owa200004 wcdma radio resource management issue 1.1

www.huawei.com

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

WCDMA Radio Resource Management (RRM)


Contents

1. Introduction to RRM

2. Channel Configuration

3. Power Control

4. Mobility Management

5. AMR Mode Control


Introduction to RRM RRM: Radio Resource Management

RRM is responsible for supplying optimum coverage, offering the maximum planned capacity, guaranteeing the required quality of service (QoS) and ensuring efficient use of physical and transport resources.

Power is the ultimate radio resource. The best way to utilize the radio resource is to control the power consumption strictly.

Increasing the transmission power of a certain user can improve his QoS.

However, due to the self-interference, the increasing would result in more interference on other users and consequently reduce the receiving QoS.


Procedure of RRM

Fundamental procedure of radio resource

management

Measurement control

measurement

UE, NodeB, RNC

Measurement report

Judgment

Execution


Contents



3. Power Control


5. AMR Mode Control


Contents


2.1 Fundamental channel configuration

2.2 Dynamic channel configuration


Fundamental Channel Configuration Objective: mapping the RAB QoS features requested to

distribute appropriate channel

QoS requested by CN Traffic Classes

Conversational

Streaming

Interactive

Background

Rate demand

Quality demand (BLER)

Time delay


QoS Mapping

DPDCH DPCCH

RAB

RB RB

DTCH DTCH DCCH

TrCHTrCH TrCH

CCTrCH

RLC entity

Mac-d Mac-c

Coding& RM&Mux

Radio Bearers

RLC Sublayer

Logical Channels

MAC Sublayer

Transport Channels

Physical Layer

DTCH

．．．

Coding& RM&Mux

TrCH


RB and RLC Parameter Configuration RB parameters

RB number

RLC parameters

Different RLC transfer modes

transparent mode (TM)

Unacknowledged mode (UM)

Acknowledged mode (AM)

Different logic channel parameters


MAC Parameter Configuration MAC parameters

The mapping/multiplexing relation between logic channel and transport channel

Different types and parameters of transport channel Dedicated channel

Common channel

Different configurations of MAC entity MAC-d/MAC-c

Priority configuration of MAC sub layer

TFCS configuration


PHY Parameter Configuration PHY parameters

Mapping relation from transport channel to physical channel Channel Coding scheme

Convolutional code Turbo code Non

Interleaving length Rate matching attribute Spreading factor (SF) Power offset Other physical channel parameters, such as diversity mode, etc.


Contents


2.1 Fundamental channel configuration

2.2 Dynamic channel configuration


DCCC: Dynamic Channel Configuration Control

Object of DCCC: Best Effort (BE) service

Features of BE service

rate of service source changes largely

Less demand on time delay

More demand on bit error rate


Dynamic Channel ConfigurationDynamic Channel Configuration

MAC-d

DL Transport Channel Traffic Volume

Threshold

Configuration in L2

RLC

Signaling bearer

DCH1

RLC

TFC SelectTFC Select

DCH2

Channel SwitchingChannel Switching

DCCH DTCH


Decision of DCCC

Decision of DCCC

Measurement report on traffic volume of RLC Buffer

Decide whether to change the bandwidth used by UE

dynamically based on the measurement result.

Consider whether there is limitation on air interface

during the decision of reconfiguration.

The uplink & downlink DCCC decisions are the same, but are executed respectively.


Effect of DCCC

System capacity

Traditional channel configuration

Rate of service source

DCCC

Achieve “bandwidth on demand”

Time

rate


Contents



3. Power Control


5. AMR Mode Control

Near-far effect in CDMA

A B

P()

P()

P()

P()

Received power from user A

P()

Despreading

Transmission power of user A

Received power by NodeB

The user A can communicate successfully

Received power from user B

Transmission power of user A

The user B is submerged because of strong interference

from user A

user A

user B


Classification of Power Control Power Control

Uplink power control Open loop power control

Closed loop power control

– Inner loop power control

– Outer loop power control

Downlink power control Open loop power control

Closed loop power control

– Inner loop power control

– Outer loop power control


Open Loop Power Control for DPCH

Accurately calculate initial

transmitting power of

inner loop needed to

lessen the time of

convergence

Reduce the impact on

system load

Convergence of inner loop power control

time

power

time

power


NodeB UERACH

BCH: CPICH channel power UL interference level

Open Loop Power Control for PRACH


Uplink Closed Loop Power Control

NodeB UE

Transmit TPC

Measure&compare

SIR of received signal

Inner loop

Set SIRtar

1500Hz


BLER--SIR

SIR

BLER

Different curves correspond with different multi-path environment


Uplink Closed Loop Power Control

NodeB UE

Transmit TPC

Measure&compare

SIR of received signal

Inner loop

Set SIRtar

Traffic data with steady BLER can be acquired

Measure BLER of transport channel

Outer loop

RNC

Measure&compare BLER of received data

Set BLERtar

10-100Hz


Downlink Power Control

NodeB

Set SIRtar

Transmit TPC

Measure and compare SIR

Measure and compare BLER

Outer loop

Inner loop UE physical layer

UE Layer 3

Downlink inner loop and outer loop power control

10-100Hz1500Hz


Contents



3. Power Control


5. AMR Mode Control


UE Working Modes and states

Idle mode

Connected mode

Cell_DCH

Cell_FACH

Cell_PCH

URA_PCH


UE Working Modes and states Idle Mode

The UE has no relation to UTRAN, only to CN. For data transfer, a signalling connection has to be established

UE camps on a cell It enables the UE to receive system information from the PLMN UE can establish an RRC connection, it can do this by initially

accessing the network on the control channel of the cell on which it is camped

UE can receive "paging" message from PCH

The idle mode tasks can be subdivided into three processes PLMN selection and reselection Cell selection and reselection Location registration



Connected Mode – Cell_DCH In active state Communicating via its dedicated channels UTRAN knows the cell in which UE is located.



Connected Mode - Cell-FACH

In active state

Few data to be transmitted both in uplink and in

downlink. There is no need to allocate dedicated

channel for this UE

Downlink uses FACH and uplink uses RACH

UE need to monitor the FACH for its relative

information

UTRAN knows the cell in which UE is located



Connected Mode – Cell_PCH No data to be transmitted or received DRX (discontinuous reception) monitor PICH, to recei

ve its paging lower the power consumption of UE UTRAN knows the cell in which UE is located UTRAN have to update cell information of UE when U

E roams to another cell



Connected Mode – URA_PCH No data to be transmitted or received

DRX monitor PICH

UTRAN only knows the URA in which UE is located

UTRAN update UE information only after UE has roamed to other URA (UE report own new URA by URA update procedure)

A better way to lower the resource occupancy


UE states switching

CELL_DCH CELL_FACH

CELL_PCHURA_PCH

IDLE

DEAD - Scanning networks (PLMN)- ”Camp on” cell

- Monitor paging channel- cell re-selection

- Dedicated Channel- Radio bearers Transmission Services

- upper layer Signalingtrigger (CN)

- Reduce action ， DTX ， and save power

RRC connection


UE move

Target BSSource BS

time

Data UE received/

sent

“GAP” of communication

Hard handover


Soft Handover

UE move

Target BSSource BS

time

Data UE received

/ sentNo “GAP” of communication


The Basic Concept of SHO

Active Set

Including all cells currently participating in a SHO

connection of a UE

Monitored Set

Including all cells being continuously monitored by the UE

and which are not current included in its active set

Detected set

Including the cells the UE has detected but are neither in

the active set nor in the monitored set


Three Steps of Handover

Decision

Execute

Measurement


The Basic Concepts of Measurement The measurement values of Handover

Intra-frequency and inter-frequency: CPICH RSCP 、 CPICH Ec/N0 、 Path loss Inter-frequency ： CPICH RSCP 、 CPICH Ec/N0 Inter-system ： GSM Carrier RSSI ， BSIC Identification ， BSIC Reconfirmation

The reporting methods of measurement Periodic reporting Event reporting

The events of reporting Intra-frequency events ： 1A,1B,1C,1D,1F Inter-frequency events ： 2D,2F,2B,2C Inter-system events ： 3A,3C Others ： 6G,6F


Reporting Criterion

Reporting Criterion Decision formula: for example, 1A event : 1.Path Loss

2.Other measurement quantity ：

Relative threshold, Absolute threshold, Hysteresis, Time to trigger, CIO

)2/(10)1()/1(/11010 111

aaBest

N

iiNewNew HRLogMWMLogWCIOLogM

A

)2/(10)1(1010 111

aaBest

N

iiNewNew HRLogMWMLogWCIOLogM

A


Soft Handover

△ T △ T △ T

1A Event 1B Event Nottri ggered

Report i ngRange

Hyst

C

B

ACPI CHEc/ No


Application of Hard Handover in 3G Intra-frequency hard handover

When inter-RNC SHO can’t be executed or is not allowed

Inter-frequency hard handover Needed in certain areas due to network planning

Load balance between frequencies

Inter-RAT handover 2G-3G smooth evolution

The finite coverage range of initial phase of 3G


Compressed Mode

Objective of compressed mode: for UE to realize measurement and synchronization to target cell when inter-frequency handover and inter-system handover is required


Classification of Compressed Mode Downlink compressed mode

To create time for UE’s measurement and synchronization.

2 optional schemes -- SF/2,higher layer scheduling

Uplink compressed mode

To avoid the interference on its own downlink measurement

and synchronization when UE is measuring certain target

frequency or RAT

2 optional schemes -- SF/2, higher layer scheduling


SRNS(C) Relocation

Advantage of SRNS relocation Reducing data flow on Iur interface

Improving the system’s adaptability.

Reducing the time delay

Problem of SRNS Relocation: a large amount of signaling is needed to interact.

CN

SRNS DRNS

CN

RNS SRNS


Contents



3. Power Control


5. AMR Mode Control


AMR CodingAMR Coding

WCDMA system uses Adaptive Multi-Rate (AMR) speech

code, which is linear prediction coding

Rate no.

Sub-flow 1 block size

（bit）


（bit）


（bit）

Combination block size

（bit）

rate（kbps）

0 0 0 0 0 No data

1 39 0 0 39 SID

2 42 53 0 95 4.75

3 49 54 0 103 5.15

4 55 63 0 118 5.9

5 58 76 0 134 6.7

6 61 87 0 148 7.4

7 75 84 0 159 7.95

8 65 99 40 204 10.2

9 81 103 60 244 12.2


Features of AMR speech: MOS-CIR


AMR Mode Control

AMR mode control is to weigh the load level, and:

Reduce AMR speech rate on heavy load condition, thus

reduce the system load and improve speech quality

relatively

Increase AMR speech rate on light load condition, thus

improve QoS

Reducing of AMR speech rate can widen the uplink

coverage effectively

The AMR speech mode control can be done every 20ms

Thank youwww.huawei.com

owa200004 wcdma radio resource management issue 1.1

Documents