zte umts load adaptive power control feature guide

7/26/2019 ZTE UMTS Load Adaptive Power Control Feature Guide

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Load Adaptive Power Control

Feature Guide


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ZTE Confidential Proprietary 1


Version Date Author Reviewer Notes

V1.00 2013/12/25 WangShaojiang New

2014 ZTE Corporation. All rights reserved.

ZTE CONFIDENTIAL: This document contains proprietary information of ZTE and is not to be disclosed or used

without the prior written permission of ZTE.

Due to update and improvement of ZTE products and technologies, information in this document is subjected to

change without notice.


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TABLE OF CONTENTS

1

Feature Attribute ............................................................................................... 4

2

Overview ............................................................................................................ 4

2.1

Feature Introduction ............................................................................................. 4

2.1.1

Load Adaptive Power Control............................................................................... 4

2.2 License Control .................................................................................................... 5

2.3

Correlation with Other Features ........................................................................... 5

3

Technical Description ....................................................................................... 6

3.1

Load Adaptive Power Control............................................................................... 6

4

Parameters ....................................................................................................... 14

4.1

Load Adaptive Power Control............................................................................. 14

4.1.1

Load Adaptive Power Control Related Switch and Load Estimate Parameters .. 15

4.1.2

Load Adaptive Power Control Related 9-Element Power Control Parameters

(USrvPc) ............................................................................................................ 21

4.1.3

Load Adaptive Power Control Related 9-Element Power Control Parameters

(USrvDivPc) ....................................................................................................... 33

5

Related Counters and Alarms ........................................................................ 38

5.1

Related Counters ............................................................................................... 38

5.2

Related Alarms .................................................................................................. 40

6

Engineering Guide .......................................................................................... 40

6.1

Application Scenario .......................................................................................... 40

6.2

Feature Activation Procedure ............................................................................. 41

6.3

Feature Validation Procedure............................................................................. 48

6.4

Feature Deactivation Procedure ......................................................................... 49

6.5

Network Impact .................................................................................................. 49

7

Abbreviation .................................................................................................... 51

8

Reference Document ....................................................................................... 51


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FIGURES

Figure 3-1 Sketch Map for Obtaining Power Control Parameters When Call Setup ...........10

Figure 6-1 Parameters configuration interface 1 ................................................................42






TABLES

Table 2-1 License Control List ............................................................................................ 5

Table 3-1 RoT Level ..........................................................................................................11

Table 3-2 Uplink Equivalent AMR User Number Level .......................................................13

Table 3-3 DL Load Level ....................................................................................................14

Table 3-4 User Priority .......................................................................................................14

Table 4-1 Load Adaptive Power Control Related Switch and Load Estimate Parameters ..15

Table 4-2 Load Adaptive Power Control Related 9-Element Power Control Parameters

(USrvPc)...............................................................................................................................21

Table 4-3 Load Adaptive Power Control Related 9-Element Power Control Parameters

(USrvDivPc) .........................................................................................................................33

Table 5-1 Counter List .......................................................................................................38


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1 Feature Attribute

RNC Version: [ZXWR RNC V3.13.10.10 / ZXUR 9000 V4.13.10.10]

Node B Version: [ZXSDR V4.12.10.23]

Attribute: [Optional]

Related Network Element:

NE Name Related or Not Special Requirements

UE -

Node B -

RNC

iTC -

MSC -

MGW -

SGSN -

GGSN -

HLR -

: Related, -: Irrelative

2 Overview

2.1 Feature Introduction

2.1.1 Load Adaptive Power Control

There are high load cells in the real network system the load difference of these cells

between busy hour and idle hour is very large. The fixed power control parameters

cannot satisfy simultaneously the requirements of service quality and system capacity

when the load of the cell is changed with time. So the load adaptive power control is

introduced to improve system capacity when the load of the cell is high in busy hour and

protect the service quality when the load of the cell is low during idle hour. At the same


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time, the users with higher priority hope to be served better service quality. In order to

embody the Qos difference among the users with different priority, so the power control

parameters can be configured according to the priority.

2.2 License Control

This feature is controlled by the license, so it should be authorized in OMCR before use

this feature.

Table 2-1 License Control List

Feature ID Feature NameLicense

Control Item

Configured

NE

Sales

Unit

N/A Uplink Capacity

Solution-Load

Adaptive Power

Control

Uplink

Capacity

Solution-Loa

d Adaptive

Power

Control

RNC RNC

2.3 Correlation with Other Features

1. Required Features

Load adaptive power control is to improve the configuration of power control

parameters and it is based on the power control. So the required feature is

ZWF21-04-009 Power Control.

2. Mutually Exclusive Features

None

3. Affected Features

None


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3 Technical Description

3.1 Load Adaptive Power Control

This algorithm can provide better service quality when the cell load is low and decrease

the service quality when the cell load is high, in this way, more online users can be

supported when the load is very high. At the same time, the users with different priorities

can get different service quality.

Firstly, the three cell load levels are defined. They are low Load, medium load and high

load. The three user types based on allocation priority are defined. They are golden-level

user, silver-level user and bronze-level user.

Some power control parameters are designed as 9-element arrays, each element is

relative to cell load and user priority as the following:

Element 1: low load, golden-level user;

Element 2: low load, silver-level user;

Element 3: low load, bronze-level user;

Element 4: medium load, golden-level user;

Element 5: medium load, silver-level user;

Element 6: medium load, bronze-level user;

Element 7: high load, golden-level user;

Element 8: high load, silver-level user;

Element 9: high load, bronze-level user.

Related parameters including:

In the object USrvPc:

Parameter GUI Name Parameter


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Parameter GUI Name

Parameter

Tolerance BLER Period USrvPc.blerAccpPeriod

BLER Target USrvPc.blerTarget

Threshold of Sample Number to Adjust SIR Target

Downward (10ms E-TTI) USrvPc.dwThrSampNumTti10

E-DCH HARQ Power Offset FDD USrvPc.edchHarqPOFdd

Error Transport Block Number Threshold USrvPc.errorThresh

NHR Threshold to Adjust SIR Target Downward

(10ms E-TTI) USrvPc.nhrThrDownTti10

NHR Threshold to Adjust SIR Target Upward (10ms

E-TTI) USrvPc.nhrThrUpTti10


Upward (10ms E-TTI) USrvPc.upThrSampNumTti10

The Number Threshold of Physical Channel BER

Less Than or Equal BER Target USrvPc.qeCntThres

Physical Channel BER Target For Silent Mode USrvPc.qePhyBerTarSil

Uplink SIR Target Down Step Size USrvPc.ulSirTargDnStep

Uplink SIR Target Up Step Size USrvPc.ulSirTargUpStep

Uplink SIR Target Maximum Down Step Size USrvPc.maxSirTargDnStep

Uplink Outer Loop PC SIR Target Adaptive Down

Step Size Switch USrvPc.swchAdaptiveStep

Threshold of HARQ Failure Indication Number to

Adjust SIR Target Upward (10ms E-TTI) USrvPc.thrHarqFailTti10

Threshold of HARQ Failure Indication Number to

Adjust SIR Target Upward (2ms E-TTI) USrvPc.thrHarqFailTti2


Downward (2ms E-TTI) USrvPc.dwThrSampNumTti2

NHR Threshold to Adjust SIR Target Downward (2ms

E-TTI) USrvPc.nhrThrDownTti2

NHR Threshold to Adjust SIR Target Upward (2ms

E-TTI) USrvPc.nhrThrUpTti2


Upward (2ms E-TTI) USrvPc.upThrSampNumTti2

Uplink Outer Loop PC QE Switch For Silent Mode USrvPc.ulOlPcQESwchSil

Uplink SIR Target Maximum Up Step Size USrvPc.maxSirTargUpStep


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Parameter GUI Name

Parameter

SIR Target Rapid Convergence Switch USrvPc.sirRapidConvSwi

Uplink SIR Target Up Step Size for R99 USrvPc.ulSirStep

Uplink SIR Target Up Step Size for HSUPA (2ms

E-TTI) USrvPc.ulSirStepTti2

Uplink SIR Target Up Step Size for HSUPA (10ms

E-TTI) USrvPc.ulSirStepTti10

Target Number of HARQ Retransmission USrvPc.targetRetranNum

The Target Rate of FP HARQ Retransmission

Number Over the Target (2ms E-TTI) USrvPc.fpTargErrorTti2

The Target Rate of FP HARQ Retransmission

Number Over the Target (10ms E-TTI) USrvPc.fpTargErrorTti10

The BER Threshold of Increasing SIR Target in the

Periodic BER-based OLPC Algorithm USrvPc.berTargetUpThres

The BER Threshold of Decreasing SIR Target in the

Periodic BER-based OLPC Algorithm USrvPc.berTargetDnThres

Additional SIR Target Down Period of the SIR Target

Rapid Convergence Function USrvPc.addiSIRDownPeriod

In the object USrvDivPc:


DPCCH Pilot Field Eb/N0 USrvDivPc.dpcchPilotEbN0

DPCH PO1 USrvDivPc.dpchPO1



DPCH Maximum DL Power USrvDivPc.maxDlDpchPwr

Maximum Allowed Uplink DPCH Transmission Power USrvDivPc.maxUlDpchPwr

DPCH Minimum DL Power USrvDivPc.minDlDpchPwr

Uplink Initial SIR Target USrvDivPc.ulInitSIR

Maximum Uplink SIR Target USrvDivPc.ulMaxSIR

Minimum Uplink SIR Target USrvDivPc.ulMinSIR

Initial Value for BLER Based SIR Target USrvDivPc.initBlerSIR

Initial Value for Additional SIR Target USrvDivPc.initSirAdd

Uplink Initial SIR Target (10ms TTI HSUPA) USrvDivPc.ulInitSIRTti10


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Maximum Uplink SIR Target (10ms TTI HSUPA) USrvDivPc.ulMaxSIRTti10

Minimum Uplink SIR Target (10ms TTI HSUPA) USrvDivPc.ulMinSIRTti10

Initial Value for BLER Based SIR Target (10ms TTI

HSUPA) USrvDivPc.initBlerSIRTti10

Initial Value for Additional SIR Target (10ms TTI

HSUPA) USrvDivPc.initSirAddTti10

Uplink Initial SIR Target (2ms TTI HSUPA) USrvDivPc.ulInitSIRTti2

Maximum Uplink SIR Target (2ms TTI HSUPA) USrvDivPc.ulMaxSIRTti2

Minimum Uplink SIR Target (2ms TTI HSUPA) USrvDivPc.ulMinSIRTti2

Initial Value for BLER Based SIR Target (2ms TTIHSUPA) USrvDivPc.initBlerSIRTti2

Initial Value for Additional SIR Target (2ms TTI

HSUPA) USrvDivPc.initSirAddTti2

About the details of power control parameters above mentioned, please refer to ZTE

UMTS Power Control Feature Guide, ZTE UMTS HSUPA Introduction Feature Guide,

and ZTE UMTS Power Control Algorithm Enhancement Feature Guide .

When the service is accessed or reconfigured, the power control parameters are

obtained according to the following principle.

1. When the switch UCelInfoFDD.blerLoadSwitch is on, the uplink and downlink

power control parameters are determined from the 9-element parameters based on

the uplink real cell load and downlink real cell load respectively. Otherwise, the

power control parameters are determined based on the default cell load level

indicated by UCelInfoFDD.defaultLoadLevel.

2. When the switch URncInfo.blerArpSwitchis on, the power control parameters are

determined based on the user priority indicated by ARP (Allocation/Retention

priority) .If the switch is off or the ARP information cannot be obtained, the

parameters are determined based on user priority indicated by the default ARP

configured by URncInfo.defaultArpSeg.


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When the switch UCelInfoFDD.blerLoadSwitch is on and the switch

URncInfo.blerArpSwitchis on, the power control parameters for the new user are

obtained as following figure.

Figure 3-1 Sketch Map for Obtaining Power Control Parameters When Call Setup

Call Setup

Low Load Level

Golden Silver Bronze Golden Silver Bronze Golden Silver Bronze

Medium Load Level High Load Level

Take

element 1

of the 9-

element

parameter

Take

element 2

of the 9-

element

parameter

Take

element 3

of the 9-

element

parameter

Take

element 4

of the 9-

element

parameter

Take

element 5

of the 9-

element

parameter

Take

element 6

of the 9-

element

parameter

Take

element 7

of the 9-

element

parameter

Take

element 8

of the 9-

element

parameter

Take

element 9

of the 9-

element

parameter

Load Level Estimate

User Priority Identification

The uplink load level, the downlink load level of the cell, and the ARP segment of the

user are determined as the following:

1. The uplink load level of the cell

The uplink load level of the cell is obtained based on RoT and equivalent AMR user

number. And ZTE RNC chooses the lower level between the RoT level and uplink

equivalent AMR user number level as uplink load level.

Where,

i. RoT level is determined as following method:

ZTE RNC will record the common measurement result of RTWP, and filter the

RoT according to the following formula:

RoT(t)= * RoTreport + (1-)*RoT(t-1) (3.1-1)

Where,


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is the filter factor, and obtained from URncInfo.loadFilterCoeff.

RoTreport is the report of the current RTWP common measurement. The

formula is: RoT(dB) = RTWP (dBm) - Background noise (dBm).

RoT(t-1) is the filter result last time.

RoT(t) is the filter result this time.

The RoT level is determined through making a comparison between the filter

result RoT(t) and the related threshold as following table:

Table 3-1 RoT Level

RoT Level RoT

Level 1: Low RoT level

RoT < UCelInfoFDD.lowRotThreshold

Level 2: Medium RoT level

UCelInfoFDD.lowRotThreshold = UCelInfoFDD.highRotThreshold

ii. Uplink equivalent AMR user number level is determined as following method:

The load factor of single service is calculated as:

(3.1-2)

Firstly, RNC will calculate the load factor of the NB-AMR service (LAmr) and the

load factor of service (i) (Li) according to the formula (3.1-2), and then

calculate the equivalent AMR user number of the service (i) according to the

formula (3.1-3):

(3.1-3)

Where,

a) is load factor of the service (i), and is the load factor of the

NB-AMR service.


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b) Eb/No is the uplink service quality factor. It is obtained from the

parameter USubSrv.ulEbN0Pc for the DCH and non-schedule E-DCH

service, and it is obtained from the parameter USubSrv.sEdchEbN0Pc for

the schedule E-DCH service. The unit of USubSrv.ulEbN0Pc and

USubSrv.sEdchEbN0Pc is dB, so they will be transferred through the

formula 10^(USubSrv.ulEbN0Pc/10) and

10^(USubSrv.sEdchEbN0Pc/10) in the calculation.

c) R: it is the target rate for DCH and non-schedule E-DCH services, it is

GBR for the schedule E-DCH services, it is NBR indicated by

UCelInfoFDD.rsrvdBitRate for the interactive or background E-DCH

services.

d) W is 3.84Mbps.

The single signaling will also be calculated the equivalent AMR user number

according to the rules above-mentioned.

And for avoiding the influence to the power control parameters caused by the

fluctuating of equivalent AMR user number, the equivalent AMR user number

will be filtered as the following formula:

UserNum(n) = * UserNumSample + (1-)*UserNum(n-1) (3.1-4)

Where,

a) is the filter factor , and is obtained form URncInfo.userNumFilterCoeff.

b) UserNumSample is the current equivalent AMR number.

c) UserNum(n-1) is the filter result last time.

d) UserNum(n) is the filter result this time.

The equivalent AMR user number level is determined through making a

comparison between the filter result UserNum(n) and the related threshold as

following table:


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Table 3-2 Uplink Equivalent AMR User Number Level

Equivalent AMR User Number

Level

UserNum

Level 1: Low equivalent AMR user

number level

UserNum Managed

Element->UMTS Logical Function Configuration->Extended Info of RNC] interface and

set the parameter The Switch for ARP based BLER Function, Default ARP Segment,

ARP Threshold of Golden Subscriber Used in Power Control,ARP Threshold of Bronze

Subscriber Used in Power Control, Load Filter Coefficient, User Number Filter

Coefficient, as shown inFigure 6-1


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Figure 6-1 Parameters configuration interface 1

In the configuration resource tree window, open the [Modify Area->Managed Element->

UMTS Logical Function Configuration->UTRAN Cell-> Extended Info of UTRAN Cell]

interface and set the parameterThe Switch for Load based BLER Function,Default

Load Level, Low RoT Level Threshold, High RoT Level Threshold, Uplink Low

Equivalent AMR User Number Level Threshold, Uplink High Equivalent AMR User

Number Level Threshold, Downlink Low Load Level Threshold Used in Load Based

Power Control Parameter Configuration,Downlink High Load Level Threshold Used

in Load Based Power Control Parameter Configuration, as shown inFigure 6-2


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UMTS Logical Function Configuration->Service Function-> Service Basic Configuration]

interface and set the parameterUplink DCH or non-Scheduling E-DCH Traffic Eb/N0

used in Uplink Equivalent AMR User Number Calculation Algorithm for Power Control

(dB),Scheduling E-DCH Traffic Eb/N0 used in Uplink Equivalent AMR User Number

Calculation Algorithm for Power Control, as shown inFigure 6-3


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UMTS Logical Function Configuration->UTRAN Cell-> Extended Info of UTRAN Cell]

interface and set the parameterReserved Bit Rate for I&B Scheduling E-DCH Traffic,

as shown inFigure 6-4


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UMTS Logical Function Configuration->Service Configuration-> Service Function->

Power Control Profile Related to Service-> Power Control Related to Service] interface

and set the parameterUplink SIR Target Up Step Size,Uplink SIR Target Down Step

Size,Uplink SIR Target Maximum Down Step Size,Uplink SIR Target Maximum Up

Step Size,BLER Target, Error Transport Block Number Threshold,Tolerance BLER

Period, Threshold of HARQ Failure Indication Number to Adjust SIR Target Upward

(10ms E-TTI), Threshold of HARQ Failure Indication Number to Adjust SIR Target

Upward (2ms E-TTI),NHR Threshold to Adjust SIR Target Downward (10ms E-TTI),

NHR Threshold to Adjust SIR Target Upward (10ms E-TTI),NHR Threshold to Adjust

SIR Target Downward (2ms E-TTI),NHR Threshold to Adjust SIR Target Upward (2ms

E-TTI), Threshold of Sample Number to Adjust SIR Target Upward (10ms E-TTI) ,

Threshold of Sample Number to Adjust SIR Target Downward (10ms E-TTI),E-DCH

HARQ Power Offset FDD,The Number Threshold of Physical Channel BER Less Than

or Equal BER Target,Physical Channel BER Target For Silent Mode,Uplink Outer

Loop PC SIR Target Adaptive Down Step Size Switch,Threshold of Sample Number to

Adjust SIR Target Downward (2ms E-TTI),Threshold of Sample Number to Adjust SIR

Target Upward (2ms E-TTI),Uplink Outer Loop PC QE Switch For Silent Mode ,SIR


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Target Rapid Convergence Switch,Uplink SIR Target Up Step Size for R99,Uplink

SIR Target Up Step Size for HSUPA (2ms E-TTI),Uplink SIR Target Up Step Size for

HSUPA (10ms E-TTI),Target Number of HARQ Retransmission,The Target Rate of

FP HARQ Retransmission Number Over the Target (2ms E-TTI),The Target Rate of

FP HARQ Retransmission Number Over the Target (10ms E-TTI),The BER Threshold

of Increasing SIR Target in the Periodic BER-based OLPC Algorithm , The BER

Threshold of Decreasing SIR Target in the Periodic BER-based OLPC Algorithm ,

Additional SIR Target Down Period of the SIR Target Rapid Convergence Function, as

shown inFigure 6-5



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UMTS Logical Function Configuration->Service Configuration-> Service Function->

Power Control Profile Related to Service-> Power Control Related to Service-> Power

Control Related to Service and Diversity Mode] interface and set the parameterDPCCH

Pilot Field Eb/N0, DPCH PO1, DPCH PO2, DPCH PO3, DPCH Maximum DLPower, Maximum Allowed Uplink DPCH Transmission Power, DPCH Minimum DL

Power,Uplink Initial SIR Target,Maximum Uplink SIR Target,Minimum Uplink SIR

Target, Initial Value for BLER Based SIR Target, Initial Value for Additional SIR

Target, Uplink Initial SIR Target (10ms TTI HSUPA), Maximum Uplink SIR Target

(10ms TTI HSUPA),Minimum Uplink SIR Target (10ms TTI HSUPA),Initial Value for

BLER Based SIR Target (10ms TTI HSUPA), Initial Value for Additional SIR Target

(10ms TTI HSUPA),Uplink Initial SIR Target (2ms TTI HSUPA),Maximum Uplink SIR

Target (2ms TTI HSUPA),Minimum Uplink SIR Target (2ms TTI HSUPA),Initial Value


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for BLER Based SIR Target (2ms TTI HSUPA),Initial Value for Additional SIR Target

(2ms TTI HSUPA), as shown inFigure 6-6


6.3 Feature Validation Procedure

None


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6.4 Feature Deactivation Procedure

None

6.5 Network Impact

1. Impact of Equipment Performance

After the feature is activated, the cell load level will be calculated all the time, it

contains RoT, uplink equivalent AMR user number and downlink load, so the CPU

load of the RNC will be increased. The CPU load of CMP board will be increased

about 0.5%, and the CPU load of DMP board will be increased about 1%.

2. Impact of Network KPI

i. Load adaptive power control

Activating this feature, the advantage is:

The feature is suit for the network that the load is changed with time severelyor some cell load is high. The different values for power control parameters are

configured for different load level, the power control parameters with low

requirement are used by the high load cell, and it will improve the system

capacity and the basic KPI performance of the network, such as increasing the

ratio of successful call setup, decreasing the call drop ratio. And the power

control parameters with high requirement are used by the low load cell, and it

will improve the user experience.

In the test scene, when the feature the load adaptive power controland the

feature power control algorithm enhancementare activated simultaneously,

the KPI performance is following. About the feature power control algorithm

enhancement, please refer to the ZTE UMTS Power Control Algorithm

Enhancement Feature Guide.

UL load per UL throughput is reduced by 6%~17%.

HSUPA throughput in high load condition is increased about 7%~11%.


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Call drop ratio of the PS service is reduced by 7%~20%.

Other KPIs have no affection.

The disadvantage is:

When the cell load is high load level, the service quality is decreased

comparing with the service quality when the cell load is low load level.

ii. ARP adaptive power control

Activating this feature, the advantage is:

The function is suit for the network that has the subscribers with different

priorities, the subscribers with high priority use the power control parameters

for good service quality, and the subscribers with low priority use the power

control parameters for poor service quality. The service quality of the

subscriber with high priority can be improved.


The service quality of the subscriber with low priority will be decreased.

iii. The load adaptive power control and the ARP adaptive power control are

activated at the same time.

The advantage is:

If there are users with different priority in the network, and the service quality of

the subscribers has been decreased after the load adaptive power control

function has been used. Activating the ARP adaptive power control functioncan make the different priority users with different service quality, and the

service quality of the user with higher priority still can be good.


None.


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7 AbbreviationAbbreviations Full Characteristics

AMR Adaptive Multi Rate

ARP Allocation/Retention Priority

BLER Block Error Rate

DCH Dedicated Channel

DL Downlink

E-DCH Enhanced Dedicated Transport Channel

GBR Guaranteed Bit Rate

HS-DSCH High Speed Downlink Shared Channel

NAMR Narrow Band Adaptive Multi-Rate

OMCR Operations & Maintenance Center-radio

QoS Quality of Service

RNC Radio Network Controller

RTWP Received Total Wide Band Power

RoT Rise over Thermal

UE User Equipment

UL Uplink

UMTS Universal Mobile Telecommunication System

WCDMA Wideband Code Division Multiple Access

8 Reference Document

[1] ZXUR 9000 UMTS (V4.13.10.10) Radio Network Controller Radio Parameter

Reference

[2] ZXWR RNC (V3.13.10.10) Radio Network Controller Radio Parameter Reference

[3] ZXUR 9000 UMTS (V4.13.10.10) Radio Network Controller Performance Counter

Reference

[4] ZXWR RNC (V3.13.10.10) Radio Network Controller Performance Counter Reference


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[5] ZTE UMTS Power Control Feature Guide

[6] ZTE UMTS HSUPA Introduction Feature Guide

[7] ZTE UMTS Power Control Algorithm Enhancement Feature Guide

zte umts load adaptive power control feature guide

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