wcdma powercontrol 120618044133 phpapp02

Huawei Technologies Proprietary

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Table of Contents

Chapter 1 Power Control .............................................................................................................. 1-1 1.1 Summary of Updates ......................................................................................................... 1-1 1.2 Introduction ........................................................................................................................ 1-1

1.2.1 Definition ................................................................................................................. 1-1 1.2.2 Purpose ................................................................................................................... 1-2 1.2.3 Terms and Abbreviations ........................................................................................ 1-2

1.3 Availability .......................................................................................................................... 1-3 1.3.1 Involved Network Element ...................................................................................... 1-3 1.3.2 Software Release .................................................................................................... 1-4 1.3.3 Miscellaneous.......................................................................................................... 1-4

1.4 Impact ................................................................................................................................ 1-4 1.4.1 On System Performance ......................................................................................... 1-4 1.4.2 On Other Features .................................................................................................. 1-4

1.5 Restrictions ........................................................................................................................ 1-4 1.6 Technical Description ........................................................................................................ 1-5

1.6.1 Power Control Configuration Model ........................................................................ 1-5 1.6.2 Open-Loop Power Control ...................................................................................... 1-8 1.6.3 Inner-Loop Power Control ..................................................................................... 1-38 1.6.4 Outer-Loop Power Control .................................................................................... 1-48 1.6.5 Downlink Power Balance ...................................................................................... 1-57

1.7 Capabilities ...................................................................................................................... 1-61 1.8 Implementation ................................................................................................................ 1-61

1.8.1 Enabling Power Control ........................................................................................ 1-61 1.8.2 Reconfiguring Power Control Parameters ............................................................ 1-61 1.8.3 Disabling Power Control ........................................................................................ 1-63

1.9 Maintenance Information ................................................................................................. 1-63 1.9.1 Alarms ................................................................................................................... 1-63 1.9.2 Counters ................................................................................................................ 1-63

1.10 References ..................................................................................................................... 1-63


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List of Figures

Figure 1-1 Power control configuration model (1) .................................................................. 1-5 Figure 1-2 Power control configuration model (2) .................................................................. 1-6 Figure 1-3 Power control configuration model (3) .................................................................. 1-6 Figure 1-4 Power control configuration model (4) .................................................................. 1-6 Figure 1-5 Power control configuration model (5) .................................................................. 1-6 Figure 1-6 Power control configuration model (6) .................................................................. 1-7 Figure 1-7 Power control configuration model (7) .................................................................. 1-7 Figure 1-8 Power control configuration model (8) .................................................................. 1-8 Figure 1-9 PRACH preamble and message parts ................................................................. 1-9

Figure 1-10 Uplink open-loop power control on PRACH ....................................................... 1-9

Figure 1-11 Downlink open-loop power control on the DPDCH .......................................... 1-34

Figure 1-12 Uplink inner-loop power control ........................................................................ 1-39

Figure 1-13 Downlink inner-loop power control ................................................................... 1-44

Figure 1-14 Uplink outer-loop power control procedure ...................................................... 1-49

Figure 1-15 Downlink power balance................................................................................... 1-57


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List of Tables

Table 1-1 NEs required for power control ............................................................................... 1-4

Table 1-2 Product versions ..................................................................................................... 1-4

Table 1-3 Outer-loop Power Control Parameters on RAB basis .......................................... 1-55

Table 1-4 Commands for the reconfiguration on the RNC side ........................................... 1-62


1-1

Chapter 1 Power Control

1.1 Summary of Updates This section provides the update history of this manual and introduces the contents of subsequent updates.

Manual Version Description

01 (2006-9-26) Modified the principles to adjust SIR target in case of multi-service.

02 (2006-9-28) Add description to the Rate Matching.

1.2 Introduction

The WCDMA system is a self-interfered system. The most important way to restrain system interference level is the power control, especially in the uplink direction. Without power control, a single overpowered UE could block a whole cell.

1.2.1 Definition

The power control is performed by the UE or UTRAN to adjust and control the power of transmit signals according to the changes of channel environment and the quality of receive signals.

In the WCDMA system, the power control mechanism comprises the following parts:

Open-loop power control: Applicable in UL and DL. It sets the initial uplink and downlink transmit power. Open-loop power control is used on physical channels such as PRACH, DPCH.

Inner-loop power control: Applicable in UL and DL. It directly adjusts the uplink and downlink transmit power using power control commands. The inner loop power control is performed by each UE and NodeB with the frequency of 1500 times per second (1.5 kHz).

Outer-loop power control: Applicable in UL and DL. It indirectly controls the uplink and downlink transmit power by increasing or decreasing the target SIR value.

DL power balance: It is used to reduce the downlink power drifting of a given UE during soft handover.


1-2

1.2.2 Purpose

The purpose of power control is to adjust the uplink and downlink power to the minimum while ensuring the QoS. In the uplink, if a UE near the NodeB has too large a transmit power, it may cause

great interference to other UEs on the edge of the cell or even block the whole cell. This is called near-far effect. In that case, uplink power control is needed.

In the downlink, the system capacity is determined by the total required code power for each connection. Therefore, it is necessary to keep the transmit power at the lowest level while ensuring signal quality at the receiving end for each UE. In that case, the downlink power control is needed.

Power control can be used against shadow fading and fast fading. Power control can increase system capacity. Power control for power drifting can improve the soft handover performance in the

downlink.

1.2.3 Terms and Abbreviations

I. Terms

None.

II. Abbreviations

Abbreviation Full Spelling

3GPP 3rd Generation Partnership Project AMR Adaptive MultiRate

BER Bit Error Rate

BLER Block Error Rate

CDMA Code Division Multiple Access

CPCH Common Packet Channel

CPICH Common Pilot Channel

DCH Dedicated Channel

DL Downlink

DPB Downlink Power Balance

DPCCH Dedicated Physical Control Channel

DPCH Dedicated Physical Channel

DPDCH Dedicated Physical Data Channel

FDD Frequency Division Duplex


1-3

Abbreviation Full Spelling

FER Frame Error Rate

LMT Local Maintenance Terminal

MML Man-Machine Language

MRC Maximum Ratio Combining

OLPC Outer-Loop Power Control

PCA Power Control Algorithm

P-CPICH Primary Common Pilot Channel

PRACH Physical Random Access Channel

RAN Radio Access Network

RNC Radio Network Controller

RRC Radio Resource Control

RSCP Received Signal Code Power

RTWP Received Total Wideband Power

SHO Soft Handover

SIR Signal-Interference Ratio

SRNC Serving RNC

TFCI Transport Format Combination Indicator

TPC Transmit Power Control

UE User Equipment

UL Uplink

UMTS Universal Mobile Telecommunications System

UTRAN UMTS Terrestrial Radio Access Network

Uu Uu Interface

WCDMA Wideband CDMA

1.3 Availability 1.3.1 Involved Network Element

Table 1-1 shows the Network Elements (NEs) required for power control.


1-4

Table 1-1 NEs required for power control

UE NodeB RNC MSC Server MGW SGSN GGSN HLR

- - - - -

Note: - = NE not required = NE required

1.3.2 Software Release

Table 1-2 describes the versions of the HUAWEI UMTS RAN products that support power control.

Table 1-2 Product versions

Product Version

RNC BSC6800 V100R002 and later releases

NodeB

DBS3800 V100R006 and later releases

BTS3812A V100R002 and later releases

BTS3812E V100R002 and later releases

1.3.3 Miscellaneous

None.

1.4 Impact 1.4.1 On System Performance

Power control improves the system capacity and ensures the QoS.

1.4.2 On Other Features

None.

1.5 Restrictions None.


1-5

1.6 Technical Description Power control in the uplink and the downlink is different. UL power control and DL power control are separately described.

1.6.1 Power Control Configuration Model

The configuration model for power control is as show in Figure 1-1, Figure 1-2, Figure 1-3, Figure 1-4, Figure 1-5, Figure 1-6, Figure 1-7 and Figure 1-8.

RNC

RadioClass

GlobalParaClass CellClass

TYPRABBASIC.Class

TYPSRBBASIC.Class

CELL.Class

RAB&SRBClass

PCPICH.Class

PRACHBASIC.Class

PRACHUUPARAS.Class

AICH.Class

RACH.Class

PRACHTFC.Class

CELLCAC.ClassTYPSRB.Class

TYPRAB.Class

CELLSETUP.Class

PSCH.Class

SSCH.Class

BCH.Class

FACH.Class

SCCPCH.Class

CHPWROFFSET.Class

AICHPWROFFSET.Class

PICHPWROFFSET.Class

CELLRLPWR.ClassTYPSRBOLPC.Class

TYPRABOLPC.Class

OLPC.Class

CELLOLPC.Class

DPB.Class

FRC.Class

CORRMALGOSWITCH.Class

TYPSRBSEMISTATICTF.Class

TYPRABSEMISTATICTF.Class

Figure 1-1 Power control configuration model (1)


1-6

TFCI power offset

TPC power offset

Pilot power offset

Power control algorithm selection

UL closed loop power control step size

DL power control mode

FRC.Class

FDD DL power control step size

Constant value configured by default

Max UL TX power of conversational service

Max UL TX power of streaming service

Max UL TX power of interactive service

Max UL TX power of background service

RRC Proc DPDCH PC preamble length

RRC Proc SRB delay

HHO Proc DPDCH PC preamble length

HHO Proc SRB delay

Initial power offset for SHO

CELLCAC.Class


Max preamble loop

Random back-off lower limit

Random back-off upper limit

RACH.Clsass

RL Max DL TX power

RL Min DL TX power

CELLRLPWR.Class


Power increase limit

DL power window average size

DL power control mode 1

CELLSETUP.Clsass

Power offset

ADD PRACHTFC

Gain Factor BetaD

PRACHTFC.Class


AICH power offset

PICH power offset

AICHPWROFFSET.Class

CHPWROFFSET.Class

PICHPWROFFSET

Power increase step

Max preamble retransmission

PRACHUUPARAS.Class

PRACHBASIC.Class

Constant value for calculating initial TX power



1-7

DPB.Class

DPB measurement report period

DPB measurement filter coefficient

DPB triggering threshold

DPB stop threshold

Ratio for max power

DPB adjustment ratio

DPB adjustment period

Max DPB adjustment step

BLER target value

SIR adjustment step

Maximum SIR increase step

Maximum SIR decrease step

Maximum SIR target

Minimum SIR target

TYPSRBOLPC.Class

TYPRABOLPC.Class


UL rate matching attribute DL rate matching attribute

TYPRABSEMISTATICTF.Class TYPSRBSEMISTATICTF.Class

AICH.Class

Reference BetaC

Reference BetaD

AICH transmission timing

PCPICH transmit power

PSCH transmit power

BCH transmit power

CELL.Class

PCPICH.Class

PSCH.Class

BCH.Class

TYPSRBBASIC.Class

TYPSRB.Class

TYPRABBASIC.Class

TYPRAB.Class



1-8

SIR init target value

TYPSRBOLPC.Class

OLPC adjustment period

PCH power

Max transmit power of FACH

SCCPCH.Class

FACH.Class

PCH.Class

SIR measurement filter coefficient

SIR adjustment coefficient

CELLOLPC.Class

OLPC.Class

SSCH transmit power

SSCH CELL.Class

Max allowed UE UL TX power

CELLSELRESEL.Class

Power control algorithm switch

CORRMALGOSWITCH.Class


1.6.2 Open-Loop Power Control

Based on the measurement acquirement of receive power, open-loop power control attempts to make a rough estimation of path loss by means of a downlink signal, and then to provide a coarse initial power setting of the UE and the NodeB at the beginning of a connection.

I. Uplink Open-Loop Power Control

1) Uplink Open-Loop Power Control on PRACH The PRACH random access process is comprised of two different parts that the UE will send to the system: preamble part and message part.


1-9

One access slot

p-a

p-mp-p

Pre-amble

Pre-amble Message part

Acq.Ind.

PRACH accessslots TX at UE

AICH accessslots RX at UE

Figure 1-9 PRACH preamble and message parts

The preamble part is at the length of 4096 chips and consists of 256 repetitions of a signature that is 16chip long. There are a maximum of 16 signatures available.

The message part is 10 or 20 ms long and is comprised of a control part and a data part. The data and control parts are transmitted in parallel. Once the UE receives an answer on the corresponding AICH, it will send the message part of the PRACH.

Therefore, the parameters related to the UE access on the PRACH involve three parts:

Initial power calculation for the first preamble Power ramping for preamble retransmission Power setting for message part

Initial Power Calculation for the First Preamble To determine the initial power of the UE on its first PRACH preamble transmission, both UE and UTRAN are involved, as shown in Figure 1-10.

BCH :CPICH channel power UL interference level

Measure CPICH_RSCPDetermine the initial transmitted power

RACH

Figure 1-10 Uplink open-loop power control on PRACH


1-10

Prior to PRACH transmission, the UE shall acquire the System Information Block (SIB) that includes "Primary CPICH Tx power", UL interference, and Constant value. The UE measures the value for the CPICH_RSCP and calculates the initial power for the first PRACH preamble with the following formula:

Preamble_Initial_Power (PRACH) = PCPICH TRANSMIT POWER - CPICH_RSCP + UL interference + CONSTANT VALUE FOR CALCULATING INITIAL TX POWER

Where:

The PCPICH TRANSMIT POWER parameter defines the PCPICH transmit power in a cell. It is broadcast in SIB 5.

Parameter name PCPICH transmit power

Parameter ID PCPICHPOWER

GUI range -100500 Physical range& unit -1050, step: 0.1 (dBm) Default value 330

Optional / Mandatory Optional

MML command ADD PCPICH/ MOD CELL

Description: This parameter should be set based on the actual system environment such as cell coverage (radius) and geographical environment. For the cells to be covered, the downlink coverage should be guaranteed as a premise. For the cells requiring soft handover area, this parameter should satisfy the proportion of soft handover areas stipulated in the network planning. If the maximum transmit power of the PCPICH is configured too great, the cell capacity will be decreased because a lot of system resources will be occupied and the interference with the downlink traffic channels will be increased.

Recommendation:

PCPICH TRANSMIT POWER is related to the downlink coverage in the network planning. The default setting is 330, namely 33 dBm. If this parameter is too small, it will influence directly the downlink pilot coverage range; if it is too big, the downlink interference will increase, and the transmit power that can be distributed to the services will be reduced, which will affect the downlink capacity. Meanwhile, the configuration of this parameter also has influence on the distribution of handover areas.

CPICH_RSCP is the received signal code power, the received power on one code measured on the primary CPICH. It is measured by the UE.

UL interference is the UL RTWP measured by the NodeB, including noise generated in the receiver, within the bandwidth defined by the receiver pulse shaping filter. It is broadcast in SIB 7.


1-11

The CONSTANT VALUE FOR CALCULATING INITIAL TX POWER parameter compensates for the RACH processing gain. It is broadcast in SIB 5.

Parameter name Constant value for calculating initial TX power

Parameter ID CONSTANTVALUE

GUI range -35-10. Physical range& unit dB

Default value -20


MML command ADD PRACHBASIC/MOD PRACHUUPARAS

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

Power Ramping for Preamble Retransmission If no positive or negative acquisition indicator on AICH is received by the UE from the network after a given period, then the UE shall increase the preamble power by POWER INCREASE STEP so that the Node-B can detect it, and re-send the preamble. This ramping up process is characterized below:

AICH transmission timing: In order to avoid too many collisions and consider the processing capability of NodeB, it is specified in 3GPP that a UE shall wait at least 3 or 4 access slots between the transmissions of 2 consecutive preambles, according to the parameter AICH TRANSMISSION TIMING.

Power increment step: Each time the UE re-transmits a preamble, the transmit power is increased by POWER INCREASE STEP, compared to the previous transmitted preamble.

Maximum number of transmitted preambles: This limitation is defined by MAX PREAMBLE RETRANSMISSION and MAX PREAMBLE LOOP parameters. MAX PREAMBLE RETRANSMISSION defines the maximum number of transmitted preambles allowed within an access cycle, and MAX PREAMBLE LOOP defines the maximum number of random access preamble cycles. An access cycle is defined by a number of radio frames on which the PRACH access (and therefore a preamble ramping cycle) is allowed on specific slot numbers.


1-12

Parameter name AICH transmission timing

Parameter ID AICHTXTIMING

GUI range 01 Physical range& unit None

Default value 1


MML command ADD AICH

Description: The transmission timing information of an AICH. "0" indicates that there are 7680 chips offset between the access preamble of the PRACH and AICH; "1" indicates that there are 12800 chips offset between them.

Caution:

In order to change the value of the AICH TRANSMISSION TIMING parameter, the cell shall be firstly de-activated through DEA CELL. After the old configuration of AICH is deleted through RMV AICH, a new AICH can be established through ADD AICH.

Parameter name Power increase step

Parameter ID POWERRAMPSTEP

GUI range 18 Physical range& unit dB

Default value 2



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

Recommendation:

If the value of POWER INCREASE STEP is too big, the access process will be shortened, but the probability of wasting power will be bigger; if it is too small, the access process will be lengthened, but transmitting power will be saved. It is a value to be weighed.


1-13

Parameter name Max preamble retransmission

Parameter ID PREAMBLERETRANSMAX

GUI range 164

Physical range& unit None

Default value 20



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

Recommendation:

The product of the MAX PREAMBLE RETRANSMISSION parameter and the above-mentioned PRACH POWER INCREASE STEP determines the maximum ramp power of the UE within a preamble ramp cycle. If this value is too small, the preamble power may fail to ramp to the required value, resulting in UE access failure; if it is too big, the UE may repeatedly increase the power and make access attempts, resulting in interference to other users.

Parameter name Max preamble loop

Parameter ID MMAX

GUI range 132


Default value 8


MML command ADD RACH/MOD RACH

Description: The maximum number of random access preamble loops.

Caution:

In order to change the value of the MAX PREAMBLE LOOP parameter, if the current cell is on-going and there is one and only one PRACH in this cell, the cell shall be firstly de-activated through DEA CELL.


1-14

The 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 MAX PREAMBLE LOOP is reached.

When a negative acquisition indicator on AICH is received by the UE, which indicates rejection of the preamble, the UE shall wait for a certain back-off delay and re-initiate a new random access process. Two parameters RANDOM BACK-OFF LOWER LIMIT and RANDOM BACK-OFF UPPER LIMIT are defined respectively as the lower and upper bounds of the random access back-off delay.

Parameter name Random back-off lower limit

Parameter ID NB01MIN

GUI range 050


Default value 0



Description: The lower limit of random access back-off delay.

Parameter name Random back-off upper limit

Parameter ID NB01MAX

GUI range 050


Default value 0



Description: The upper limit of random access back-off delay.

Configuration Rule and Restriction: RANDOM BACK-OFF LOWER LIMIT shall not be set bigger than RANDOM BACK-OFF UPPER LIMIT. If RANDOM BACK-OFF LOWER LIMIT = RANDOM BACK-OFF UPPER LIMIT, it means that the retransmission periodicity of preamble part is fixed.


1-15

Caution:

In order to change the value of the RANDOM BACK-OFF LOWER LIMIT or RANDOM BACK-OFF UPPER LIMIT parameter, if the current cell is on-going and there is one and only one PRACH in this cell, the cell shall be firstly de-activated through DEA CELL.

Power Setting for Message Part When the UE has received a positive acquisition indicator on AICH, it will transmit the random access message using three or four uplink access slots after the uplink access slot of the last transmitted preamble, depending on the AICH transmission timing parameter. This message is made up of a control part and a data part:

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

Parameter name Power offset

Parameter ID POWEROFFSETPPM

GUI range -510

Physical range& unit dB

Default value Values according to PRACH TFC

Optional / Mandatory Mandatory

MML command ADD PRACHTFC

Description: 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.

Configuration Rule and Restriction: POWER OFFSET must be set for each instance of PRACH TFC.

Recommendation:


1-16

It is recommended that the value of POWER OFFSET corresponding to the TFC for signaling transmission is set to -3 dB, and that corresponding to the TFC for service transmission is set to -2 dB. If the value of POWER OFFSET is set too low, it is likely that the signaling or the service data carried over the RACH can not be correctly received, which affects the uplink coverage. If the value is set too high, the uplink interference is increased, and the uplink capacity is affected.

Caution:

In order to change the value of the POWER OFFSET parameter, if the current cell is on-going and there is one and only one PRACH in this cell, the cell shall be firstly de-activated through DEA CELL.

Data part: The message part of the uplink PRACH channel employs gain factors to control the control/data part:

a) GAIN FACTOR BETAC (c) is the gain factor for the control part. b) GAIN FACTOR BETAD (d) is the gain factor for the data part.

Parameter name Gain Factor BetaC

Parameter ID GAINFACTORBETAC

GUI range 115


Default value None



Description: The power occupancy factor of the control part.


1-17

Parameter name Gain Factor BetaD

Parameter ID GAINFACTORBETAD

GUI range 115


Default value None



Description: The power occupancy factor of the data part.

PRACH CTFC POWER OFFSET GAIN FACTOR BETAC GAIN FACTOR

BETAD

0 -3 13 15

1 -2 10 15

Configuration Rule and Restriction: Either Gain Factor BetaC or Gain Factor BetaD must be set to 15 for each instance of power difference between control and data part of PRACH.

Caution:

In order to change the value of the GAIN FACTOR BETAC or GAIN FACTOR BETAD parameter, if the current cell is on-going and there is one and only one PRACH in this cell, the cell shall be firstly de-activated through DEA CELL.

2) Uplink Open-Loop Power Control on DPCCH The UL open-loop power control on dedicated channel aims to determine the initial power of the first uplink DPCCH.

When setting up the first DPCCH, the UE shall start the UL inner loop power control at a power level and set the initial power of uplink DPCCH with the following formula:

DPCCH_Initial_Power = DPCCH_Power_Offset - CPICH_RSCP

Where:

CPICH_RSCP is the received signal code power, the received power on one code measured on the primary CPICH. It is a measurement performed by the UE.


1-18

DPCCH_Power_Offset is provided by the RNC to the UE via RRC signaling in the Uplink power control info IE or in the Uplink power control info short IE. These IEs are included in the RRC messages of the radio bearer setup, reconfiguration and release, transport channel and physical channel reconfiguration, RRC connection setup and re-establishment and in the handover to UTRAN command. For Huawei, DPCCH_Power_Offset is calculated with the following formula:

DPCCH_Power_Offset = PCPICH TRANSMIT POWER + UL interference + CONSTANT VALUE CONFIGURED BY DEFAULT

Where: The PCPICH TRANSMIT POWER parameter defines the PCPICH transmit power

in a cell. UL interference is the UL RTWP measured by the NodeB. The CONSTANT VALUE CONFIGURED BY DEFAULT parameter reflects the

target Ec/No of the uplink DPCCH preamble. Parameter name Constant value configured by default

Parameter ID DEFAULTCONSTANTVALUE

GUI range -35-10

Physical range& unit dB

Default value -27


MML command SET FRC

Description: This parameter is used by the RNC to compute the DPCCH power offset which is used by the UE to calculate the initial transmit power of UL DPCCH during the open loop power control process.

Maximum Allowed UL Transmit Power The maximum allowed UL transmit power defines the total maximum output power allowed for the UE and depends on the desired type of service. The information will be transmitted on the FACH, mapped on the S-CCPCH, to the UE in the RADIO BEARER SETUP message of the RRC protocol during the call setup.

For Huawei, the MAX ALLOWED UE UL TX POWER parameter is the maximum transmit power of the PRACH channel when the UE tries to access to the specified cell.


1-19

Parameter name Max allowed UE UL TX power

Parameter ID MAXALLOWEDULTXPOWER

GUI range -5033

Physical range& unit dBm

Default value 24


MML command ADD CELLSELRESEL; MOD CELLSELRESEL

Description: The maximum allowed uplink power transmitted on RACH of a UE in the cell, which is related to the network planning.

Configuration Rule and Restriction: If the value of MAX ALLOWED UE UL TX POWER is higher than the UE capability, the maximum transmission power is of course limited by the UE capability. The transmission power on the PRACH for preamble part and message part cannot be higher than the MAX ALLOWED UE UL TX POWER parameter.

In addition, there are four parameters (MAX UL TX POWER OF CONVERSATIONAL SERVICE, MAX UL TX POWER OF STREAMING SERVICE, MAX UL TX POWER OF INTERACTIVE SERVICE and MAX UL TX POWER OF BACKGROUND SERVICE) which correspond to the maximum allowed transmit power of four classes of services: conversational, streaming, interactive and background respectively.

Parameter name Max UL TX power of conversational service

Parameter ID MAXULTXPOWERFORCONV

GUI range -5033


Default value 24


MML command ADD CELLCAC; MOD CELLCAC

Description: The maximum UL transmit power for conversational service in a specific cell. It is based on the UL coverage requirement of the conversational service designed by the network planning.


1-20

Parameter name Max UL TX power of streaming service

Parameter ID MAXULTXPOWERFORSTR

GUI range -5033


Default value 24



Description: The maximum UL transmit power for streaming service in a specific cell. It is based on the UL coverage requirement of the streaming service designed by the network planning.

Parameter name Max UL TX power of interactive service

Parameter ID MAXULTXPOWERFORINT

GUI range -5033


Default value 24



Description: The maximum UL transmit power for interactive service in a specific cell. It is based on the UL coverage requirement of the interactive service designed by the network planning.

Parameter name Max UL TX power of background service

Parameter ID MAXULTXPOWERFORBAC

GUI range -5033


Default value 24



Description: The maximum UL transmit power for background service in a specific cell. It is based on the UL coverage requirement of the background service designed by the network planning.


1-21

Recommendation:

The above four parameters define the maximum uplink transmit power when transmitting the services in a cell. The bigger these parameters are, the wider the coverage of the corresponding services will be. When the downlink coverage is exceeded, the uplink coverage and downlink coverage of the service will become unbalanced. If these parameters are too small, the uplink coverage will probably be smaller than the downlink coverage of the service. If there is no special requirement, use the default value.

Rate Matching The purposes of rate matching are as follows:

To enable a CCTrCH to multiplex data bits from multiple traffic sub-flows, the system matches traffic rates to physical channel rates.

To meet the different QoS requirements of various services, the system adjusts the coding redundancy degree of each channel. It is equivalent to changing the bit energy (Eb) of each channel and balancing the power among different channels. This method improves power usage and reduces interference. The higher the service QoS requirement is, the higher the corresponding RMA value. According to the RMA value of each traffic channel, the rate matching mechanism repeats more bits of the services with higher QoS requirements. Comparatively, it repeats less, even deletes some bits of the services with lower QoS requirement. Thus, it meets different QoS requirements through adjusting the bit redundancy degree of each transport channel.

Parameter name UL rate matching attribute

Parameter ID ULRATEMATCHINGATTR

GUI range 1256


Default value Values according to SRB and RAB


MML command

ADD TYPSRBSEMISTATICTF/ MOD TYPSRBSEMISTATICTF/ ADD TYPRABSEMISTATICTF/ MOD TYPRABSEMISTATICTF/

Description: Rate matching attribute (RMA) is a semi-static parameter provided by the upper layer for each traffic channel according to QoS. It represents the weight of processing (repeating or deleting) data bits on the corresponding transport channel during rate matching. This parameter is valid in the case of multiplexing of transport channel, that is, when multiple transport channels are combined into a CCTrCH. It is used to compare with the RMA values of other multiplexing transport channels.


1-22

Parameter name DL rate matching attribute

Parameter ID DLRATEMATCHINGATTR

GUI range 1256




MML command

ADD TYPSRBSEMISTATICTF/ MOD TYPSRBSEMISTATICTF/ ADD TYPRABSEMISTATICTF/ MOD TYPRABSEMISTATICTF/

Description: Rate matching attribute (RMA) is a semi-static parameter provided by the upper layer for each traffic channel according to QoS. It represents the weight of processing (repeating or deleting) data bits on the corresponding transport channel during rate matching. This parameter is valid in the case of multiplexing of transport channel, that is, when multiple transport channels are combined into a CCTrCH. It is used to compare with the RMA values of other multiplexing transport channels.

Rate matching attribute parameters are defined per RAB in the following table:

Typical Services ULRATEMATCHINGATTR DLRATEMATCHI

NGATTR CS Domain RAB

12.2bps AMR 137:130:161 137:130:161

64kbps Conversational / Unknown 110 110



28.8kbps Conversational / Unknown 100 100

57.6kbps Streaming 100 100

PS Domain RAB





256kbps Streaming 100 100




1-23

Typical Services ULRATEMATCHINGATTR DLRATEMATCHI

NGATTR 64kbps Streaming 100 100




384kbps Background 100 100







8 kbps Background 140 140

384kbps Interactive 100 100







8 kbps Interactive 140 140

Signaling RB

3.4kbps SRB 180 180

13.6kbps SRB 180 180

Power Difference Between DPCCH And DPDCH The uplink DPCCH and DPDCH(s) are transmitted on different codes. In order to meet a given QoS requirement on the transport channels whatever the transport format they use, various power differences between DPDCH and DPCCH are defined through gain factors, called c for DPCCH and d for DPDCH. There are two ways of controlling the gain factors of the DPCCH code and the DPDCH codes for different TFCs in normal (non-compressed) frames: c and d are signalled for the TFC, or


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c and d is computed for the TFC, based on the signalled settings for a reference TFC.

3GPP allows combinations of these two methods to be used to associate c and d values with all TFCs in the TFCS. These two methods are described in subsections 5.1.2.5.2 and 5.1.2.5.3 respectively of TS25.214. Several reference TFCs may be signaled from higher layers.

For Huawei, a mix of these techniques is effectively applied, which requires the RNC to compute and signal all TFC offsets when required. The RNC computes a new power offset for each required TFC dynamically using a single set of configurable reference values (corresponding to parameters Reference BetaC and Reference BetaD) stored for each pre-defined RABs or SRBs. This computed TFC specific offset is then signaled to the UE.

Parameter name Reference BetaC

Parameter ID BETAC

GUI range 115




MML command ADD TYPSRBBASIC/MOD TYPSRB/ADD TYPRABBASIC/MOD TYPRAB

Description: Power occupation ratio of the control part of reference TFC.

Parameter name Reference BetaD

Parameter ID BETAD

GUI range 115




MML command ADD TYPSRBBASIC/MOD TYPSRB/ADD TYPRABBASIC/ MOD TYPRAB

Description: Power occupation ratio of the data part of reference TFC.

UL reference power offset parameters (c,ref and d,ref) are defined in the following table:


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Typical Services c,ref :::: d,ref CS Domain RAB

12.2bps AMR 12:15

64kbps Conversational / Unknown 6:15



28.8kbps Conversational / Unknown 13:15

57.6kbps Streaming 7:15

PS Domain RAB





256kbps Streaming 4:15







384kbps Background 4:15







8 kbps Background 15:11

384kbps Interactive 4:15






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Typical Services c,ref :::: d,ref 32kbps Interactive 9:15


8 kbps Interactive 15:11

Signaling RB

3.4kbps SRB 15:12

13.6kbps SRB 12:15

Configuration Rule and Restriction: Either Reference BetaC or Reference BetaD must be set to 15 for each instance of UL reference power offset.

The gain factors (c and d) are computed for certain TFCs, based on the settings for a reference TFC with the formula defined in subsection 5.1.2.5.3 of TS25.214.

In Huawei implementation, in the case of RAB combination, the radio bearer specific reference values to be used are those belonging to the radio bearer whose maximum rate TF has the highest bit rate of the radio bearers being combined. For example, for the combination of the 3.4 kbps SRB service, 384 kbps background service, and 12.2 kbps AMR service, the reference power offset values applied are those belonging to the maximum rate TF (12x336) of 384 kbps background radio bearer. First Radio Link Establishment When commanded by higher layers, the TPC commands sent on a downlink radio link from NodeBs that have not yet achieved uplink synchronization will follow a pattern as follows:

If the radio link is part of the first radio link set sent to the UE and if the value "n" obtained from the parameter DL POWER CONTROL MODE 1 is different from 0, then:

The TPC pattern shall consist of n instances of the pair of TPC commands ("0", "1"), followed by one instance of TPC command "1", where ("0","1") indicates the TPC commands to be transmitted in two consecutive slots.

The TPC pattern continuously repeat but shall be forcibly re-started at the beginning of each frame where CFN mod 4 = 0.

In addition,

The TPC pattern shall consist of only TPC commands "1". The TPC pattern shall terminate when uplink synchronization is achieved.


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Parameter name DL power control mode 1

Parameter ID DLTPCPATTERN01COUNT

GUI range 030


Default value 10


MML command ADD CELLSETUP/MOD CELLSETUP

Description: DL transmit power control (TPC) mode of the first radio link set before completion of UL synchronization.

Caution:

In order to change the value of the DL POWER CONTROL MODE 1 parameter through MOD CELLSETUP, the cell shall be firstly de-activated through DEA CELL.

Transmit Power Control in the UL DPCCH Power Control Preamble An uplink DPCCH Power Control Preamble (PC Preamble) is a period of uplink DPCCH transmission prior to the start of the uplink DPDCH transmission in order to ensure that the inner loop power control has converged when the transmission of the data bits begins. It consists of a given number of DPCCH slots transmitted prior to the data transmission on DPDCH. The RNC transmits the PC Preamble parameter (number of DPCCH preamble slots) in the Uplink DPCH power control info IE using the RRC signaling.

In addition to the PC Preamble delay, the mobile will not send any data on signaling radio bearers during the number of frames indicated in the SRB delay IE, sent through RRC signaling in the Uplink DPCH power control info IE.

Considering the application scenarios, different values for PC Preamble and SRB delay parameters are configured.

In the case of RRC connection establishment, PC Preamble and SRB delay are respectively defined by parameters RRC PROC DPDCH PC PREAMBLE LENGTH and RRC PROC SRB DELAY.

In the case of hard handover, PC Preamble and SRB delay are respectively defined by parameters HHO PROC DPDCH PC PREAMBLE LENGTH and HHO PROC SRB DELAY.


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Parameter name RRC Proc DPDCH PC preamble length

Parameter ID RRCPROCPCPREAMBLE

GUI range 07

Physical range& unit Frame

Default value 0


MML command ADD CELLCAC/MOD CELLCAC

Description: DPDCH power control preamble length in DCH RRC process.

Parameter name RRC Proc SRB delay

Parameter ID RRCPROCSRBDELAY

GUI range 07


Default value 7



Description: Delay of SRB in DCH RRC process.

Parameter name HHO Proc DPDCH PC preamble length

Parameter ID HHOPROCPCPREAMBLE

GUI range 07


Default value 0



Description: DPDCH power control preamble length in DCH HHO process.


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Parameter name HHO Proc SRB delay

Parameter ID HHOPROCSRBDELAY

GUI range 07

Physical range& unit Frame.

Default value 7



Description: Delay of SRB in DCH HHO process.

Inner loop power control is thus applied on the DPCCH only, in a first time, starting from the initial DPCCH transmit power determined by the open loop power control process. Then, once PC Preamble DPCCH slots have been transmitted and SRB delay slots passed, data starts to be transmitted on the DPDCH at an initial transmit power deduced from the current DPCCH transmit power and DPDCH/DPCCH power difference (using c and d gain factors).

II. Downlink Open-Loop Power Control

1) Downlink Open-Loop Power Control on Common Channel For the common channels, DL open-loop power control is to determine how much power is allocated to the PCPICH, P-SCH, S-SCH, P-CCPCH, S-CCPCH, AICH, and PICH channels.

As mentioned previously, the P-CPICH power is defined by the PCPICH TRANSMIT POWER parameter as an absolute value in dBm. The power of all other common channels is defined in relation with the PCPICH TRANSMIT POWER parameter.

The following tables describe which parameter is used to determine the power for each common channel:


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Parameter name PSCH transmit power

Parameter ID PSCHPOWER

GUI range -350150

Physical range& unit -3515, step: 0.1 (dB) Default value -50


MML command ADD PSCH/MOD CELL

Description: The offset of the PSCH transmit power from the PCPICH transmit power in a cell.

Parameter name SSCH transmit power

Parameter ID SSCHPOWER

GUI range -350150

Physical range& unit -3515, step: 0.1(dB) Default value -50


MML command ADD SSCH/MOD CELL

Description: The offset of the SSCH transmit power from the PCPICH transmit power in a cell

Recommendation:

These two parameters (PSCH TRANSMIT POWER and SSCH TRANSMIT POWER) can be adjusted through measurement in the actual environment so that the transmit powers of the synchronization channels just satisfy the UE receiving demodulation requirement. Specifically, when UEs receive signals at different locations within the range of the cell, the transmit power should be just enough to ensure that the UE can implement fast synchronization in most areas at the verge of the cell. Neither P-SCH nor S-SCH has come through channel code spectrum spread, so they produce more serious interference than other channels do, especially for nearend users. Therefore, the value should not be too big.


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Parameter name BCH transmit power

Parameter ID BCHPOWER

GUI range -350150 Physical range& unit -3515, step: 0.1(dB) Default value -20


MML command ADD BCH/MOD CELL

Description: The offset of the BCH transmit power from the PCPICH transmit power in a cell.

Recommendation:

The BCH TRANSMIT POWER parameter can be adjusted and optimized through measurement in the actual environment. When UEs receive signals at different locations within the range of the cell, the transmit power should be just enough to ensure the correct demodulation of the information carried on the channel in most areas at the verge of the cell. This setting of this parameter should not be too big, so as to avoid unnecessary waste of the transmit power. If the setting of this parameter is too small, the user at the verge of the cell will fail to receive the system information correctly, and the downlink common channel coverage will be influenced, which will affect cell coverage; if the setting is too big, other channels will be interfered, the power resources will be occupied, and consequently the cell capacity will be influenced.

Parameter name Max transmit power of FACH

Parameter ID MAXFACHPOWER

GUI range -350150 Physical range& unit -3515, step: 0.1(dB) Default value 10


MML command ADD FACH/MOD SCCPCH

Description: The offset between the FACH transmit power and PCPICH transmit power in a cell.

Recommendation:


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Set the maximum FACH transmit power to an appropriate value that is just enough to ensure the target BLER. If the setting of this parameter is too small, the UE at the cell verge will fail to receive correctly the services and signaling borne over the FACH, resulting in influence on the downlink common channel coverage and the cell coverage; if it is too big, other channels will be interfered, the power resources will be occupied, and consequently the cell capacity will be influenced.

Caution:

In order to change the value of the MAX TRANSMIT POWER OF FACH parameter if the current cell is on-going and there is one and only one SCCPCH in this cell, or in order to change the configuration of the SCCPCH with the smaller SCCPCH ID when there are two SCCPCHs in this cell, the cell shall be firstly de-activated through DEA CELL.

Parameter name PCH power

Parameter ID PCHPOWER

GUI range -350150 Physical range& unit -3515, step: 0.1(dB) Default value -20


MML command ADD PCH/MOD SCCPCH

Description: The offset between the PCH transmit power and PCPICH transmit power in a cell.

Recommendation:

The default value of the PCH POWER parameter is -20, namely -2 dB. If this parameter is too small, the UE at the cell verge will fail to receive paging messages correctly, and this will influence downlink common channel coverage and cell coverage; if it is too big, other channels will be interfered, the downlink transmit power will be occupied, and consequently the cell capacity will be influenced.


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Parameter name AICH power offset

Parameter ID AICHPOWEROFFSET

GUI range -225 Physical range& unit dB

Default value -6


MML command ADD CHPWROFFSET/MOD AICHPWROFFSET

Description: The difference between the transmit power of AICH and that of PCPICH.

Recommendation:

The default value of the AICH POWER OFFSET parameter is -6, namely -6 dB. An appropriate transmit power value should be set for AICH to ensure that all users at cell verge can receive the access indication. However, to avoid waste of the power, the setting of the transmit power should not be too big.

Parameter name PICH power offset

Parameter ID PICHPOWEROFFSET

GUI range -105 Physical range& unit dB

Default value -7


MML command ADD CHPWROFFSET/MOD PICHPWROFFSET

Description: The difference between the transmit power of PICH and that of PCPICH.

Recommendation:

The default value of the PICH POWER OFFSET parameter is -7, namely -7 dB. If this parameter is too small, the UE at the cell verge will fail to receive paging messages correctly, which will probably result in misoperation in reading PCH channel and waste of the UE battery and affect the downlink common channel coverage and the cell coverage; if it is too big, other channels will be interfered, the power resources will be occupied, and consequently the cell capacity will be influenced.


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2) Downlink Open-Loop Power Control on Dedicated Channel (DPDCH) The aim of the DL open-loop power control on DPDCH is to determine the transmit power of the traffic (dedicated) channel based on the downlink measurement report of the UE. Both UE and UTRAN shall take part in downlink open-loop power control on the DPDCH, as shown in Figure 1-11.

Determine the downlink initial power control

RACH reports the measured value

Measure CPICH Ec/N0

DCH

Figure 1-11 Downlink open-loop power control on the DPDCH

The following gives a formula to calculate the initial power of the DPDCH when a traffic (dedicated) channel is set up:

= Total

CPICH

CPICHDLinitial P

)0N

Ec(P)

0NEb(

WRP

Where:

R is the requested data bit rate by the user. W is the chip rate.

DL)0N/Eb(

is the Eb/No target to ensure the service quality. In Huawei

implementation, RNC searches for a value of Eb/No target dynamically using a set of pre-defined values corresponding to the specific cell environment type, code type, coding rate and BLER target. For detailed information, refer to the Load Control.

(Ec/N0)CPICH is the ratio of received energy per chip to noise spectral density of CPICH received by UE.

is the orthogonality factor in the downlink. In the WCDMA system, orthogonal codes are employed in the downlink to separate the users, and without any multi-path propagation on the orthogonality remains when the Node B signal is received by the mobile station. However, if there is sufficient delay spread in the radio channel, part of the base station signals will be regarded as multiple access


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interference by the mobile station. The orthogonality of 1 corresponds to perfectly orthogonal users.

Note:

In Huawei implementation, in the above formula is set to 0. Ptotal is the carrier power measured at the NodeB and reported to the RNC.

Radio Link Reconfiguration Power Setting When reconfiguring a radio link, the new physical channel may not have the same power as the previous one (because of different SF, and so on). It is not specified, however, in 3GPP protocol that the RNC can send a new initial power for the new configuration in the RADIO_LINK_RECONFIGURATION_PREPARE message, which provides the NodeBs with the new physical/transport channel configuration.

Thus, the NodeB will adjust the downlink power through the process of inner-loop power control.

Initial Power Setting In Soft Handover In order to prevent a waste of downlink power while adding a new leg in the active set, a new adjustment for power of the new leg is used. Based on the above calculation as used for the initial power of the DPDCH when a traffic (dedicated) channel is set up, the power required by a new leg introduced in the active set shall be decreased by an offset, which is defined by the INITIAL POWER OFFSET FOR SHO parameter.

Parameter name Initial power offset for SHO

Parameter ID SHOINITPWRPO


Default value 15



Description: Initial DL power offset for a new added RL in SRNC.

Upper and Lower Limits of DL DPDCH Power The downlink dedicated traffic channel is limited by an upper and lower limit for each radio link. This limitation is set through the RL MAX DL TX POWER and RL MIN DL TX


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POWER parameters. Both parameters are provided a value for the different data rate of radio access bearers. So they correspond to a set of values rather than a single value.

Parameter name RL Max DL TX power

Parameter ID RLMAXDLPWR

GUI range -350150 Physical range& unit -3515; step: 0.1(dB) Default value Values according to data rate of RABs


MML command ADD CELLRLPWR/MOD CELLRLPWR

Description: 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.

Parameter name RL Min DL TX power

Parameter ID RLMINDLPWR

GUI range -350150 Physical range& unit -3515; step: 0.1(dB) Default value Values according to data rate of RABs


MML command ADD CELLRLPWR/MOD CELLRLPWR

Description: 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.

Configuration Rule and Restriction: The parameters RL MAX DL TX POWER and RL MIN DL TX POWER must verify the following relationship:

RL MIN DL TX POWER RL MAX DL TX POWER

Typical Services RL MAX DL TX POWER

RL MIN DL TX POWER CS Domain RAB

12.2bps -30 -180

28.8kbps -20 -170


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Typical Services RL MAX DL TX POWER

RL MIN DL TX POWER 32kbps -20 -170

57.6kbps -10 -160

64kbps 30 -120

PS Domain RAB

384kbps 40 -110

256kbps 20 -170

144kbps 0 -150

128kbps 0 -150

64kbps -20 -170

32kbps -40 -190

16kbps -60 -210

8kbps -80 -230

Power Difference between DPCCH and DPDCH For the downlink DPCH, the relative transmit power offset between DPCCH fields and DPDCHs is determined by the network. The TFCI, TPC and pilot fields of the DPCCH are offsets related to the power of DPDCHs by PO1, PO2, and PO3 dB respectively. The power offsets PO1, PO2 and PO3 are defined by the TFCI POWER OFFSET, TPC POWER OFFSET, and PILOT POWER OFFSET parameters respectively.

These power offsets cannot be reconfigured during the connection. These offsets are radio link specific, which are identical for all TFC in the TFCS, whereas for the uplink the gain factors are TFC-dependent.

Parameter name TFCI power offset

Parameter ID TFCIPO

GUI range 024 Physical range& unit 06; step: 0.25(dB) Default value 0


MML command SET FRC

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


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Parameter name TPC power offset

Parameter ID TPCPO



MML command SET FRC

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

Parameter name Pilot power offset

Parameter ID PILOTPO



MML command SET FRC

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

The downlink transmit power control procedure controls simultaneously the power of a DPCCH and its corresponding DPDCHs. The power control loop adjusts the power of the DPCCH and DPDCHs with the same amount, that is to say, the relative power difference between the DPCCH and the DPDCHs is not changed.

1.6.3 Inner-Loop Power Control

Inner-loop power control is also called fast closed-loop power control. It controls the transmit power according to the information returned from the peer physical layer. The UE and the NodeB can adjust the transmit power according to the RX SIR of the peer end, to compensate the fading of radio links.

Inner-loop power control consists of uplink inner-loop power control and downlink inner-loop power control, and they work separately.


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I. Uplink Inner-Loop Power Control

Uplink inner-loop power control is used to control the power of the uplink radio links. In fact, uplink inner-loop power control is executed on the DPCCH, and related DPDCH transmit power is calculated from DPCCH transmit power according to DPDCH/DPCCH power ratio (d /c). For details, refer to 1.6.2 Open-Loop Power Control.

The RNC sends the SIR target to the NodeB and then the NodeB compares the estimated SIR with the SIR target of uplink DPCCH pilot symbol once every timeslot.

If the estimated SIR is greater than the SIR target, the NodeB sends a TPC command down to the UE on the downlink DPCCH TPC field.

Otherwise, the NodeB sends a TPC command "Up".

Note:

The "Up" command means TPC = 1 and the "Down" command means TPC = 0.

For the SFISCPRSCPSIR */= ,

The Received Signal Code Power (RSCP) is unbiased measurement of the received power on one code.

The Interference Signal Code Power (ISCP) is the interference on the received signal, and SF=the spreading factor used on the DPCCH.

TPCSIR estimation andcompare with SIR target

SIR target

NodeB

1500 Hz

UE

Figure 1-12 Uplink inner-loop power control

The following describes the uplink inner-loop power control:

Single Radio Link It means that the UE will receive only one TPC in each slot. The NodeB will estimate the SIR value and sends TPC to the UE according to the comparison between SIR target and SIR estimated result.


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If the estimated SIR is greater than the SIR target, the NodeB sends a TPC command down to the UE on the downlink DPCCH TPC field. Otherwise, the NodeB sends a TPC command up, where the up command means TPC = 1 and the down command means TPC = 0.

When the UE receives the TPC, UE will adjust uplink transmit power according to the Power Control Algorithm (PCA). There are two types of inner-loop PCA algorithm: PCA1 and PCA2. The RNC configures the PCA algorithm based on the POWER CONTROL ALGORITHM SELECTION parameter.

Parameter name Power control algorithm selection

Parameter ID PWRCTRLALG

GUI range ALGORITHM1, ALGORITHM2.


Default value ALGORITHM1


MML command SET FRC

Description: This parameter is used to inform the UE of the method for translating the received Transmit Power Control (TPC) commands. In other words, it is used to select UL power control algorithm.

Configuration Rule and Restriction:

Huawei sets the POWER CONTROL ALGORITHM SELECTION parameter to algorithm1 as default value for all power control configurations

PCA1: UE adjusts uplink transmit power for each slot; the step of PCA1 should be 1dB or 2dB by UL CLOSED LOOP POWER CONTROL STEP SIZE parameter.


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Parameter name UL closed loop power control step size

Parameter ID ULTPCSTEPSIZE


Default value 1


MML command SET FRC

Description: The step size of the closed loop power control performed on UL DPCCH. This parameter is mandatory when the parameter [Power control algorithm selection] is set as "ALGORITHM1".

The following table lists the TPC command corresponding to the specific TPC at PCA1 algorithm:

TPC TPC_cmd

0 -1

1 1

PCA2: The UE adjusts the uplink transmit power for each 5-slot cycle and the step is 1 dB fixedly.

The following table lists the TPC command corresponding to the specific TPC at PCA2 algorithm:

TPC TPC_cmd

0,0,0,0,0 0,0,0,0,-1

1,1,1,1,1 0,0,0,0,1

Else 0,0,0,0,0

Softer Handover It means that the UE will receive more than one TPC in each slot, but all the TPCs are the same from each cell which belongs to one NodeB.

The UE will combine the DL TPC by Maximum Ratio Combining (MRC) algorithm. Therefore, other processing is the same as that in scenario1 (single radio link). Soft handover It means that the UE will receive more than one TPC in each slot, and all the TPCs come from different NodeBs.


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On the NodeB side, there are two phases to process power control during the soft handover procedure:

Uplink synchronization phase:

The NodeB should send durative TPC=1 to newly-added radio link before successful synchronization.

Multi-radio link phase: Each NodeB and each cell will estimate the SIR individually and the general TPC individually. Therefore, the UE may receive different TPC from different RLS.

On the UE side, the UE will receive different TPCs from different RLS at the same time. Therefore, the UE should combine all the TPCs which come from different NodeBs to get TPC commands and adjust uplink transmit power according to the combined TPC commands.

There is different UE TPC combination algorithm for PCA1 and PCA2.

In case of PCA1

First, the UE shall conduct a soft symbol decision W i on each of the power control commands TPCi, where i = 1, 2, , N (N is greater than 1 and is the number of TPC commands from radio links of different radio link sets.) That may be the result of a first phase of combination.

Finally, the UE derives a combined TPC command, TPC_cmd, as a function of all the N soft symbol decisions W i:

- TPC_cmd = (W1, W2, WN), where TPC_cmd can take the values 1 or -1. The function shall fulfill the following criteria:

If the N TPCi commands are random and uncorrelated, with equal probability of being transmitted as "0" or "1", the probability that the output of is equal to 1 shall be greater than or equal to 1/(2N), and the probability that the output of is equal to -1 shall be greater than or equal to 0.5. Further, the output of shall equal 1 if the TPC commands from all the radio link sets are reliably 1, and the output of shall equal -1 if a TPC command from any of the radio link sets is reliably 0.

Then, after deriving a combined TPC_cmd, the UE will adjust uplink transmit power as pre-defined power step which is configured by the RNC.

In case of PCA2

The UE shall make a hard decision on the value of each TPCi, where i = 1, 2, , N (N is the number of TPC commands from radio links of different radio link sets.) That may be the result of a first phase of combination.


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The UE shall follow this procedure for 5 consecutive slots, resulting in N hard decisions for each of the 5 slots. The sets of 5 slots shall be aligned to the frame boundaries and there shall be no overlap between each set of 5 slots.

The value of TPC_cmd is zero for the first 4 slots. After 5 slots have elapsed, the UE shall determine the value of TPC_cmd for the fifth slot in the following way:

The UE first determines one temporary TPC command, TPC_tempi, for each of the N sets of 5 TPC commands as follows:

- If all 5 hard decisions within a set are "1", TPC_tempi = 1.

- If all 5 hard decisions within a set are "0", TPC_tempi = -1.

- Otherwise, TPC_tempi = 0.

Finally, the UE derives a combined TPC command for the fifth slot, TPC_cmd, as a function of all N temporary power control commands TPC_tempi:

TPC_cmd (5th slot) = (TPC_temp1, TPC_temp2, , TPC_tempN), where TPC_cmd (5th slot) can take the values 1, 0 or 1, and is given by the following definition: TPC_cmd is set to -1 if any of TPC_temp1 to TPC_tempN are equal to -1.

Otherwise, TPC_cmd is set to 1 if 5.0_1

1>

=

N

iitempTPCN

.

Otherwise, TPC_cmd is set to 0.

Then, after deriving a combined TPC_cmd, the UE will adjust uplink transmit power as 1dB step.

II. Downlink Inner-Loop Power Control

Downlink inner-loop power control is used to control the power of the downlink DPCH.

The UE receives the SIR target from higher layers, estimates the downlink SIR from the pilot symbols of the downlink DPCH, and compares this estimated SIR with the SIR target.

If the estimated SIR is greater than the SIR target, the UE sends a TPC command "down" to the NodeB.

Otherwise, the UE sends a TPC command up.


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TPC SIR estimation andcompare with SIR target

SIR target

NodeB

1500 Hz

UE

Figure 1-13 Downlink inner-loop power control

The following describes the downlink inner-loop power control:

Single Radio Link The downlink power control can be classified into two modes.

The UE shall check the downlink power control mode (DPC_MODE) before the TPC command is generated:

If DPC_MODE = 0,

The UE sends a unique TPC command in each slot and the TPC command generated is transmitted in the first available TPC field in the uplink DPCCH.

If DPC_MODE = 1,

The UE repeats the same TPC command over 3 slots and the new TPC command is transmitted such that there is a new command at the beginning of the frame.

The DPC_MODE parameter is a UE-specific parameter controlled by the UTRAN. The DPC mode can be set by the DL POWER CONTROL MODE parameter.


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Parameter name DL power control mode

Parameter ID DPCMODE

GUI range SINGLE_TPC, TPC_TRIPLET_IN_SOFT, TPC_AUTO_ADJUST.


Default value SINGLE_TPC


MML command SET FRC

Description: SIGNLE_TPC, a fast power control mode, indicates that a unique TPC command is sent in each time slot on DPCCH. TPC_TRIPLET_IN_SOFT, a slow power control mode, indicates that the same TPC command is sent in three time slots, it is applicable to soft handover and it can decrease the power deviation. TPC_AUTO_ADJUST, an automatically adjusted mode, indicates that the value of DPC_MODE can be modified by sending the message "ACTIVE SET UPDATE" to UE.


Huawei sets the DL POWER CONTROL MODE parameter to singel_TPC as default value for all power control configurations

Upon receiving the TPC commands, the UTRAN shall adjust its downlink DPCCH/DPDCH power accordingly.

If DPC_MODE = 0, the UTRAN shall estimate the transmitted TPC command TPCest to be 0 or 1, and shall update the power every slot.

If DPC_MODE = 1, the UTRAN shall estimate the transmitted TPC command TPCest over three slots to be 0 or 1, and shall update the power every three slots.

After estimating the k:th TPC command, the UTRAN shall adjust the current downlink power P(k-1) [dB] to a new power P(k) [dB] according to the following formula: P(k) = P(k - 1) + PTPC(k) + Pbal(k) Where:

PTPC(k) is the k:th power adjustment due to the inner loop power control. Pbal(k) [dB] is a correction according to the downlink power control procedure for

balancing radio link powers towards a common reference power. For a single radio link, Pbal equals 0.

PTPC(k) is calculated according to the following: If the value of Limited Power Increase Used parameter is 'Not used', then,


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=

=+=

0)(TPCif1)(TPCif)(P

estTPC

estTPCTPC k

kk

, [dB] The limited power increase used parameter could be set by the parameter of INNER_LOOP_DL_LMTED_PWR_INC_SWITCH.

Parameter name Power control algorithm switch

Parameter ID INNER_LOOP_DL_LMTED_PWR_INC_SWITCH

GUI range 1(ON), 0(OFF) Physical range& unit None

Default value 0


MML command SET CORRMALGOSWITCH

Description: When it is checked, limited power increase algorithm is applied in the inner loop power control.

If the value of limited power increase used parameter is 'Used', then, the k:th inner loop power adjustment shall be calculated through the following formula:

=

+=


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Caution:

In order to change the value of the POWER INCREASE LIMIT parameter through MOD CELLSETUP, the cell shall be firstly de-activated through DEA CELL.

Where:

=

=1

indow_Sizeveraging_WDL_Power_A)()(

k

kiTPCsum iPk

is the temporary sum of the last DL_Power_Averaging_Window_Size inner loop power adjustments (in dB). DL_Power_Averaging_Window_Size can be set by the DL POWER WINDOW AVERAGE SIZE parameter.

Parameter name DL power window average size

Parameter ID DLPOWERAVERAGEWINDOWSIZE

GUI range 160 Physical range& unit slot.

Default value 20


MML command ADD CELLSETUP/MOD CELLSETUP

Description: Content: UTRAN calculates the increase of DL transmit power within the period defined via this parameter to determine whether the increase exceeds PowerRaiseLimit. If so, UTRAN will not increase the power even when it receives the command to raise the power.

Caution:

In order to change the value of the DL POWER WINDOW AVERAGE SIZE parameter through MOD CELLSETUP, the cell shall be firstly de-activated through DEA CELL.

The power control step size TPC can be any of the four values of 0.5, 1, 1.5 and 2 dB and be set by the FDD DL POWER CONTROL STEP parameter.


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Parameter name FDD DL power control step size

Parameter ID FDDTPCDLSTEPSIZE

GUI range STEPSIZE_0.5DB, STEPSIZE_1DB, STEPSIZE_1.5DB, STEPSIZE_2DB.

Physical range& unit 0.5, 1, 1.5, 2(dB) Default value STEPSIZE_1DB


MML command SET FRC

Description: Content: The step size of the closed loop power control performed on DL DPCH in Frequency Division Duplex (FDD) mode.

Scenario Softer Handover In the case of softer handover, the NodeB gets one TPC after MRC combination. Then the downlink power procedure is the same as that in single radio link.

Soft Handover For details about the soft handover, refer to the description in the subsection 1.6.5 Downlink Power Balance.

1.6.4 Outer-Loop Power Control

The aim of outer-loop power control is to maintain the communication quality at the level required by the service bearer through adjustment of the SIR target. This control acts on each DCH belonging to the same RRC connection.

The SIR target needs to be adjusted when the UE speed or the multi-path propagation environment changes, so that the communication quality can maintain the same. If a fixed SIR target is selected, the resulting quality of the communication might be too low or too high, which may cause an unnecessary power rise in most situations.

I. Uplink Outer-Loop Power Control

The uplink quality is observed after macro diversity selection combining in the RNC. Therefore, uplink outer-loop power control is performed in the SRNC.

The SRNC compares the RX BLER with the BLER target. If the RX BLER is greater than the BLER target, the SRNC increases the SIR target; otherwise, decreases.

After adjusting the SIR target, the SRNC sends the new SIR target through FP frames to all NodeBs for uplink inner loop power control.


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NodeB

UERNC

Inner loopOuter loop

Sent TPCSIR target settting

SIR measurementand comparing

BLER targetsettting

BLERmeasurement

and comparing

Figure 1-14 Uplink outer-loop power control procedure

The uplink outer-loop power control for all UEs can be deactivated by OLPC_SWITCH; or by setting SIR ADJUSTMENT STEP to zero to deactivate uplink outer loop power control for different services.

Parameter name Power control algorithm switch

Parameter ID OLPC_SWITCH

GUI range 0, 1.

Physical range& unit OFF, ON (NONE) Default value 1


MML command SET CORRMALGOSWITCH

Description: When it is ON, RNC will update the uplink SIR TARGET of RLs on the NODEB side by IUB DCH FP signals.

Initial SIR Target Setting The initial SIR target value is provided by the RNC to the NodeB through the SIR INIT TARGET VALUE parameter which is service-dependent. This value is transmitted to the NodeB using NBAP signaling at each RADIO LINK SETUP or RADIO LINK RECONFIGURATION PREPARE.


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Parameter name SIR init target value

Parameter ID INITSIRTARGET

GUI range 0255 Physical range& unit -8.217.3; step: 0.1(dB) Default value Refer to Table 1-3.


MML command ADD TYPSRBOLPC/MOD TYPSRBOLPC/ ADD TYPRABOLPC/MOD TYPRABOLPC

Description: This parameter defines the initial SIR target value of Outer Loop Power Control algorithm. Value 0 corresponds to -8.2 dB, value 10 to -7.2 dB, and value 255 to 17.3 dB.


For the same SRB or TRB, SIR INIT TARGET VALUE, MAXIMUM SIR TARGET and MINIMUM SIR TARGET must verify the following relationship: MINIMUM SIR TARGET SIR INIT TARGET VALUE MAXIMUM SIR TARGET

SIR Target Adjustment The outer-loop power control adjusts SIR target through a OLPC ADJUSTMENT PERIOD parameter as follows:

]*)(*)()()),1(()1(tar[SIRtar(n) factoriStep

iBLERiBLERinBLER

nSIRMAXtar

tarmeas +

In the above formula, meanings of the parameters are as follows:

i is the ith transmission channel. n is the nth adjustment period. SIRtar(n) is the SIR target used by the nth adjustment period which could be set by

parameter OLPC ADJUSTMENT PERIOD. MAX is the maximum value in the total i transmission channels.

BLERmeas(n,i) is the instantaneous )i()i(ErrTb),(meas

nTb

ninBLER measured for the

ith transmission channel in the nth adjustment period. - Tb(n,i) is the number of error blocks in the TBs received from the ith transmission channel in the nth adjustment period. - ErrTb(n,i) is the number of error blocks indicated by the CRCI in the Tb(n,i) that is received from the ith transmission channel.


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BLERtar(i) is the BLER target of the ith transmission channel, which could be set by parameter SERVICE DCH_BLER TARGET VALUE.

Step(i) is the adjustment step of the ith transmission channel, which could be set by parameter SIR ADJUSTMENT STEP.

factor is the adjustment factor which could be set by parameter SIR ADJUSTMENT COEFFICIENT.

Parameter name OLPC adjustment period Parameter ID SIRADJUSTPERIOD

GUI range 1100 Physical range& unit 101000, step: 10(ms) Default value Refer to Table 1-3.



Description: Outer Loop Power Control varies with radio environment. A fast changing radio environment leads to a shorter Outer Loop Power Control adjustment period, while a slower changing one makes the period longer.

Parameter name SIR measurement filter coefficient

Parameter ID SIRMEASFILTERCOEF

GUI range D0, D1, D2, D3, D4, D5, D6, D7, D8, D9, D11, D13, D15, D17, D19.

Physical range& unit 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 11, 13, 15, 17, 19(NONE) Default value D0


MML command SET OLPC

Description: The filter coefficient used for SIR measurement.


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Parameter name SIR adjustment coefficient Parameter ID SIRADJUSTFACTOR

GUI range 110 Physical range& unit 0.11; step: 0.1(NONE) Default value 10


MML command SET OLPC/ADD CELLOLPC/MOD CELLOLPC

Description: It is used to adjust the best OLPC step when the OLPC algorithm is given.

Parameter name BLER target value

Parameter ID BLERQUALITY

GUI range -630 Physical range& unit 5*10^(-7) 1(NONE) Default value Refer to Table 1-3.


MML command ADD TYPSRBOLPC/MOD TYPSRBOLPC/ADD TYPRABOLPC/MOD TYPRABOLPC

Description: If signalling is carried over DCH, this parameter indicates the target transmission quality of DCH, that is, DCH BLER target value at the radio interface. This parameter is related to QoS and is used by the CRNC to determine the SIR target for admission and power management. Use the formula below to get the parameter integer value: 10*Log10(BLER).


If the BLER TARGET VALUE parameter changes, the SIR ADJUSTMENT STEP parameter should modify synchronously. For the same SRB or TRB, if the default value of BLER TARGET VALUE and SIR ADJUSTMENT STEP are BLERquality1 and SirAdjustStep1, after change, the value of BLER TARGET VALUE and SIR ADJUSTMENT STEP are BLERquality2 and SirAdjustStep2, BLERquality1, SirAdjustStep1, BLERquality2, SirAdjustStep2 must verify the following relationship: (1-BLERquality1) * SirAdjustStep1/BLERquality1 = (1-BLERquality2) * SirAdjustStep2/BLERquality2


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Parameter name SIR adjustment step Parameter ID SIRADJUSTSTEP

GUI range 010000 Physical range& unit 010, step: 0.001(dB) Default value Refer to Table 1-3.



Description: Adjustment step of SIR target used by the outer loop power control algorithm.

The principles to adjust SIR target in case of multi-services are described as follows: The maximum value of SIR target among multiple services is used for the SIR

target adjustment. If one of the services requires increasing the SIR target, the maximum value is

used for the adjustment in the increase. Only when all the services require reducing the SIR target, the maximum value is

used for the adjustment in the decrease. SIR target adjustment limitation The service-dependent parameters MAXIMUM SIR INCREASE STEP and Maximum SIR decrease step limit the changes to the SIR target during any adjustment. Compute the quantity SIRtar = SIRtar(n+1) SIRtar(n): If ( SIRtar > 0 ) AND (SIRtar > MAXIMUM SIR INCREASE STEP)

Then SIRtar(n+1) = SIRtar(n) + MAXIMUM SIR INCREASE STEP If ( SIRtar < 0 ) AND (ABS(SIRtar) > MAXSIRSTEPDOWN)

Then SIRtar(n+1) = SIRtar(n) MAXSIRSTEPDOWN


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Parameter name Maximum SIR increase step

Parameter ID MAXSIRSTEPUP

GUI range 010000 Physical range& unit 010, step: 0.001(dB) Default value Refer to Table 1-3.


MML command ADD TYPRABOLPC/MOD TYPRABOLPC

Description: Maximum allowed SIR step-up within an Outer Loop Power Control adjustment period.

Parameter name Maximum SIR decrease step

Parameter ID MAXSIRSTEPDN

GUI range 010000 Physical range& unit 010, step: 0.001 (dB) Default value Refer to Table 1-3.


MML command ADD TYPSRBOLPC/MOD TYPSRBOLPC/ADD TYPRABOLPC/MOD TYPRABOLPC

Description: Maximum allowed SIR step-down within an Outer Loop Power Control adjustment period.

SIR target limitation

The service-dependent parameters MAXIMUM SIR TARGET and MINIMUM SIR TARGET limit the SIR target during any adjustment.


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Parameter name Maximum SIR target

Parameter ID MAXSIRTARGET




Description: This parameter defines the initial SIR target value of Outer Loop Power Control algorithm. Value 0 corresponds to -8.2 dB, value 10 to -7.2 dB, and value 255 to 17.3 dB.

Parameter name Minimum SIR target

Parameter ID MINSIRTARGET



MML command ADD TYPSRBOLPC/MOD TYPSRBOLPC/ ADD TYP

wcdma powercontrol 120618044133 phpapp02

Documents

openloop power control

innerloop power control

outerloop power control

downlink power balance

involved network element

software release

system performance

technical description