03 wr bt1004 e01_1 wcdma key technology-80

WCDMA Key Technologies

ZTE University

Objectives

At the end of this course, you will be able to: Master key technologies of WCDMA Master characteristic of WCDMA system capacity

Content

WCDMA Key Technologies Power Control Handover Control Admission Control Load Control Code Resource Allocation RAKE Receiver

WCDMA Capacity Features

Power Control

CDMA is not a new technology Power control is a key technology of CDMA

system Power control is the key path for launching the

large scale CDMA commercial network

CDMA is a typical self-interference system, thus the chief CDMA is a typical self-interference system, thus the chief

principle is that any potential surplus transmitted power for principle is that any potential surplus transmitted power for

service must be controlled.service must be controlled.

CDMA is a typical self-interference system, thus the chief CDMA is a typical self-interference system, thus the chief

principle is that any potential surplus transmitted power for principle is that any potential surplus transmitted power for

service must be controlled.service must be controlled.

Why Power Control?

All CDMA users occupy the same frequency spectrum at the same time! Frequency and time are not used as discriminators.

CDMA operates by using codes to discriminate between users.

CDMA interference comes mainly from nearby users

Each user is a small voice in a roaring crowd -- but with a uniquely recoverable code.

To achieve acceptable service quality, the transmit power of all users must be

tightly controlled so that their signals reach the base station with the same

signal strength and the absolute minimum power level demanded to avoid

the Near-Far Effect.

Power

f

Overpowered by strong signalsBlock the whole cell

Near-Far Effect

Each terminal is an interference Each terminal is an interference

source to the others. The Near-far source to the others. The Near-far

effect will impact the capacity effect will impact the capacity

tremendouslytremendously

Each terminal is an interference Each terminal is an interference

source to the others. The Near-far source to the others. The Near-far

effect will impact the capacity effect will impact the capacity

tremendouslytremendously

Power

f

Power control will reduce the Power control will reduce the

cross interference significantly cross interference significantly

and improve the total capacityand improve the total capacity

Power control will reduce the Power control will reduce the

cross interference significantly cross interference significantly

and improve the total capacityand improve the total capacity

Power

f

Power control

• Overcome near-far effect and compensate signal fading

• Reduce multi-access interference and guarantee cell capacity

• Extend battery life

Downlink Power Control

UE transmitted signal

Power control command (TPC)

Uplink Power Control

Cell transmitted power

Power control command (TPC)

Purpose of Power Control

Category of Power control

UE

RNC

Node B

Open loop power control （ no feedback）

Close loop power control （ feedback）

UE Node B

RNCOuter-loop

Inner-loop

Open LoopMeasure the channel interference condition and adjust the initial transmitted power

Close Loop － Inner LoopMeasure the SIR (Signaling to Interference Ratio), compare with the target SIR value, and then send power control instruction to UE.

The frequency of WCDMA inner loop power control is 1500Hz.If measured SIR>target SIR, decrease the UE transmitted power.If measured SIR <target SIR, increase the UE transmitted power.

Close Loop － Inner LoopMeasure the SIR (Signaling to Interference Ratio), compare with the target SIR value, and then send power control instruction to UE.

The frequency of WCDMA inner loop power control is 1500Hz.If measured SIR>target SIR, decrease the UE transmitted power.If measured SIR <target SIR, increase the UE transmitted power.

Close Loop － Outer LoopMeasure the BLER (Block Error Rate), and adjust the target SIR.

The frequency of WCDMA outer loop power control is 10~100Hz. If measured BLER>target BLER, decrease the target SIR value. If measured BLER<target BLER, increase the target SIR value.

Close Loop － Outer LoopMeasure the BLER (Block Error Rate), and adjust the target SIR.

The frequency of WCDMA outer loop power control is 10~100Hz. If measured BLER>target BLER, decrease the target SIR value. If measured BLER<target BLER, increase the target SIR value.

Category of Power Control

Open Loop Power Control

General principals of open loop power control Open loop power control is applied to estimate the initial

transmitted power for a new radio link. P-CPICH signal is used in Downlink Open Loop Power

Control, which is measured by UE to estimate the initial transmitted power.

The following factors will also be considered, such as service QoS and data rate, Eb/No requirements of establishing service, current downlink total Transmitted Power and interference from neighbor cell etc.

Try to get the equal receiving Try to get the equal receiving

Eb (Energy per bit) of each Eb (Energy per bit) of each

UE at Node BUE at Node B

Try to get the equal receiving Try to get the equal receiving

Eb (Energy per bit) of each Eb (Energy per bit) of each

UE at Node BUE at Node B

NodeB UE

TPC instruction

Measure receiving SIR and

compare to target SIR

Inner loop

Set SIRtar

1500Hz1500Hz1500Hz1500Hz

Each radio link has Each radio link has

its own control its own control

circlecircle

Each radio link has Each radio link has

its own control its own control

circlecircle

Close Loop – Inner Loop Power Control


General principals of inner loop power control The receiver compares the SIR value of received signal with target SIR,

and then sends back TPC instruction. According to the instruction, the sender will decide to increase/decrease the transmitted power.

The adjusted rang=TPC_cmd×TPC_STEP_SIZE

Inner loop power control is required for the following channels： DPCH, PDSCH, PCPCH

Inner loop power control is not required for the following channels ： P-CPICH(S-CPICH), P-CCPCH(S-CCPCH), PRACH etc.

NodeB UE

TPC instruction

Inner loop

Set SIRtar

Get data flow Get data flow

with stable BLERwith stable BLER

Get data flow Get data flow

with stable BLERwith stable BLER

Measure BLER Measure BLER

of TRCHof TRCH

Measure BLER Measure BLER

of TRCHof TRCH

Outer Loop

RNC

Measure receiving BLER and compare to

target BLER

Set BLERtar

10-100Hz

Measure receiving SIR and

compare to target SIR


Close Loop – Outer Loop Power Control

Outer Loop Power Control algorithm Employ the inner loop power control to keep SIR close to target

SIR. Measure the quality of service, including target BLER, CRC

indicator and SIR Error, then set the value of SIR_Target. Tune the target SIR with pre-defined step as the adjustment

parameter for inner loop power control to keep the service in good quality in time-varying wireless propagation environment.

The uplink open loop power control algorithm is executed in the RNC while the downlink one is executed in UE.

The Effect of Power Control

The purpose of DL power control: Saving power resource of NodeB. Reducing interference to other NodeB.

The purpose of UL power control: Overcoming Near-Far effect. Extending UE battery life.

WCDMA system capacity depends on the effect of power control

Content



What’s ？ When UE is moving from the coverage area of one site to another,

or the quality of service is declined by external interference during a service, the service must be handed over to an idle channel for sustaining the service.

Handover is used to guarantee the continuity of service

Handover is a key technology for mobile networking

Category of Handover

Intra-RNC, inter-Node B Inter-RNC

Soft handover (SHO)

Same Node B, Inter-sector

Softer handover

Intra-frequency Inter-frequency Inter-system (3G&2G) Inter-mode (FDD&TDD)

Hard handover (HHO)

WCDMA system support

multiple handover technology

Handover Demonstration

Soft

Handover

Hard Handover

A

B

C

A

B

C

A

B

C

A

B

C

A

B

C

A

B

C

Soft Handover/Softer Handover

Soft Handover

Soft-Softer Handover

Softer Handover

Hard Handover

During the hard handover procedure, all the old radio links with the UE are abandoned before new ones are established, so there must be service interruption during the HHO.

Hard handover may occur in the following main cases

When the UE is handed over to another UTRAN carrier, or another technology mode.

When soft handover is not permitted (if O&M constraint)

Hard Handover

Node B

SRNCRNC or BSC

CN

Node B or BTS

Soft/Softer Handover

The soft/softer handover allows to migrate from one cell to another without service interruption or without deleting all old radio links.

UE can connecte to more than one cell simultaneously and take benefit from the macro-diversity.

Soft Handover Softer Handover

CN CN

Iur

The two Node Bs may belong to the

same RNC

The two Node Bs may belong to the Same RNC


SRNC DRNC

CN

Node B

SRNC

CN


Node B

CN

WCDMA General Handover Procedures---- “Handover Trilogy” Measurement Control

UTRAN demands the UE to start measurement through issuing a measurement control message.

Handover decision UTRAN makes the decision based on the measurement

reports from UE. The implementation of handover decision is various for different vendors. It impacts on the system performance critically.

Handover execution UTRAN and UE execute different handover procedure

according to the handover command .

General Procedure of Handover Control (I)

Measuring

The measurement objects are decided by RNC. Usually, either Ec/N0 or

RSCP (Received Signal Code Power) of P-CPICH channel is used for

handover decision.

ZTE RNC adopts Ec/N0 measurement, because Ec/N0 embodies both

the received signal strength and the interference. The relation of Ec/N0

and RSCP is shown as follows:

Ec/N0 ＝ RSCP/RSSI

In the above equation ， RSSI （ Received Signal Strength Indicator ） is

measured within the bandwidth of associated channels

General Procedure of Handover Control (II)

Reporting Period report triggered handover

Base on the filtered measurement result Event report triggered handover

Base on the event

Soft Handover

Hard Handover

Period

Event

Measurement result filtered in

UE

Event decided in RNC

Handover decided in RNCMeasurement result filtered in UE Event decided in UE

Handover decided in RNC

General Procedure of Handover Control (III)

Handover algorithm All the handover algorithms including soft handover,

hard handover and so on are implemented on the event decision made according to the measurement reports.

Events defined in 3GPP specifications Intra-frequency events ： 1A~1F Inter-frequency events ： 2A~2F Inter-RAT events ： 3A~3D

Note: RAT is short for “Radio Access Technology”, e.g. WCDMA&GSM

Concepts Related to Handover

Active Set: A set of cells that have established radio links with a

certain mobile station. User information is sent from all these cells.

Monitored Set: A set of cells that are not in the active set but are

monitored according to the list of adjacent cells assigned by the UTRAN.

Detected Set: A set of cells that are neither in the active set nor in the

monitor set.

Soft handover process

Measurement RNC sends a measurement control message to UE. UE should perform measurement as required and report the measurement

result. Generally, the measured parameter is the common pilot’s Ec/No.

Decision RNC stores data of different cells according to the measurement results. RNC makes preliminary decision according to the event decision method. e.g.

When the event is reported and the target cell is acceptable, send an active set update command to add/delete the cell into/from the active set.

Execution The RNC sends an active set update command to UE and UE starts

handover.

Soft handover events

Event Description

1A Quality of target cell improves, entering a report range of relatively activating set quality

1B Quality of target cell decreases, depart from a report range of relatively activating set quality

1C The quality of a non-activated set cell is better than that of a certain activated set cell

1D Best cell generates change

1E Quality of target cell improves, better than an absolute threshold

1F Quality of target cell decreases, worse than an absolute threshold

An Example of SHO Procedure

Pilot Ec/Io of cell 1

time

PilotEc/Io

Connect to cell1 Event 1A Event 1C Event 1B （ add cell2）（ replace cell1 with cell 3）（ remove cell3）



⊿t ⊿t ⊿t

Example of soft handoverUE Target Node B Source Node B RNC

RRC: Measurement Report(Event 1a) (From Source Node B to RNC)

NBAP: Radio Link Setup Request

NBAP: Radio Link Setup Response

Executing handoverjudgement andadding a radio linkin Target Node B

Start to receive

Distributing transmission resources on Iub interface

Start to send

RRC: Active Set Update(E1a) (From Source Node B to UE)

RRC: Active Set Update Complete (From Source & Target Node B to RNC

simutaneously)

UE connects to Source Node B and Target Node B simutaneously

RNS Relocation

RNS relocation can : Reduce the Iur traffic significantly Enhance the system adaptability

Core NetworkCore Network

Serving RNS

Target RNS

Serviing RNS

Target RNS

Iu Iu

Iur

RNSRadio Network Sub-system

Hard Handover

Hard handover measurement is much more complex for UE than soft handover measurement.

Inter-frequency hard handover requires UE to measure the signal of other frequencies.

WCDMA employs compressed mode technology to support inter-frequency measurement.

Content



Admission Control

The admission control is employed to admit the access of incoming call. Its general principal is based on the availability and utilization of the system resources.

If the system has enough resources such as load margin, code, and channel element etc. the admission control will accept the call and allocate resources to it.

Purpose of Admission Control

When user initiates a call , the admission control should implement admission or rejection for this service according to the resource situation.

The admission control will sustain the system stability firstly and try the best to satisfy the new calling service’s QoS request, such as service rate, quality (SIR or BER), and delay etc. basing on the radio measurement.

Admission control is the only access entry for the incoming services, its strategy will directly effect the cell capacity and stability, e.g. call loss rate, call drop rate.

Admission Control in Uplink

Itotal_old+ΔI >Ithreshold

The current RTWP (Received Total Wide Power) value of cell, which is reported by Node B

AccessThreshold

Interference capacityService priorityReserved capacity for handover

Iown-cell

0~N

Iother-cell

The forecasted interference including the delta interference brought by the incoming service is calculated by the admission algorithm, and its result depends on the QoS and transmission propagation environment

Admission Control in Downlink

Ptotal_old+△P>=Pthreshold Access Threshold

The forecasted TCP value including delta power required for the incoming service is calculated by the admission algorithm, and its result depends on the QoS and transmission propagation environment.

The current TCP value of cell, which is reported by Node B

（ Transmitted Carrier Power*Pmax）

Max TCP of cellService priorityReserved capacity for handover

Content



Load control

The purpose of load control is to keep the

system load under a pre-planned threshold

through several means of decreasing it, so as to

improve the system stability.

The speed and position

changing of UE may

worsen the wireless

environment.

Increased transmitted

power will increase the

system load.

Purpose of Load Control

Load Control Flows

Start

DecisionLight loaded Over loaded

Normal loaded

1.Handover in andaccess are forbidden2. TCP increase isforbidden3. RAB service ratedegrade4. Handover out5. Release call (call drop)

1. Handover in and access are allowed2. Transmitted code power (TCP) increase is allowed3. RAB service rate upgrade is allowed

1. Handover in and access are allowed2. TCP increase is allowed

Load Control in Uplink

Triggers RTWP (Received Total Wide-band Power) value from

measurement report exceeds the uplink overload threshold; Admission control is triggered when rejecting the access of

services with lower priority due to insufficient load capacity in uplink.

Methods for decreasing load Decrease the target Eb/No of service in uplink; Decrease the rate of none real time data service; Handover to GSM system; Decrease the rate of real time service, e.g. voice call; Release calls.

Methods for increasing load Increase the service rate.

Load Control in Downlink

Triggers TCP (Transmitted Carrier Power) value from measurement report

exceeds the downlink overload threshold; Admission control is triggered when rejecting the access of

services with lower priority due to insufficient load capacity in downlink.

Methods for decreasing load Decrease the downlink target Eb/No of service in downlink; Decrease the rate of none real time data service; Handover to coverage-shared light loaded carrier; Handover to GSM system; Decrease the rate of real time service, e.g. voice call; Release calls.

Methods for increasing load Increase the service rate.

Cell breathing is one of the means for load control

The purpose of cell breathing is to share the load of hot-The purpose of cell breathing is to share the load of hot-

spot cell with the light loaded neighbor cells, therefore to spot cell with the light loaded neighbor cells, therefore to

improve the utilization of system capacity.improve the utilization of system capacity.

The purpose of cell breathing is to share the load of hot-The purpose of cell breathing is to share the load of hot-

spot cell with the light loaded neighbor cells, therefore to spot cell with the light loaded neighbor cells, therefore to

improve the utilization of system capacity.improve the utilization of system capacity.

Cell Breathing Effect

Example for load control

Cell Breathing EffectCell Breathing EffectWith the increase of activated terminals and the increase of high speed services, interference will increase.

The cell coverage area will shrink.

Coverage blind spot occurs

Drop of call will happen at the edge of cell Coverage

and capacity

are interrelated

Content



WCDMA Code Resource

WCDMA code resource including Channelized Code (OVSF code)

Uplink Channelized Code Downlink Channelized Code

Scrambling Code (PN code) Uplink Scrambling Code Downlink Scrambling Code

Function of OVSF Code

OC1, OC2OC3, OC4

OC5, OC6, OC7

OC1 , OC2, OC3OC1, OC2

OC1, OC2, OC3, OC4

Uplink: distinguish different radio channels from the same UE.

Downlink: distinguish different radio channels from the same NodeB.

Function of PN code

Downlink: distinguish different Cells Uplink: distinguish different UEs

PN3 PN4

PN5 PN6

PN1 PN1

Cell Site “1” transmits using PN code 1

PN2 PN2

Cell Site “2” transmits using PN code 2

Why Code Resource Planning?

The OVSF (Orthogonal Variable Spreading Factor) code tree is a scarce resource and only one code tree can be used in each cell. In order to make full use of the capacity, and support as many connections as possible, it is important to plan and control the usage of channel code resource.

Downlink PN code allocation should be planned to avoid the interference between neighboring cells.

The uplink PN codes are sufficient, but RNC should plan the codes to use for avoiding allocating same code to different users in inter-RNC handover scenario.

Code Resource Planning

The uplink and downlink scrambling code can be planned easily by computer.

The uplink channelized code does not need planning, for every UE can use the whole code tree alone.

Therefore, only the downlink channelized code is planned with certain algorithm in RNC.

Each cell has one primary scrambling code, which correlates with a channel code tree. All the users under this cell share this single code tree, so the OVSF code resource is very limited.

The downlink channelized code tree is a typical binary tree with each layer corresponds to a certain SF ranging from SF4 to SF512.

SF = 1 SF = 2 SF = 4

Cch,1,0 = (1)

Cch,2,0 = (1,1)

Cch,2,1 = (1,-1)

Cch,4,0 =(1,1,1,1)

Cch,4,1 = (1,1,-1,-1)

Cch,4,2 = (1,-1,1,-1)

Cch,4,3 = (1,-1,-1,1)

Generation of Channelized Code

OVSF Code Tree

SF=8

SF=32

SF=16

Channelized Code Characters

Code allocation restriction ： The code to be allocated must fulfill the condition that its

ancestor nodes including from father node to root node and offspring nodes in the sub tree are not allocated;

Code allocation side effect： The allocated node will block its ancestor nodes and offspring

nodes, thus the blocked nodes will not be available for allocation until being unblocked .

Strategy of Channelized Code Allocation

Full utilization The fewer the blocked codes, the higher code tree utilization rate.

Low Complexity Short code first.

Allocate codes for common channels and physical shared channels prior to dedicated channels.

Guarantee the code allocation for common physical channels. Apply certain optimized strategy to allocate codes for downlink

dedicated physical channels.

An Example of Code Allocation

0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15

16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31

SF = 4

SF = 8

SF = 16

SF = 32

SF = 4

SF = 8

SF = 16

SF = 32

Red spots represent the codes that have been allocated；Green spots represent the codes that are blocked by the allocated offspring codes；Blue spots represent the codes that are blocked by the allocated ancestor codes;

Black spots represent the codes that to be allocated;

Choose one code from

three candidates

Planning of downlink PN code

PN1

PN2

PN3PN7

PN6 PN4

PN5

PN7

PN6 PN4

PN5

PN1

PN2

PN3

PN1

PN2

PN3PN7

PN6 PN4

PN5

PN1

PN2

PN3PN7

PN6 PN4

PN5

PN1

PN2

PN3PN7

PN6 PN4

PN5 PN1

PN2

PN3PN7

PN6 PN4

PN5

Content



RAKE Receiver can effectively overcome the multi-path RAKE Receiver can effectively overcome the multi-path

interference, consequently improve the receiving performance.interference, consequently improve the receiving performance.

RAKE Receiver can effectively overcome the multi-path RAKE Receiver can effectively overcome the multi-path

interference, consequently improve the receiving performance.interference, consequently improve the receiving performance.

RAKE Receiver

The multi-path signals contain some useful energy , therefore the CDMA receiver can combine these energy of multi-path signals to improve the received signal to noise ratio.

RAKE receiver adopts several correlation detectors to receive the multi-path signals, and then combines the received signal energy.

RAKE Receiving

d1 d2

t t t

d3

transmitti

ng

Receivin

gRake

combinationnoise

Multi-finger receiver

Traditional receiver Multi-path signals are treated as interference. The receiving performance will decline because of the

Multi-address Interference (MAI).

Precondition of Multi-finger receiver Multi-finger receiver utilizes the Multi-path Effect. Multi-finger signals can be combined through relative

process Multi-finger time delay is larger than 1 chip interval,

which is 0.26us=>78m.

Multi-finger receiver

receivertransmitter

coding decoding

Direct signal

Reflected signal

Dispersive time < 1 chip interval

Multi-finger receiver can’t supply multi-finger diversity

decodingDirect signal

Reflected signaltransmitter receiver

Dispersive time > 1 chip interval

Multi-finger receiver can supply multi-finger diversity, signal gain is improved

coding

RAKE Receiving

receiverreceiver

Single receiving

Single receiving

Single receiving

searcher calculatecalculate

combining

tt

s(t) s(t)

signal

RAKE Receiving overcomes multi-finger interference, improves receiving performance

Combination of Multi-fingers

Maximal ratio combining (MRC)

at each time delay phase shifting by adding

Finger 1

Finger 2

Finger 3

Content



Capacity of WCDMA

UL capacity is restrained by interference

DL capacity is restrained

by the power of NodeB

Power Rising

Power rising occurs because of the Multiple Access Interference (MAI) resulting from the non-orthogonal code channels.

WCDMA network Meeting Room Code channel transmit talk with dialects Channel power voice tone Promised channel quality listen clearly Channel power rise voice tone rise Power climb voice climb Collapse over the range can not hear each other

Power Rising

Quantity of Subscriber

Quantity of Subscriber-- The Total Bandwidth Received by Node B

The

Tot

al B

andw

idth

Pow

er R

ecei

ved

by N

ode

B (

dBm

)

Capacity of WCDMA System

Under the circumstance of single services:

=

=

=

Capacity of WCDMA System

…...

Under the circumstance of mixed services：

X Y Z+ +


WCDMA capacity feature WCDMA capacity is Soft Capacity.

The Concept of Soft Capacity The system capacity and communication quality are

interconvertible. Different services have different capacity. Different proportion of services have different capacity

for mixed services. The capacity is also restricted to the allocation of code

resource.

Different combination of service has different capacity

Different service has

different capacity

Concept of Soft Capacity

System capacity and QoS can be interconvertedSystem capacity and QoS can be interconverted

Quality

Quality C

over

age

Cov

erag

e

CapacityCapacity

All the key technologies adopted are used to try to All the key technologies adopted are used to try to

achieve the optimal balance of the three factorsachieve the optimal balance of the three factors

All the key technologies adopted are used to try to All the key technologies adopted are used to try to

achieve the optimal balance of the three factorsachieve the optimal balance of the three factors

Crucial Factors for WCDMA Network (CQC)

Coverage and Capacity

WCDMA performance is determined by such factors as： Number of users Transmission rate Moving speed Wireless environment

indoors Outdoors

The radius of cell depends on such factors as: Local radio conditions (local interference) Traffic in neighbouring cells (remote interference)

Cell Radius decrease according to the Increase of user number

Coverage/capacity VS Data Rate

Higher data rate needs higher power High data rate transmission is only available

nearby the station

>12.2 kbps

>64 kbps

>384 kbps

>144 kbps

Coverage decrease

Subscriber num increase

DL/UL: Add carrier six sectors

DL/UL: Add carrier six sectors

UL Tower Mounted Amplifier (TMA) 4 Rx Div OTSR

UL Tower Mounted Amplifier (TMA) 4 Rx Div OTSR

DL transmission diversity (Tx Div) high power amplifier

DL transmission diversity (Tx Div) high power amplifier

Add basestation

“last choice”

Optimization methods

To overcome Cell Breathing Effect caused by increased traffic and meet different requirements for capacity and coverage in different environment, following solutions can be applied:

Factors Impact on WCDMA capacity

Power ControlReducing interference, saving power and Increasing

capacity

Handover Control

Impacting the capacity through applying different proportion and algorithm of soft handover

Admission Control

Admitting a connection base on the load and the admission threshold of planned capacity

Load ControlMonitoring system load and adjusting the ongoing services

to avoid overload

OVSF Code The Allocation of codes impacts the maximum number of

simultaneous connections.

RAKE ReceiverThe advanced receiving and baseband processing

technology is introduced to overcome the fast fading

Wireless Environment

Wireless environment such as interferences, UE position and mobility etc. can influent the cell capacity

Factors affects WCDMA Capacity

Exercise

what is the near-far effect what is the purpose of Power Control . Power control is classify into ( ) ( )

and ( ) pls describe WCDMA Handover technology

category. Handover procedure includes ( ) ( ) and (

) What is the Cell Breathing Effect. What’s the relation between Capacity, Quality and

Coverage?

03 wr bt1004 e01_1 wcdma key technology-80

Technology

power control cdma

power control instruction

tremendouslyfpower control

new technology power

delta power

purpose of load control

ue transmitted power

increased transmitted