automatic PLMN

selection mode.

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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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.

z SB Scheduling Block (SB) gives reference and scheduling information to other SIBs. The

scheduling information of a SIB may be included in only one of MIB and SB.z SIB

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

z Scheduling information for a system information block may only be included in either the master information block or one of the scheduling blocks.

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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 refreshingtimer 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 informationz SIB9: Contains the CPCH dynamic informationz 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 modez SIB13: Contains ANSI-41 system informationz SIB14: Contains the information in TDD modez SIB15: Contains the position service informationz SIB16: Contains the needed pre-configuration information for handover from other RAT to

UTRANz SIB17: Contains the configuration information for TDDz 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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5. Paging Procedure

6. Access Procedure

14


Cell Selectionz 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.

15


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

minqualqualmeasqual QQS =oncompensatirxlevrxlevmeasrxlev PQQS = min

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 doesnt 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.

MaxUE_TXPWR_MAX_RACH-P_MAX0, dBmPcompensationMaximum TX power level an UE may use when accessing the cell on RACH (read in system information) (dBm)

UE_TXPWR_MAX_RACH

Maximum RF output power of the UE (dBm)P_MAX

Minimum required RX level in the cell (dBm)Qrxlevmin

Minimum required quality level in the cell (dB)Qqualmin

Measured cell RX level value. This is received signal, CPICH RSCP for current cells (dBm)

Qrxlevmeas

Measured cell quality value. The quality of the received signal expressed in CPICH Ec/N0 (dB) for current cell

Qqualmeas

Cell RX level value (dBm)Srxlev

Cell quality value (dB)Squal

ExplanationParameters

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Parameters of S Criterionz QUALMEAS

Parameter name: Cell Se-reselection quality measure

Recommended value: CPICH_ECNO

z QQUALMIN

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

or CPICH RSCP. Recommended value: CPICH_ECNO.

z QQUALMIN Parameter name: Min quality level Value range: -24~0 Physical value range: -24~0; step: 1 Physical unit: dB Content: The minimum required quality level corresponding to CPICH Ec/No. The UE

can camp on the cell only when the measured CPICH Ec/No is greater than the value of this parameter.

Recommended value: -18 Set this parameter through ADD CELLSELRESEL, query it through LST

CELLSELRESEL, and modify it through MOD CELLSELRESEL.

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Parameters of S Criterionz QRXLEVMIN

Parameter name: Min Rx level

Recommended value: -58, namely -115dBm

z MAXALLOWEDULTXPOWER

Parameter name: Max allowed UE UL TX power

Recommended value: 21, namely 21dBm

z QRXLEVMIN Parameter name: Min Rx level Value range: -58~-13. Physical value range: -115~-25; step: 2 (-58:-115; -57:-113; ..., -13:-25 ). Physical unit: dBm. Content: The minimum required RX level corresponding to CPICH RSCP. The UE can

camp on the cell only when the measured CPICH RSCP is greater than the value of this parameter.

Recommended value: -58. Set this parameter through ADD CELLSELRESEL, query it through LST

CELLSELRESEL, and modify it through MOD CELLSELRESEL.z MAXALLOWEDULTXPOWER

Parameter name: Max allowed UE UL TX power Value range: -50~33 Physical value range: -50~33; step: 1 Physical unit: dBm Content: The maximum allowed uplink transmit power of a UE in the cell, which is

related to the network planning. Content: Allowed maximum power transmitted on RACH in the cell. It is related to network planning.

Recommended value: -21 Set this parameter through ADD CELLSELRESEL, query it through LST


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Cell Reselectionz After selecting a cell and camping on it, the UE periodically

searches for a better cell according to the cell reselection

criteria. If finding such a cell, the UE selects this cell to

camp on.

z UE should monitor the quality of current cell and neighbor cells in order to camp on the better cell to initiate service. The better cell is the most suitable one for the UE to camp on and obtain services. The QoS of this cell is not necessarily more satisfying.

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Measurement Start Criteria (Cont.)z Intra-frequency measurement

Squal Sintrasearch

Qqualmeas Qqualmin Sintrasearch

Qqualmeas Qqualmin + Sintrasearch

z Parameters of the measurement start criteria

Minimum required quality level in the cell (dB) .Qqualmin

Measurement threshold for UE to trigger inter-RAT cell reselection, compared with Squal.

SsearchRATm

Measurement threshold for UE to trigger inter-frequency cell reselection, compared with Squal.

Sintersearch

Measurement threshold for UE to trigger intra-frequency cell reselection, compared with Squal.

Sintrasearch


DescriptionName

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Measurement Start Criteria (Cont.)z Inter-frequency measurement

Squal Sintersearch

Qqualmeas Qqualmin Sintersearch

Qqualmeas Qqualmin + Sintersearch




SsearchRATm


Sintersearch


Sintrasearch


DescriptionName

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Measurement Start Criteria (Cont.)z Inter-RAT measurement

Squal SsearchRATm

Qqualmeas Qqualmin SsearchRATm

Qqualmeas Qqualmin + SsearchRATm




SsearchRATm


Sintersearch


Sintrasearch


DescriptionName

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Parameters of Measurement Start Criteria

z IDLESINTRASEARCH

Parameter name: Intra-freq cell reselection threshold for idle

mode

Recommended value: None

z CONNSINTRASEARCH

Parameter name: Intra-freq cell reselection threshold for

connected mode


z IDLESINTRASEARCH Parameter name: Intra-freq cell reselection threshold for idle mode Value range: {{-16~10},{127}} . Physical value range: -32~20; step: 2. Physical unit: dB. Content: A threshold for intra-frequency cell reselection in idle mode. When the quality

(CPICH Ec/No measured by UE) of the serving cell is lower than this threshold plus the [Qqualmin] of the cell, the intra-frequency cell reselection procedure will be started.

Recommended value: None. Set this parameter through ADD CELLSELRESEL, query it through LST

CELLSELRESEL, and modify it through MOD CELLSELRESEL.z CONNSINTRASEARCH

Parameter name: Intra-freq cell reselection threshold for connected mode Value range: {{-16~10},{127}} . Physical value range: -32~20; step: 2. Physical unit: dB Content: A threshold for intra-frequency cell reselection in connect mode. When the

quality (CPICH Ec/No measured by UE) of the serving cell is lower than this threshold plus the [Qqualmin] of the cell, the intra-frequency cell reselection procedure will be started.



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z IDLESINTERSEARCH

Parameter name: Inter-freq cell reselection threshold for idle

mode


z CONNSINTERSEARCH

Parameter name: Inter-freq cell reselection threshold for

connected mode


z IDLESINTERSEARCH Parameter name: Inter-freq cell reselection threshold for idle mode Value range: {{-16~10},{127}} . Physical value range: -32~20; step: 2. Physical unit: dB. Content: A threshold for inter-frequency cell reselection in idle mode. When the quality

(CPICH Ec/No measured by UE) of the serving cell is lower than this threshold plus the [Qqualmin] of the cell, the inter-frequency cell reselection procedure will be started.


CELLSELRESEL, and modify it through MOD CELLSELRESEL.z CONNSINTERSEARCH

Parameter name: Inter-freq cell reselection threshold for connected mode Value range: {{-16~10},{127}} . Physical value range: -32~20; step: 2. Physical unit: dB Content: A threshold for inter-frequency cell reselection in connect mode. When the

quality (CPICH Ec/No measured by UE) of the serving cell is lower than this threshold plus the [Qqualmin] of the cell, the inter-frequency cell reselection procedure will be started.



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z SSEARCHRAT

Parameter name: Inter-RAT cell reselection threshold


z SSEARCHRAT Parameter name: Inter-RAT cell reselection threshold Value range: {{-16~10},{127}} . Physical value range: -32~20; step: 2. Physical unit: dB. Content: A threshold for inter-RAT cell reselection. When the quality (CPICH Ec/No

measured by UE) of the serving cell is lower than this threshold plus the [Qqualmin] of the cell, the inter-RAT cell reselection procedure will be started.



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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 Criteriaz Criterion R is used for intra-frequency, inter-frequency cells

and inter-RAT cell reselection.

z The cell-ranking criterion R is defined by :

nsoffsetnmeasnQQR

,,=

hystssmeass QQR += ,

z The cells are ranked according to R criteria specified above ,deriving QQmeas,nmeas,n and QQmeas,smeas,s and calculating R value.

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.

28


Hysteresis and Time Interval

TimeTreselection

Quality

Rn

Rs

Qmeas,n

Qmeas,s

Qhyst,s

Qoffsets,n

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

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

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Parameters of R Criteriaz IDLEQHYST1S

Parameter name: Hysteresis 1 for idle mode

Recommended value: 2, namely 4dB

z CONNQHYST1S

Parameter name: Hysteresis 1 for connect mode

Recommended value: 2, namely 4dB

z IDLEQHYST1S Parameter name: Hysteresis 1 for idle mode Value range: 0~20. Physical value range: 0~40; step: 2. Physical unit: dB. 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 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: 2. Set this parameter through ADD CELLSELRESEL, query it through LST

CELLSELRESEL, and modify it through MOD CELLSELRESEL.z CONNQHYST1S

Parameter name: Hysteresis 1 for connected mode Value range: 0~20. Physical value range: 0~40; step: 2. Physical unit: dB. 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.



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Parameters of R Criteria (Cont.)z IDLEQHYST2S

Parameter name: Hysteresis 2 for idle mode

Recommended value: Qhyst1s for idle mode

z CONNQHYST2S

Parameter name: Hysteresis 2 for connected mode

Recommended value: Qhyst1s for connected mode.

z IDLEQHYST2S Parameter name: Hysteresis 2 for idle mode Value range: {{0~20},{255}} . Physical value range: 0~40; step: 2. Physical unit: dB. 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.z CONNQHYST2S

Parameter name: Hysteresis 2 for connected mode Value range: {{0~20},{255}} . Physical value range: 0~40; step: 2. Physical unit: dB. 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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Parameters of R Criteria (Cont.)z TRESELECTIONS

Parameter name: Reselection delay time

Recommended value: 1, namely 1s.

z TRESELECTIONS Parameter name: Reselection delay time Value range: 0~31 . Physical value range: 0~31; step: 1. Physical unit: s. Content: If the signal quality of a neighboring cell is better than the serving cell during

the specified time of this parameter, the UE will reselect the neighboring cell. It is used 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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Parameters of R Criteria (Cont.)z IDLEQOFFSET1SN

Parameter name: IdleQoffset1sn

Recommended value: 0, namely 0dB.

z CONNQOFFSET1SN

Parameter name: ConnQoffset1sn


z IDLEQOFFSET1SN Parameter name: IdleQoffset1sn Offset of cell CPICH RSCP measurement value in cell selection or reselection when the UE is in

idle mode Value range: -50 to +50 . Physical value range: -50 to +50; step: 1. Physical unit: dB. Content: This parameter is used for moving the border of a cell. The larger the value of this

parameter, the lower the probability of neighboring cell selection. Recommended value: 0. Set this parameter through ADD INTRAFREQNCELL / ADD INTERFREQNCELL, query it

through LST INTRAFREQNCELL / LST INTERFREQNCELL, and modify it through MOD INTRAFREQNCELL / MOD INTERFREQNCELL.

z CONNQOFFSET1SN Parameter name: ConnQoffset1sn Offset of cell CPICH RSCP measurement value in cell selection or reselection when the UE is in

connected mode Value range: -50 to +50 . Physical value range: -50 to +50 ; step: 1. Physical unit: dB. Content: This parameter is used for moving the border of a cell. The larger the value of this



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Parameters of R Criteria (Cont.)z IDLEQOFFSET2SN

Parameter name: IdleQoffset2sn


z CONNQOFFSET2SN

Parameter name: ConnQoffset2sn


z IDLEQOFFSET2SN Parameter name: IdleQoffset2sn Offset of cell CPICH Ec/No measurement value in cell selection or reselection when the UE is in

idle mode Value range: -50 to +50 . Physical value range: -50 to +50; step: 1. Physical unit: dB. Content: This parameter is used for moving the border of a cell. The larger the value of this



z CONNQOFFSET2SN Parameter name: ConnQoffset2sn Offset of cell CPICH RSCP measurement value in cell selection or reselection when the UE is in

connected mode Value range: -50 to +50 . Physical value range: -50 to +50 ; step: 1. Physical unit: dB. Content: This parameter is used for moving the border of a cell. The larger the value of this



34






5. Paging Procedure

6. Access Procedure

35


Location Registrationz 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.

36


Periodic Location Registrationz 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 operationz T3312 is for GPRS operation

37


Parameters of Location Registration

z T3212

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.

Recommended value: 10. 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.

38






5. Paging Procedure

6. Access Procedure

39


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.

40


Paging Type 1z If UE is in CELL_PCH,URA_PCH or IDLE statethe paging

message will be transmitted on PCCH with paging type 1CN RNC1 RNC2 NODEB1.1 NODEB2.1 UE

RANAPRANAP

RANAP RANAP

PCCH: PAGING TYPE 1

PAGING

PAGING

PCCH: PAGING TYPE 1

z Paging type 1: The message is transmitted in one LA or RA according to LAI or RAI. After calculating the paging time, the paging message will be transmitted at that time If UE is in CELL_PCH or URA_PCH state, the UTRAN transmits the paging

information in PAGING TYPE 1 message to UE. After received paging message, UE performs a cell update procedure to transit state to CELL_FACH.

z As shown in the above figure, the CN initiates paging in a location area (LA), which is covered by two RNCs. After receiving a paging message, the RNC searches all the cells corresponding to the LAI, and then calculates the paging time, at which it will send the PAGING TYPE 1 message to these cells through the PCCH.

41


Paging Type 2z If UE is in CELL_DCH or CELL_FACH statethe paging

message will be transmitted on DCCH with paging type 2CN SRNC UE

RANAPRANAP

PAGING

RRCRRCDCCH: PAGING TYPE 2

z Paging type 2: If UE is in CELL_DCH or CELL_FACH statethe paging message will be transmitted

on DCCH with paging type 2 The message will be only transmitted in a cell

z As shown in the above figure, if the UE is in the CELL_-DCH or CELL_FACH state, the UTRAN will immediately transmit PAGING TYPE 2 message to the paged UE on DCCH channel.

42


Typical Call Flow of UE UE NAS UE AS NSS MSC

paging

AUTHENTICATION REQUEST

AUTHENTICATION RESPONSE

RR_SECURITY_CONTROL_REQ

(IK CK)

Security mode control

SETUP

CALL CONFIRM

ALERT

CONNECT

CONNECT ACKNOW LEDGE

RAB setup process

paging

RR_EST_REQ (PAGING RESPONSE)

RR_PAING_IND

INITIAL_DIRECT_TRANSFER

(PAGING RESPONSE)

RANAPRANAP

RRC setup process

z Many problems will cause the target UE cannot receive the paging message properly Power setting of paging channel is unreasonable. Unreasonable paging strategies will result in paging channel congestion, which can

cause paging message loss. Paging parameter is unreasonable Equipment fault

43


DRX Procedurez UE receives the paging indicator on PICH periodically, that

is the Discontinuous Reception (DRX)

z The value for the DRX paging cycle length is determined as

follows: :

DRX Cycle Length (2^K)PBP frames

z In idle mode, the UE can monitor the paging in two modes: one is to decode SCCPCH directly every 10ms, the other is to decode the PICH periodically. The second one is the DRX, which is Discontinuous Reception Mechanism.

z The paging period formula: DRX Cycle Length (2^K)*PBP frames K is the CN domain specific DRX cycle length coefficient, which is broadcasted in

SIB1. The typical value is 6. PBP is paging block period, which is 1 for FDD mode The paging period should be 640ms if K is 6

44


DRX Procedure (Cont.)z Through DRX, UE only listens to PICH at certain predefined

time. And UE will read the paging information on SCCPCH if

the paging indicator is 1.

z The value of the Paging Occasion is determined as follows:

Paging Occasion (CELL SFN) =

{(IMSI mod M) mod (DRX cycle length div PBP)} * PBP

+ n * DRX cycle length + Frame Offset

z Paging SFN formula: Paging Occasion (CELL SFN) = {(IMSI mod M) mod (DRX cycle length div PBP)}

*PBP + n *DRX cycle length + Frame Offset n =0, 1, 2and the requirement is the calculated CELL SFN must be below its

maximum value 4096 Frame Offset is 0 for FDD mode M is the number of SCCPCH which carries PCH, and the typical value is 1 The formula cloud be simplified as: SFN = IMSI mod (2^K) + n * (2^K)

45


DRX Procedure (Cont.)

( )( )( ) NpNpSFNSFNSFNSFNPIq mod144144mod512/64/8/18

++++=

z UE must calculate q to know which PI to monitor in one

frame of PICH

z The q value is achieved by the following formula :

z Where, PI = (IMSI div 8192) mod NP

z SFN is the paging occasion of the UEz As shown in the followed figure, the UE needs to monitor the frames (paging occasions)

indicated by the red dots, and then decodes the qth PI of this frame.

0

2^K-1

0 4095

P I P I P I P I

0 1 q NP-1

One DRX cycle

46


DRX Procedure (Cont.)

PICH

Associated S-CCPCH frame

PICH frame containing paging indicator

z Time offset between PICH and S-CCPCH

z The timing relationship between PICH and S-CCPCH is defined by the above figure, and the interval is 3 slots duration (2ms, 7680 chips).

47


Parameters of DRXz DRXCYCLELENCOEF

Parameter name: DRX cycle length coefficient

Recommended value: 6

z PICHMODE

Parameter name: PICH mode

Recommended value: V36.

z DRXCYCLELENCOEF Parameter name: DRX cycle length coefficient Value range: 6~9 . Content: This parameter is broadcasted on SIB1. This parameter is used when a UE is

in idle mode. Recommended value: 6. Set this parameter through ADD CNDOMAIN, query it through LST CNDOMAIN, and

modify it through MOD CNDOMAIN.z PICHMODE

Parameter name: PICH mode Value range: V18, V36, V72, V144 . Physical value range: 18, 36, 72, 144 . Content: Indicating the number of PIs contained in each frame on the PICH. Recommended value: V36 . Set this parameter through ADD PICH, query it through LST PICH.

48


Parameters of DRXz MACCPAGEREPEAT

Parameter name: Number of page re-TX


z MACCPAGEREPEAT Parameter name: Number of page re-TX Number of retransmissions of paging message Value range: 0~2 . Content: If the number of retransmissions of paging message exceeds this parameter

value, retransmissions stop. Recommended value: 1. Set this parameter through SET WFMRCFGDATA, query it through LST

WFMRCFGDATA.

49






5. Paging Procedure

6. Access Procedure

50


Two Working Mode of UEz Idle mode

After turning on, UE will stay in idle mode

z Connected mode

UE will switch to connected mode which could be CELL_FACH

state or CELL_DCH state from the idle mode

After releasing RRC connection, UE will switch to the idle

mode from the connected mode

z The most important difference between idle mode and connected mode is whether UE has RRC connection with UTRAN or not.

z In idle mode, UE will be identified by IMSI, TMSI or PTMSI and so on.z In connected mode, UE will be identified by URNTI (UTRAN Radio Network Temporary

Identity), which is the ID of one RRC connection.

51


Random Access Procedurez Definition

Random access procedure is initiated by UE in order to get

service from the system. Meanwhile, the access channels are

allocated to the UE by system

z This process may happen in the following scenarios: Attach and detach LA update and RA update Signaling connection for services

52


Random Access Channel

AICH accessslots

10 ms

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

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

PRACHaccess slots

SFN mod 2 = 0 SFN mod 2 = 1

10 ms

Access slot set 1 Access slot set 2

z Definition

z UE will transmit the preamble at the access time slotz Each 20ms access frame is composed of two 10ms radio frames, which is divided into 15

access time slot, and 5120 chips for each slotz The PRACH access slots, AICH access slots and their time offset are showed in the above

figure

53


RACH Sub-Channels

1413121110987210765436

14131211109855432107648141312111093

7654321021110981413121

76543210011109876543210

Random access sub-channels numberSFN mod 8

z The access slots of different RACH sub-channels are illustrated by the following table

z A RACH sub-channel defines a sub-set of the total set of uplink access slots. There are a total of 12 RACH sub-channels.

54


Access Service Classz The PRACH resources can be classified into several ASCs,

so as to provide RACH applications with different priorities.

z For Frequency Division Duplex (FDD) mode, the PRACH resources include access timeslots and preamble signatures, which can be classified into several ASCs, so as to provide RACH applications with different priorities.

z The ASCs range from 0 to 7, and the quantity of ASCs is 8. "0" indicates the highest priority and "7" indicates the lowest priority.

z The system will assign random access sub-channels and signatures according to the ASC (Access Service Class ) of UE.

z Set ASC of PRACH through ADD PRACHASC, modify it through MOD PRACHASC, and remove it through RMV PRACHASC.

55


Access Control z Access Control is used by network operators to prevent

overload of radio access channels under critical conditions.

Access class 0~Access Class 9

Access class 11~Access Class 15

Access class 10

z The access class number is stored in the SIM/USIM.z Access class 0~9 are allocated to all the users. And the 10 classes show the same priority.z Access class 11~15 are allocated to specific high priority users as follows. (The enumeration is

not meant as a priority sequence): Access class 15: PLMN staff Access class 14: users subscribing to emergency services Access class 13: public organizations Access class 12: users subscribing to security services Access class 11: users responsible for PLMN management

z Access Class 10 indicates whether or not network access for Emergency Calls is allowed for UEs with access classes 0 to 9 or without an IMSI. For UEs with access classes 11 to 15, Emergency Calls are not allowed if both "Access class 10" and the relevant Access Class (11 to 15) are barred. Otherwise, Emergency Calls are allowed.

56


Mapping between AC and ASCz The AC-ASC mapping information is optional and used for

the System Information Block 5 (SIB5) only.

z Set the mapping between AC and ASC through ADD PRACHACTOASCMAP, modify it through MOD PRACHACTOASCMAP, and remove it through RMV PRACHACTOASCMAP.

57

START

Choose a RACH sub channel fromavailable ones

Get available signatures

Set Preamble Retrans Max

Set Preamble_Initial_Power

Send a preamble

Check the corresponding AI

Increase message part power by p-m based on preamble power

Set physical status to be RACHmessage transmitted Set physical status to be Nack

on AICH received

Choose a access slot again

Counter> 0 & Preamblepower-maximum allowed power

z Physical random access procedure 1. Derive the available uplink access slots, in the next full access slot set, for the set of

available RACH sub-channels within the given ASC. Randomly select one access slot among the ones previously determined. If there is no access slot available in the selected set, randomly select one uplink access slot corresponding to the set of available RACH sub-channels within the given ASC from the next access slot set. Therandom function shall be such that each of the allowed selections is chosen with equal probability

2. Randomly select a signature from the set of available signatures within the given ASC

3. Set the Preamble Retransmission Counter to Preamble_ Retrans_ Max 4. Set the parameter Commanded Preamble Power to Preamble_Initial_Power 5. Transmit a preamble using the selected uplink access slot, signature, and preamble

transmission power 6. If no positive or negative acquisition indicator (AI +1 nor 1) corresponding to the

selected signature is detected in the downlink access slot corresponding to the selected uplink access slot:

A: Select the next available access slot in the set of available RACH sub-channels within the given ASC

B: select a signature C: Increase the Commanded Preamble Power D: Decrease the Preamble Retransmission Counter by one. If the Preamble

Retransmission Counter > 0 then repeat from step 6. Otherwise exit the physical random access procedure

7. If a negative acquisition indicator corresponding to the selected signature is detected in the downlink access slot corresponding to the selected uplink access slot, exit the physical random access procedure Signature

8. If a positive acquisition indicator corresponding to the selected signature is detected , Transmit the random access message three or four uplink access slots after the uplink access slot of the last transmitted preamble

9. Exit the physical random access procedure

59


RRC Connection Message

z Typical RRC connection messages RRC_CONNECTION_REQUEST

RRC_CONNECTION_SETUP

RRC_CONNECTION_SETUP_COMPLETE

RRC_CONNECTION_RELEASE

z When a UE needs network service, it first sets up RRC connection as follows: The UE sends a RRC CONNECTION REQUEST message from the cell where it

camps to the RNC. The RNC allocates related resources for the UE and sends an RRC CONNECTION

SETUP message to the UE. The UE sends a RRC CONNECTION SETUP COMPLETE message to the RNC. The

RRC connection setup ends.

60


UE Timers and Constants in Idle Mode

z T300

Parameter name: Timer 300 [ms]

Recommended value: D2000, namely 2000ms

z N300

Parameter name: Constant 300


z T300 Parameter name: Timer 300[ms] Value range: D100, D200, D400, D600, D800, D1000, D1200, D1400, D1600, D1800,

D2000, D3000, D4000, D6000, D8000 . Physical value range: 100, 200, 400, 600, 800, 1000, 1200, 1400, 1600, 1800, 2000,

3000, 4000, 6000, 8000 Physical unit: ms Content: T300 is started after the UE transmits the RRC CONNECTION REQUEST

message and stopped after the UE receives the RRC CONNECTION SETUP message. RRC CONNECTION REQUEST resents upon the expiry of the timer if V300 less than or equal to N300. Otherwise, the UE enters idle mode.

Recommended value: D2000. Set this parameter through SET IDLEMODETIMER, query it through SET

IDLEMODETIMER.z N300

Parameter name: Constant 300 Value range: 0~7 . Content: Maximum number of retransmission of RRC CONNECTION REQUEST . Recommended value: 3. Set this parameter through SET IDLEMODETIMER, query it through SET

IDLEMODETIMER.

61


UE Timers and Constants in Idle Mode

z T312

Parameter name: Timer 312 [s]

Recommended value: 6, namely 6s

z N312

Parameter name: Constant 312

Recommended value: D1, namely 1

z T312 Parameter name: Timer 312[s] Value range: 1~15 . Physical value range: 1~15s Physical unit: s Content: T312 is started after the UE starts to establish a DCH and stopped when the

UE detects N312 consecutive "in sync" indications from L1. It indicates physical channel setup failure upon the expiry of the timer.

Recommended value: 6. Set this parameter through SET IDLEMODETIMER, query it through SET

IDLEMODETIMER.z N312

Parameter name: Constant 312 Value range: D1, D2, D4, D10, D20, D50, D100, D200, D400, D600, D800, D1000 . Physical value range: 1, 2, 4, 10, 20, 50, 100, 200, 400, 600, 800, 1000 Content: Maximum number of consecutive "in sync" indications received from L1. . Recommended value: D1. Set this parameter through SET IDLEMODETIMER, query it through SET

IDLEMODETIMER.

62


RRC Connection Establish Channel Type and Bit Ratez RRCCAUSE

Parameter name: Cause of RRC connection establishment

Recommended value: none

z SIGCHTYPE

Parameter name: Channel type for RRC establishment

Recommended value: none

z RRCCAUSE Parameter name: Cause of RRC connection establishment Value range: ORIGCONVCALLEST, ORIGSTREAMCALLEST, ORIGINTERCALLEST,

ORIGBKGCALLEST, ORIGSUBSTRAFFCALLEST, TERMCONVCALLEST, TERMSTREAMCALLEST, TERMINTERCALLEST, TERMBKGCALLEST, EMERGCALLEST, INTERRATCELLRESELEST, INTERRATCELLCHGORDEREST, REGISTEST, DETACHEST, ORIGHIGHPRIORSIGEST, ORIGLOWPRIORSIGEST, CALLREEST, TERMHIGHPRIORSIGEST, TERMLOWPRIORSIGEST, TERMCAUSEUNKNOWN, DEFAULTEST.

Content: The cause of Rrc connection establishment. . Recommended value: none. Set this parameter through SET RRCESTCAUSE, query it through LST

RRCESTCAUSE.z SIGCHTYPE

Parameter name: Channel type for RRC establishment Value range: FACH, DCH_3.4K_SIGNALLING, DCH_13.6K_SIGNALLING. Content: FACH indicates that the RRC is established on the common channel.

DCH_3.4K_SIGNALLING indicates that the RRC is established on the dedicated channel of 3.4 kbit/s. DCH_13.6K_SIGNALLING indicates that the RRC is established on the dedicated channel of 13.6 kbit/s. .

Recommended value: none. Set this parameter through SET RRCESTCAUSE, query it through LST

RRCESTCAUSE.

63


RRC Connection Establish Channel Type and Bit Ratez INTRAMEASCTRL

Parameter name: IntraMeas Ctrl Ind for RRC establishment

Recommended value: SUPPORT

z INTRAMEASCTRL Parameter name: IntraMeas Ctrl Ind for RRC establishment Value range: NOT_SUPPORT, SUPPORT. Content: NOT_SUPPORT indicates that the Intrafreq measurement control message

will be send in RRC Connection Establishment. SUPPORT indicates that the Intrafreqmeasurement control will not be send in RRC Connection Establishment.

Recommended value: SUPPORT . Set this parameter through SET RRCESTCAUSE, query it through LST

RRCESTCAUSE.

64

Thank youwww.huawei.com

65

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WCDMA Power Control and Relevant Parameters

263


Objectives

z Upon completion of this course, you will be able to:

Describe the purpose and function of power control

Explain open loop power control and parameters

Explain inner loop power control and relevant parameters

Explain outer loop power control and relevant parameters

264


Contents

1. Power Control Overview

2. Open Loop Power Control

3. Closed Loop Power Control

265


Contents




266


Purpose of Uplink Power Control

z Uplink Transmission Character Self-interference system

Uplink capacity is limited by interference level

Near-far effect

Fading

z Uplink Power Control Function Ensure uplink quality with minimum transmission power

Decrease interference to other UE, and increase capacity

Solve the near-far effect

Save UE transmission power

z CDMA system have the embedded characteristics of self-interference, for uplink one users transmission power become interference to others.

z The more connected users, the higher interference. Generally the capacity is limited by interference level.

z WCDMA suffer from Near-far effect, which means if all UE use the same transmission power, the one close to the NodeB may block the entire cell.

z Uplink power control can guarantee the service quality and minimize the required transmission power. It will resolve the near-far effect and resist fading of signal propagation. By lowering the uplink interference level, the system capacity will be increased.

267


Purpose of Downlink Power Control

z Downlink Transmission Character Interference among different subscribers

Interference from other adjacent cells

Downlink capacity is limited by NodeB transmission power

Fading

z Downlink Power Control Function Ensure downlink quality with minimum transmission power

Decrease interference to other cells, and increase capacity

Save NodeB transmission power

z The downlink has different characteristics from the uplink, for downlink interference is caused by multi-path, part of one users power also become interference to others.

z Downlink power from adjacent cells also is one part of interference to the own cell.

z Transmission power of NodeB is shared by all users channels, so downlink capacity usually is considered to be limited by transmission power.

z Downlink power control also can guarantee the service quality and minimize the required transmission power, so the capacity is maximized in case that interference is lowered.

268


Effect of Power Control

Time (ms)0 200 400 600 800

-20

-15

-10

-5

0

5

10

15

20

Rel

ativ

e po

wer

(dB

)

Channel FadingTransmitting powerReceiving power

z Because of channel fading in mobile communication system, the radio signal is deteriorated and fluctuated, the fast power control become one key technology to resist this phenomenon.

z In this figure, the channel fading is compensated by the transmitting power, which is adjusted by the fast power control, so the receiving power is almost constant and the radio propagation condition is improved.

269


Power Control Classification

z Open Loop Power Control

Uplink / Downlink Open Loop Power Control

z Closed Loop Power Control

Uplink / Downlink Inner Loop Power Control

Uplink / Downlink Outer Loop Power Control

z In WCDMA system, power control includes open loop and closed loop power control.

z Open loop power control is used to determine the initial transmission power, and the closed loop power control adjusts the transmission power dynamically and continuously during the connection.

z For uplink, the UEs transmission power is adjusted; and for downlink, the NodeBs transmission power is adjusted.

270


Power Control For Physical Channels

z Power control methods are adopted for these physical channels:

" can be applied, " not applied

SCH

PICHAICHPRACHSCCPCHPCCPCH

DPCCHDPDCH

Outer Loop Power Control

Inner Loop Power Control

No Power Control

Closed Loop Power ControlOpen Loop Power Control

Physical Channel

z Open loop power control is used in two cases:

1. to decide the initial transmission power of PRACH preamble.

2. to decide the initial transmission power of DPCCH / DPDCH.

z Closed loop power control is only applied on DPCCH and DPDCH

z For other common channels, power control is not applied, they will use fixed transmission power:

The PCPICH power is defined by the PCPICH TRANSMIT POWER parameter as an absolute value in dBm.

All other common channels power is defined in relation with the PCPICH TRANSMIT POWER parameter, and measured in dB.

271


Common Physical Channel Power Parameters

z MAXTXPOWER

Parameter name: Max transmit power of cell

The recommended value is 430, namely 43dBm

z PCPICHPOWER

Parameter name: PCPICH transmit power


z MAXTXPOWER

Parameter name: Max transmit power of cell

Value Range: 0 to 500

Physical Value Range: 0dBm to 50 dBm, step 0.1dB


Content: The sum of the maximum transmit power of all DL channels in a cell.

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

z PCPICHPOWER

Parameter name: PCPICH transmit power

Value Range: -100 to 500

Physical Value Range: -10dBm to 50 dBm, step 0.1dB


Content: This parameter should be set based on the actual environment and the downlink coverage should be guaranteed firstly. If PCPICH transmit power is configured too great, the cell capacity will be decreased, for power resources is occupied by common channel and the interference to traffic channels is also increased.

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

272



z PSCHPOWER or SSCHPOWER

Parameter name: PSCH / SCCH transmit power

The recommended value is -50, namely -5dB

z BCHPOWER

Parameter name: BCH transmit power


z PSCHPOWER or SSCHPOWER

Parameter name: PSCH / SCCH transmit power

Value range: -350 to 150.

Physical value range: -35 to 15, step 0.1dB


Content: The offset between the PSCH / SSCH transmit power and PCPICH transmit power.

For PSCH Power, set it through ADD PSCH, and query it through LST PSCH; for SSCH Power, set it through ADD SSCH, and query it through LST SSCH. And modify it through MOD CELL

z BCHPOWER

Parameter name: BCH transmit power

Value Range-350 to 150

Physical Value Range-35 to 15 dB, step 0.1dB


Content: The offset between the BCH transmit power and PCPICH transmit power.

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

273



z MAXFACHPOWER

Parameter name: Max transmit power of FACH

The recommended value is 10, namely 1dB

z PCHPOWER

Parameter name: PCH transmit power


z MAXFACHPOWER

Parameter name: Max transmit power of FACH

Value range : -350 to 150



Content: The offset between the FACH transmit power and PCPICH transmit power.

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

z PCHPOWER

Parameter name: PCH transmit power

Value Range-350 to 150



Content: The offset between the PCH transmit power and PCPICH transmit power.

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

274



z AICHPOWEROFFSET

Parameter name: AICH power offset

The default value of this parameter is -6, namely -6dB

z PICHPOWEROFFSET

Parameter name: PICH power offset


z AICHPOWEROFFSET

Parameter name: AICH power offset

Value Range -22 to 5

Physical Value Range -22 to 5 dB, step 1dB


Content: The offset between the AICH transmit power and PCPICH transmit power.

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

z PICHPOWEROFFSET

Parameter name: PICH power offset

Value Range-10 to 5

Physical Value Range-10 to 5 dB , step 1dB


Content: The offset between the PICH transmit power and PCPICH transmit power.

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

275


Contents




276


Contents


2.1 Open Loop Power Control Overview

2.2 PRACH Open Loop Power Control

2.3 Downlink Dedicated Channel Open Loop Power Control

2.4 Uplink Dedicated Channel Open Loop Power Control

277


Open Loop Power Control Overview

z Purpose

Calculate the initial transmission power of uplink / downlink channels

z Principle

Estimates the downlink signal power loss on propagation path

Path loss of the uplink channel is related to the downlink channel

z Application

Open loop power control is applied only at the beginning of connection

setup to set the initial power value.

z In downlink open loop power control, the initial transmission power is calculated according to the downlink path loss between NodeB and UE.

z In uplink, since the uplink and downlink frequencies of WCDMA are in the same frequency band, a significant correlation exists between the average path loss of the two links. This make it possible for each UE to calculate the initial transmission power required in the uplink based on the downlink path loss.

z However, there is 90MHz frequency interval between uplink and downlink frequencies, the fading between the uplink and downlink is uncorrelated, so the open loop power control is not absolutely accurate.

278


Contents






279


PRACH Open Loop Power Control

5. Downlink Synchronization

UE Node BServing

RNC

DCH - FP

Allocate RNTISelect L1 and L2parameters

RRCRRC

NBAPNBAP3. Radio Link Setup Response

NBAPNBAP2. Radio Link Setup Request

RRCRRC7. CCCH: RRC Connection Set up

Start RX description

Start TX description

4. ALCAP Iub Data Transport Bearer Setup

RRCRRC9. DCCH: RRC Connection Setup Complete

6. Uplink Synchronization

NBAPNBAP8. Radio Link Restore Indication

DCH - FP

DCH - FP

DCH - FP

Open loop powercontrol of PRACH

1. CCCH: RRC Connection Request

z In access procedure, the first signaling RRC CONNECTION REQUEST is transmitted in message part on PRACH.

z Before PRACH message part transmission, UE will transmit PRACH preamble, and the transmission power of first preamble is calculated by this PRACH open loop power control.

280



z Initial Power Calculation for the First Preamble

When UE needs to set up a RRC connection, the initial power

of uplink PRACH can be calculated according to the following

formula:

Power Tx Initial gCalculatin For Value Constant+ceInterferen UL+CPICH_RSCP-Power Transmit PCPICH=ernitial_PowPreamble_I

z In this formula, where

PCPICH TRANSMIT POWER defines the PCPICH transmit power in a cell. It is broadcast in SIB5.

CPICH_RSCP means received signal code power, the received power measured on the PCPICH. The measurement is performed by the UE.

UL interference is the UL RTWP measured by the NodeB. It is broadcast in SIB7.

CONSTANT VALUE compensates for the RACH processing gain. It is broadcast in SIB5.

z The initial value of PRACH power is set through open loop power control. UE operation steps are as follows:

1. Read Primary CPICH DL TX power, UL interference and Constant valuefrom system information.

2. Measure the value of CPICH_RSCP;

3. Calculate the Preamble_Initial_Power of PRACH.

281


PRACH Open Loop Power Control Parameters

z CONSTANTVALUE

Parameter name: Constant value for calculating initial TX

power


z CONSTANTVALUE

Parameter name: Constant value for calculating initial TX power

Value range : -35 ~ -10

Physical Value Range-35 to -10 dB

Content: It is used to calculate the transmit power of the first preamble in the random access process.

Recommended value: -20

Set this parameter through ADD PRACHBASIC, query it through LST PRACH, and modify it through MOD PRACHUUPARAS

282



z Timing relationship of PRACH and AICH

AICH

PRACH

1 access slot

p-a

p-m p-p

Pre-amble

Pre-amble

Message part

Acq. Ind.

z After UE transmit the first Preamble on PRACH, it will wait for the corresponding AI (Acquisition Indicator) on the AICH. The timing relationship of PRACH and AICH is shown in above figure.

z There will be 3 parameters used to define the timing relationship:

p-p: time interval between two PRACH preambles. p-p is not a fixed value, it is decided by selecting access slot of PRACH preambles,

Here p-p has one restriction, it must be longer than a minimum value p-p min , namely p-p p-p min.

p-a: time interval between PRACH preamble and AICH Acquisition Indicator. If UE sends the PRACH preamble, it will detect the responding AI after p-a time.

p-m: time interval between PRACH preamble and PRACH message part. If UE sends the PRACH preamble and receives positive AI from the AICH, it will send the message part after p-m time.

283



z AICHTXTIMING

Parameter name: AICH transmission timing

Content:

When AICHTXTIMING = 0,

p-p,min = 15360 chips, p-a = 7680 chips, p-m = 15360 chips When AICHTXTIMING = 1,

p-p,min = 20480 chips, p-a = 12800 chips, p-m = 20480 chips The recommended value is 1

z Parameter AICHTXTIMING is used to define the set of p-p min, p-a, p-m.z AICHTXTIMING

Parameter name: AICH transmission timing

Value range0,1

Content:

When AICHTXTIMING = 0,

p-p,min = 15360 chips, p-a = 7680 chips, p-m = 15360 chips When AICHTXTIMING = 1,

p-p,min = 20480 chips, p-a = 12800 chips, p-m = 20480 chips Recommended value: 1

Set this parameter through ADD AICH, query it through LST AICH, and modify it needs de-activated the cell through DEA CELL. After the old configuration of AICH is deleted through RMV AICH , a new AICH can be established through ADD AICH

284



z Power Ramping for Preamble Retransmission

Power Ramp Step

Power Offset Pp-m

Preamble_Initial_Power

Message part

Pre-amblePre-

amble

Pre-amblePre-

amble

1 3 N2

z After UE transmit the first Preamble,

If no positive or negative AI on AICH is received after p-a time, UE shall increase the preamble power by POWER RAMP STEP, and

retransmit the preamble.

This ramping process stops until the number of transmitted preambles has reached the MAX PREAMBLE RETRANSMISSION within an access cycle, or when the maximum number of access cycles has reached MAX PREAMBLE LOOP.

If a negative AI on AICH is received by the UE after p-a time, which indicates rejection of the preamble, the UE shall wait for a certain

Back-off Delay and re-initiate a new random access process.

When a positive AI on AICH is received by UE after p-a time, it will transmit the random access message after the uplink access slot of

the last preamble.

The transmit power of the random access message control part should be POWER OFFSET higher than the power of the last transmitted preamble.

285



z POWERRAMPSTEP

Parameter name: Power increase step


z PREAMBLERETRANSMAX

Parameter name: Max preamble retransmission

The Recommended value is 20

z POWERRAMPSTEP

Parameter name: Power increase step

Value range : 1 to 8

Physical Value Range: 1 to 8 dB

Content: The power increase step of the random access preambles transmitted before the UE receives the acquisition indicator in the random access process.



z PREAMBLERETRANSMAX

Parameter name: Max preamble retransmission


Content: The maximum number of preambles transmitted in a preamble ramping cycle.



286



z MMAX

Parameter name: Max preamble loop

The recommended value is 8

z NB01MIN / NB01MAX

Parameter name: Random back-off lower / upper limit

The recommended value: 0 for both NB01MIN / NB01MAX

z MMAX

Parameter name: Max preamble loop

Value range: 1 to 32

Content: The maximum number of random access preamble loops.


Set this parameter through ADD RACH, query it through LST RACH, and modify it first de-activated the cell through DEA CELL, then MOD RACH.

z NB01MIN / NB01MAX

Parameter name: Random back-off lower / upper limit

Value range: 0 to 50

Content: The lower / upper limit of random access back-off delay.

The recommended value: 0 for both NB01MIN / NB01MAX

Set this parameter through ADD RACH, query it through LST RACH, and modify it first de-activated the cell through DEA CELL, then MOD RACH.

287



z POWEROFFSETPPM

Parameter name: Power offset

The default value:

-3dB for signalling transmission;

-2dB for service transmission.

z POWEROFFSETPPM

Parameter name: Power offset

Value range: -5 to 10dB

Content: The power offset between the last access preamble and the message control part. The power of the message control part can be obtained by adding the offset to the access preamble power.

The recommended value of this parameter is -3dB for signalling transmission , and that -2dB for service transmission

Set this parameter through ADD PRACHTFC, query it through LST PRACH, and modify it de-activated the cell through DEA CELL . After the old configuration of PRACH is deleted through RMV PRACHTFC , a new parameters can be established through ADD PRACHTFC

z The PRACH message also consists of control part and data part, here the POWER OFFSET is the difference between the PRACH preamble and the message control part.

z The PRACH message uses GAIN FACTOR to set the power of control / data part: GAIN FACTOR BETAC ( c ) is the gain factor for the control part. GAIN FACTOR BETAD ( d ) is the gain factor for the data part.

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Contents






289


DL DPDCH Open Loop Power Control

5. Downlink Synchronization

UE Node BServing

RNC

DCH - FP

Allocate RNTISelect L1 and L2parameters

RRCRRC

NBAPNBAP3. Radio Link Setup Response

NBAPNBAP2. Radio Link Setup Request

RRCRRC7. CCCH: RRC Connection Set up

Start RX description

Start TX description

4. ALCAP Iub Data Transport Bearer Setup

RRCRRC9. DCCH: RRC Connection Setup Complete

6. Uplink Synchronization

NBAPNBAP8. Radio Link Restore Indication

DCH - FP

DCH - FP

DCH - FP

1. CCCH: RRC Connection Request


z According to the RRC connection establishment procedure, after RNC received the RRC CONNECTION REQUEST message, and NodeB set up the radio link for UE, then Iub interface resources is established between NodeB and RNC.

z When DCH-FP of Iub interface finished downlink and uplink synchronization, the downlink DPCH starts to transmit, and DPDCH initial transmission power is calculated through open loop power control.

290



z When a dedicated channel is set up, the initial power of

downlink DPDCH can be calculated according to the

following formula:

= Total

CPICH

CPICHDLInitial P)No/Ec(

P)NoEb(

WRP

z In this formula, where

R is the requested data bitrate by the user

W is the chip rate

(Eb/No)DL is the Eb/No target to ensure the service quality. RNC searches for the (Eb/No)DL dynamically in a set of pre-defined values according to specific cell environment type, coding type, bitrate, BLER target and etc.

(Ec/Io)CPICH is the CPICH signal quality measured by UE, then it is sent to RNC through RACH.

is the orthogonality factor in the downlink. In Huawei implementation, is set to 0.

Ptotal is the total carrier transmit power measured at the NodeB

z The initial transmission power of downlink DPDCH could be calculated through this formula, then, initial transmission power of downlink DPCCH can be obtained according to the power offset: PO1, PO2 and PO3.

291



Data1 TPC TFCI Data2 Pilot

DownlinkTransmit

Power

DPCCHDPDCH DPDCH DPCCH

PO2 PO1PO3

1 timeslot

z This figure shows the power offset of downlink DPCH :

PO1 is the power offset of DPCCH TFCI bits to DPDCH data bits.

PO2 is the power offset of DPCCH TPC bits to DPDCH data bits.

PO3 is the power offset of DPCCH Pilot bits to DPDCH data bits.

The values of PO1, PO2 and PO3 are configured on RNC.

292


DL DPDCH Open Loop Power Control Parameter

z TFCIPO

Parameter name: TFCI power offset


z TPCPO

Parameter name: TPC power offset


z TFCIPO

Parameter name: TFCI power offset


Physical value range: 0 to 6 dB, step: 0.25

Content: The offset of TFCI bit transmit power from data bit transmit power in each time slot of radio frames on DL DPCH


Set this parameter through SET FRC, query it through LST FRC, and modify it through SET FRC

z TPCPO

Parameter name: TPC power offset



Content: The offset of TPC bit transmit power from data bit transmit power in each time slot of radio frames on DL DPCH



293


DL DPDCH Open Loop Power Control Parameter

z PILOTPO

Parameter name: Pilot power offset


z PILOTPO

Parameter name: Pilot power offset



Content: The offset of pilot bit transmit power from data bit transmit power in each time slot of radio frames on DL DPCH



294


Downlink Power Control Restriction

z The power of downlink dedicated channel is limited by an

upper and lower limit for each radio link.

The DL DPDCH power could not exceed Maximum_DL_Power,

nor could it be below Minimum_DL_Power.

z RLMAXDLPWR / RLMINDLPWR

Parameter name: RL Max / Min DL TX power

The recommended value is shown in the following table.

z Note: Both downlink open loop and close loop power control will be limited by this parameter.

z RLMAXDLPWR

Parameter name: RL Max DL TX power



Content: The maximum downlink transmit power of radio link. This parameter should fulfill the coverage requirement of the network planning, and the value is relative to [PCPICH transmit power]

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

z RLMINDLPWR

Parameter name: RL Min DL TX power



Content: The minimum downlink transmit power of radio link. This parameter should consider the maximum downlink transmit power and the dynamic range of power control, and the value is relative to [PCPICH transmit power].

Since the dynamic range of power control is set as 15dB, this parameter is recommended as [RL Max DL TX power] 15 dB.

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

295


Downlink Power Restriction Parameters

z Referential configurations for typical services:

8-114384 kbps

8-132256 kbps

16-150144 kbps

32-17-264 kbps

64-19-432 kbps

128-23-88 kbps

PS Domain

32-15064 kbps

32-15056 kbps

64-17-232 kbps

64-17-228 kbps

128-18-312.2 kbps AMR

CS Domain

Downlink SFRL Min Downlink Transmit PowerRL Max Downlink Transmit PowerService

296


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297


UL DPCCH Open Loop Power Control

5. Downlink Synchroni

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