10 WCDMA Load Controlling

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Copyright 2006 Huawei Technologies Co., Ltd. All rights reserved.

WCDMA Load ControlWCDMA Load ControlWCDMA Load ControlWCDMA Load Control


Objectives

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

Know the load control principles

Know the load control realization methods in WCDMA system

Know The load control parameters in WCDMA system


Contents

1. Load Control Overview

2. Basic Load Control Algorithms


Load Definition

Load: the occupancy of capacity

Two kinds of capacity in CDMA system

Hard capacity

Code channels

Hard ware resource: Transport resource, NodeB processing capability (CE)

Soft capacity

Interference (UL)

Power (DL)


Uplink Load Definition

Cell Load Factor: risenoiseUL

11=NP

RTWPrisenoise =


Downlink Load Definition

R99 load control

Transmitted carrier power of all codes not

used for HS-PDSCH or HS-SCCH

transmission

DL Load R99 and HSDPA load

controlTotal Carrier Power (TCP)

HSDPA load controlHS-DSCH Required Power

HSDPA load controlHS-DSCH Provided Bit Rate

R99 load controlCell Load Factor (based on RTWP)

RTWP (Received Total Wideband Power)UL Load

ScenarioCommon Measurement in Node B


The Objectives of Load Control

Keeping system stable

Maximizing system capacity while ensuring the coverage and QoS

PUC: Potential User Control

CAC: Call Admission Control IAC: Intelligent Admission Control

LDR: Load Reshuffling OLC: Overload Control

3. After UE access2. During UE access1. Before UE access

Time

LDRCACPUC OLC

IAC


Load Control Algorithms

No Load control

PUC starts: to enable UEs in idle mode to camp on cells with light load

LDR starts: to check and release initial congestion in cells

CAC or IAC: to prevent new calls into cells with heavy load

DRD starts: to enable rejected UEs to retry neighboring cells or GSM cells

NodeB transmit

power (noise)

Cell load

OLC starts: to reduce the TFs of BE

subscribers, and release some UEs forcibly

Icons for different load levels


Load Measurement

The objectives of LDM (LoaD Measurement)

Measure the system load

Filter the measured data according to the requirement of different

load control algorithms

Major Measurement Quantities

Uplink Received Total Wideband Power (RTWP)

Downlink Transmitted Carrier Power (TCP)

TCP of all codes not used for HSDPA transmission

Power Requirement for Guaranteed Bit Rate (GBR) on HS-DSCH

Provided Bit Rate (PBR) on HS-DSCH


LDM procedure

Smooth Window Filtering on the RNC Side

N : the size of the smooth window

: the reported measurement value

1

0( )

N

n ii

PP n

N

=

=

nP


Parameters for LDM (1)

CHOICERPRTUNITFORULBASICMEAS

/CHOICERPRTUNITFORDLBASICMEAS (Time unit for UL/DL basic

meas rprt cycle)

Value Range: TEN_MSEC, MIN

Recommended value: TEN_MSEC, means the time unit is 10ms



TENMSECFORULBASICMEAS/TENMSECFORDLBASICMEAS (UL/DL

basic meas rprt cycle, Unit:10ms)

Value Range: 1~6000

Recommended value: 20, namely 200ms

MINFORULBASICMEAS/MINFORDLBASICMEAS (UL/DL basic meas

rprt cycle, Unit: min)

Value Range: 1~60

Recommended value: none



ULBASICCOMMMEASFILTERCOEFF /

DLBASICCOMMMEASFILTERCOEFF (UL/DL basic common measure

filter coeff)

Value Range: D0, D1, D2, D3, D4, D5, D6, D7, D8, D9, D11, D13,

D15, D17, D19

Recommended value: D6



The parameters for smoothing filter window

25132DlOLCAvgFilterLenDL OLC moving average filter length

25132UlOLCAvgFilterLenUL OLC moving average filter length

3132DlCACAvgFilterLenDL CAC moving average filter length

3132UlCACAvgFilterLenUL CAC moving average filter length

25132DlLdrAvgFilterLenDL LDR moving average filter length

25132UlLdrAvgFilterLenUL LDR moving average filter length

32132PucAvgFilterLenPUC moving average filter length

Recommend

ValueValue RangeParameter IDParameter Name


Parameters for HSDPA LDM (1)

CHOICERPRTUNITFORHSDPAPWRMEAS (Time unit of HSDPA

need pwr meas cycle)



CHOICERPRTUNITFORHSDPARATEMEAS (Time unit of HSDPA bit

rate meas cycle)





TENMSECFORHSDPAPWRMEAS (HSDPA need pwr meas

cycle,Unit:10ms)

Value Range: 1~6000


TENMSECFORHSDPAPRVIDRATEMEAS (HSDPA bit rate meas

cycle,Unit:10ms)

Value Range: 1~6000




MINFORHSDPAPWRMEAS (HSDPA need pwr meas cycle, Unit:

min)

Value Range: 1~60


MINFORHSDPAPRVIDRATEMEAS (HSDPA bit rate meas cycle,

Unit: min)

Value Range: 1~60




HSDPANEEDPWRFILTERLEN (HSDPA need power filter len)

Value Range: 1~32

Recommended value: 1

HSDPAPRVIDBITRATEFILTERLEN (HSDPA bit rate filter len)

Value Range: 1~32



Priority

The service of user with low priority will be affected by the load

control algorithms first

Three kinds of priority

User Priority

User Integrate Priority

RAB Integrate Priority


User Priority

There are three levels of user priority (1, 2, and 3)

gold (high), silver (middle) and copper (low) user

32kbps64kbps128kbpsUplink

CopperSilverGoldUser priority

32kbps64kbps128kbpsDownlink

gold

userPay $100

for 3G

services


User Priority

The relationship between user priority and ARP is configurable

The typical relationship as follow:

The relationship can be configured through SET USERPRIORITY,

and queried through LST USERPRIORITY

33332222211111User Priority

1413121110987654321ARP


RAB Integrate Priority

The values of RAB Integrate Priority are set according to the

following parameters

PRIORITYREFERENCE (Integrated Priority Configured Reference)

Value rangeValue rangeValue rangeValue range: ARP, TrafficClass

Recommended valueRecommended valueRecommended valueRecommended value: ARP

CARRIERTYPEPRIORIND (Indicator of Carrier Type Priority)

Value rangeValue rangeValue rangeValue range: DCH, HSDPA

Recommended valueRecommended valueRecommended valueRecommended value: DCH


Example for RAB Integrate Priority

DCHBackground2D

DCHConversational2C

HSDPAInteractive1B

DCHInteractive1A

Bear

type

Traffic ClassARPService

ID

Services attribution in the cell

Based on ARP, HSDPA priority is higher

Based on Traffic Class, HSDPA priority is higher

DCHBackground2D

DCHConversational2C

DCHInteractive1A

HSDPAInteractive1B

Bear

type

Traffic ClassARPService

ID

Background

Interactive

Interactive

Conversational

Traffic Class

DCH2D

DCH1A

HSDPA1B

DCH2C

Bear

type

ARPService

ID


User Integrate Priority

For multiple-RAB users, the integrate priority of the user is based

on the service of the highest priority. User integrate priority is

mainly used to select different users during LDR/OLC.


Contents



2.1 PUC (Potential User Control)

2.2 CAC (Call Admission Control)

2.3 IAC (Intelligent Admission Control)

2.4 LDR (Load Reshuffling)

2.5 OLC (Overload Control)


PUC Principles

Freq1

Freq2

System InfoSIB3,11

System InfoSIB3,11

System InfoSIB3,11

Heavy load

Light load Normal load

Idle state CCH state

Modify1.Easy to trigger reselection2.Easy to select light loadInter-freq neighbor Cell

Decrease the POTENTIAL load

Modify1.Hard to trigger reselection2.Easy to camp on the cell

Increase the POTENTIAL loadStay


PUC Realization

PUC can modify inter-frequency cell reselection parameters to

control the user distribution between cells.

Sintersearch: when the load of a cell is Heavy, PUC will increase

this parameter; when the load of a cell is Light, PUC will decrease

this parameter.

QOffset1sn and QOffset2sn: when the load of a cell is Heavy,

PUC will decrease these parameters; when the load of a cell is

Light, PUC will increase these parameters.


Parameters for PUC Algorithm Switch

NBMLDCALGOSWITCH (Cell LDC algorithm switch)

Value Range:

PUC

Default status: None

PUCPERIODTIMERLEN (PUC period timer length)

Value Range:6s~86400s

Default value: 1800, namely 1800 seconds, i.e. 30 minutes


Parameters for PUC (1)

SPUCHEAVY (Load level division threshold 1)

Value Range: 0 to 100%

Recommended value: 70, namely 70%

SPUCLIGHT (Load level division threshold 2)



SPUCHYST (Load level division hysteresis)





OFFSINTERLIGHT (Sintersearch offset 1)

Value Range: -10 to 10

Physical Value Range: -20 to 20dB, step 2dB

Recommended value: -2, namely -4dB

OFFSINTERHEAVY (Sintersearch offset 2)



Recommended value: 2, namely 4dB



OFFQOFFSET1LIGHT (Qoffset1 offset 1)




OFFQOFFSET2LIGHT (Qoffset2 offset 1)






OFFQOFFSET1HEAVY (Qoffset1 offset 2)




OFFQOFFSET2HEAVY (Qoffset2 offset 2)





Contents









Why we need CAC?

WCDMA is an interference limited system, after a new call is

admitted, the system load will be increased

If a cell is high loaded, a new call will cause ongoing user

dropped

We must keep the coverage planned by the Radio Network

Planning


Flow chart of CAC


CAC Code Resource Admission

For handover services

The current remaining code resource should be enough for the

service

For other R99 services

RNC shall ensure the remaining code does not exceed the

configurable OM thresholds after admission of the new service

For HSDPA services

The code resource admission is not needed


Parameters for Code Resource Admission

DLHOCECODERESVSF (DL HandOver Credit and Code Reserved

SF)

Value Range:0, 1, 2, 3, 4, 5, 6, 7

Physical value Range: SF4, SF8, SF16, SF32, SF128, SF256,

SFOFF

Recommended value: SF32

Configuration Rule and Restriction:

[Dl HandOver Credit and Code Reserved SF] >= max ([Dl LDR Credit SF

reserved threshold], [Cell LDR SF reserved threshold])


CAC Power Resource Admission

Algorithm 1: based on UL/DL load measurement and load

prediction (RTWP and TCP)

The algorithm is easy to implement, but it is affected by the result

of RTWP and TCP measurement

Algorithm 2: based on Equivalent Number of User (ENU)

The algorithm is no need to measure RTWP and TCP, but the

calculation is more complex

Algorithm 3: loose call admission control algorithm

Similar to algorithm 1, but the prediction of needed power of a

new call will be set to zero


Uplink CAC Algorithm 1 - Load Prediction

Get current RTWP, and calculate the

current load factor

Admission request

Get the traffic characteristic, and

estimate the increment of load factor

Calculate the predicted load factor

admitted rejected

End of UL CAC

Y NSmaller than the

threshold?

RTWPPN

UL = 1

+= ULpredictedUL _


Downlink CAC Algorithm 1 - Load Prediction

Get current TCP

Admission request


estimate the increment of TCP

Calculate the predicted TCP

admitted rejected

End of DL CAC

Y NSmaller than the

threshold?

)(NP

P

PNP +)(


Uplink and Downlink CAC Algorithm 2 - ENU

Get current total ENU

Admission request


estimate the increment of ENU

Calculate the predicted ENU

admitted rejected

End of UL/DL CAC

Y NSmaller than the

threshold?

=

=

N

iitotal ENUNENU

1)(

newENU

newtotaltotal ENUNENUNENU +=+ )()1(

max/)1( ENUNENUENULoad total +=


Typical equivalent number of users

3.9114.1715.5214.273.4 + 384 kbit/s (PS)

2.839.3610.4910.183.4 + 256 kbit/s (PS)

1.915.466.616.413.4 + 144 kbit/s (PS)

1.674.925.935.783.4 + 128 kbit/s (PS)

1.22.793.253.453.4 + 64 kbit/s (PS)

0.961.72.192.153.4 + 32 kbit/s (PS)

0.851.111.251.623.4 + 16 kbit/s (PS)

0.840.781.041.353.4 + 8 kbit/s (PS)

--1.421.443.4 + 12.2 kbit/s

--1.111.1113.6 kbit/s SIG

--0.420.443.4 kbit/s SIG

HSUPAHSDPADownlink for DCHUplink for DCH

ENUService


Parameters for Power Resource

Admission Algorithm Switch NBMULCACALGOSELSWITCH (Uplink CAC algorithm switch)

Value Range:

ALGORITHM_OFF, ALGORITHM_FIRST, ALGORITHM_SECOND, and

ALGORITHM_THIRD

NBMDLCACALGOSELSWITCH (Downlink CAC algorithm switch)

Value Range:

ALGORITHM_OFF, ALGORITHM_FIRST, ALGORITHM_SECOND, and

ALGORITHM_THIRD


Parameters for Load Prediction (1)

CELLENVTYPE (Cell environment type)

Value Range:

TU: typical urban district RA: rural area HT: hill terrain

Default value: TU

BACKGROUNDNOISE (Background noise)

Value Range: 0 to 621

Physical Range: -112 to -50dBm, step: 0.1

Recommended value: 71, namely -105dBm


Parameters for Load Prediction (2)

ULINTERFACTOR (UL neighbor interference factor )


Physical Range: 0 to 2, step: 0.01

Recommended value: 60, namely 0.6

NONORTHOFACTOR (DL Nonorthogonality factor)


Physical Range: 0 to 1, step: 0.001

Recommended value: 400, namely 0.4



Admission (1) ULCCHLOADFACTOR (UL common channel load factor)

Value range: 0 to 100%


DLCCHLOADRSRVCOEFF (DL common channel load reserved

coefficient)





Admission (2) ULCONVAMRTHD (UL threshold of Conv AMR service)



ULCONVNONAMRTHD (UL threshold of Conv non_AMR service)





Admission (3) ULOTHERTHD (UL threshold of other services)



ULHOTHD (UL handover access threshold)





Admission (4) DLCONVAMRTHD (DL threshold of Conv AMR service)



DLCONVNONAMRTHD (DL threshold of Conv non_AMR service)





Admission (5) DLOTHERTHD (DL threshold of other services)



DLHOTHD (DL handover access threshold)





Admission (6) ULTOTALEQUSERNUM (UL total equivalent user number)

Value range: 1 to 200

Recommended value: 80, namely UL ENUmax = 80

DLTOTALEQUSERNUM (DL total nonhsdpa equivalent user

number)


Recommended value: 80, namely DL ENUmax = 80


CAC Credit Resource Admission

Credit resource admission is similar with code resource

admission

For handover services

The current remaining credit resource should be enough for the

service

For other R99 services

RNC shall ensure the remaining code does not exceed the

configurable thresholds after admission of the new service


Parameters for Credit Resource

Admission (1) DLHOCECODERESVSF (DL HandOver Credit and Code Reserved

SF)

Value Range:0, 1, 2, 3, 4, 5, 6, 7


SFOFF



[Dl HandOver Credit and Code Reserved SF] >= max ([Dl LDR Credit SF

reserved threshold], [Cell LDR SF reserved threshold])


Parameters for Credit Resource

Admission (2) ULHOCERESVSF (Ul HandOver Credit Reserved SF)

Value Range:0, 1, 2, 3, 4, 5, 6, 7


SFOFF



[Ul HandOver Credit Reserved SF] >= Ul LDR Credit SF reserved threshold


Contents









Why we need IAC?

The disadvantage of CAC:

For PS NRT (Non-Real Time) services, CAC is not flexible

No consideration about the priority of different users

No consideration about Directed Retry after CAC rejection

Intelligent means the algorithm can increase admission

successful rate


Flow chart of IAC


IAC Rate negotiation

Iu QoS Negotiation: based on

the UE capability

Physical layer capability

Transport channel capability

RLC capability

RAB Downsizing: based on

system load

Channelization codes

Iub transmission resources

Radio resources

384kbps

256kbps

128kbps

64kbps

32kbps

Maximum allowed bit rate

Initial / Target data rate

Scenarios: RAB setupRAB modify, SRNSR request, reconfiguration


IAC Direct Retry based on service

Data service can be retry to HSDPA cells for better QoS

Data service

HSDPACELL AFrequency B

R99CELL2 R99 CELL 1Frequency A


IAC Preemption

Low priority

High priority

Preempting resource

The user with high priority can preempt the resource of users

with low priority

Triggering resource for Preemption

Power (or ENU), SF (spreading factor), Iub transmission resource,

NodeB CE


IAC Queuing

After CAC rejection, UE can wait a moment and queue, then try

to admit again

Queuing priority: Pqueue = Tmax Telapsed

Tmax is the maximum time in the queue, default value is 5s

Telapsed is the time has queued


IAC Directed Retry based on Load Balance Service will be set up to the cell with lightest load

The advantages

Keeping the load of the network balanced

Supporting higher data rate for the user

Cell 1

Cell 2

RRC

Connection

Cell 1

Cell 2

RAB


Parameters for IAC Algorithm Switch (1)

IU_QOS_NEG_SWITCH (Switcher for IU QoS Negotiation)

Value range: 0 (close), 1 (open)

Default value: 0

RAB_DOWNSIZING_SWITCH (RAB Downsizing Switch)

Value range: 0 (close), 1 (open)

Default value: 1


Parameters for IAC Algorithm Switch (2)

PREEMPTALGOSWITCH (Preempt algorithm switch)

Value range: On, Off

Default value: Off

QUEUEALGOSWITCH (Queue algorithm switch)

Value range: On, Off

Default value: Off


Parameters for RAB Downsizing

ULBETRAFFINITBITRATE (Uplink BE traffic initial access rates) &

DLBETRAFFINITBITRATE (Downlink BE traffic initial access rates)

Value range: D8, D16, D32, D64, D128, D144, D256, D384,

D768, D1024, D1536, D2048

Physical Value range: 8, 16, 32, 64, 128, 144, 256, 384, 768,

1024, 1536, 2048, Unit: kbps

Default value: D64, namely 64kbps


Parameters for Queuing (1)

QUEUELEN (Queue length)



POLLTIMERLEN (Poll timer length)


Physical value range: 10 to 60000 ms step: 10ms

Recommended value: 50, namely 500 ms


Parameters for Queuing (2)

MAXQUEUETIMELENx (Max queuing time length 1~12)

Value range: 1 to 60s

Recommended value: 5, namely 5 seconds


Parameters for DRD (1)

DRMAXUMTSNUM (Max inter-frequency direct retry number)

Value range: 0 to 5



Parameters for DRD (2)

R99CSSEPIND (R99 CS separation indicator)

Value range: FALSE (no separation), TRUE (separation)

Recommended value: FALSE

R99PSSEPIND (R99 PS separation indicator)

Value range: FALSE (no separation), TRUE (separation)

Recommended value: FALSE


Contents









LCC (Load Congestion Control)

Overload state: OLC will be used

L

o

a

d

%

THLDR

THOLC

100%section A

section B

section C

1 2

Normal state: Permit entry

Times

Basic congestion state: LDR

will be used


LDR (Load Reshuffling)

Reasons

When the cell is in basic congestion state, new coming calls could

be easily rejected by system

Purpose

Optimizing cell resource distribution

Decreasing load level, increasing admission successful rate

Triggering of LDR

Power resources, code resource, Iub resources or Iub bandwidth,

NodeB Credit resource


LDR Procedure Mark "current LDR state = uncongested"

Wait for congestion indicationCongestion

state indication

Turn on LDR algorithm switch

Current LDR state = congested?

Start LDM congestion indication report

Mark "current action = first LDR action"

Clear "selected" mark of all UE LDR actions

Sequence ofactions can be

configured(current actionis taken firstly)

Inter-systemhandover

in CS domain

AMR ratereduction

Inter-freqload handover

QoS renogiationon Iu interface

BE ratereduction

Succeed?

Mark"current action= successful

action"

Wait timefor LDR

action duration

Y

Y

Y

Y

Y

N

N

N

N

N

N

Mark "current action = first LDR action"No related action can be found

N

Inter-systemhandover

in PS domain

Succeed?

Succeed?

Succeed?

Succeed?

Succeed?

Codereshuffling Succeed?

Y

N

MBMS powerreduction

NSucceed?

Y

Y


LDR Actions


LDR Actions - Inter-frequency Load

Handover Target cells

Load difference between current load and the basic congestion

trigger threshold of target cell is larger than UL/DL Inter-freq cell

load handover load space threshold

Target users

Based on user priority and the current service rate

Result

The load of two cells is lower than the basic congestion trigger

threshold

The user with low priority handover to the Light load cells


LDR Actions - BE Rate Reduction

Candidate RABs

The data rate of BE service is larger than GBR

Target RABs

Rank the candidate RABs by the integrate priority, the low priority

RABs reduce BE rate first

Result

Cell load is decreased under basic congestion trigger threshold

The BE service rate of low priority RABs is limited in GBR


LDR Actions - Uncontrolled Real-time

QoS Renegotiation Target RABs

Rank the candidate RABs by the integrate priority, the service with

lowest priority and current data rate higher than GBR will be

selected

Result


The data rate of low priority service is reduced to GBR


LDR Actions - Inter-system Handover In

the CS/PS Domain Target user

Based on the integrate priority, sorting the UEs in descending

order. The top CS/PS services are selected

Result


WCDMA cell

GSM cell


LDR Actions - AMR Rate Reduction

Target user (downlink e.g.)

Candidate RABs: users accessing the AMR services (conversational)

and with the bit rate higher than the GBR

Rank the candidate RABs by the integrate priority, the AMR service

with lowest priority will be selected

Result


The AMR user with low priority is reduced to low voice rate mode


LDR Actions - Code Reshuffling

Purpose


Sufficient code resources can be reserved for subsequent service


LDR Actions - MBMS Power Reduction

Purpose

The downlink power load can be reduced by lowering power on

MBMS traffic channels


Parameters for LDR Algorithm Switch

NBMLdcAlgoSwitch (Cell algorithm switch)

Value Range:

ULLDR, DLLDR, CELL_CODE_LDR, CELL_CREDIT_LDR

Default status: OFF

Most of the LDR actions (except inter-frequency load handover) affect

QoS


Parameters for LDR Algorithm Priority

Priority for load reshuffling

Value Range:

IUBLDR(Iub load reshuffling), CREDITLDR(Credit load reshuffling),

CODELDR (Code load reshuffling), UULDR (Uu load reshuffling)

Default status:

LdrFirstPri = IUBLDR

LdrSecondPri = CREDITLDR

LdrThirdPri = CODELDR

LdrFourthPri = UULDR


Parameters for Triggering of Power

Resource (1) ULLDRTRIGTHD (UL LDR trigger threshold)



ULLDRRELTHD (UL LDR release threshold)




Parameters for Triggering of Power

Resource (2) DLLDRTRIGTHD (DL LDR trigger threshold)



DLLDRRELTHD (DL LDR release threshold)




Parameters for Triggering of Code

Resource and Credit Resource CELLLDRSFRESTHD (Cell LDR SF reserved threshold)

Value Range:0, 1, 2, 3, 4, 5, 6, 7

Physical value Range: SF4, SF8, SF16, SF32, SF128, SF256


UL (DL) LDRCREDITSFRESTHD (UL/DL LDR Credit SF reserved threshold ) Value Range:0, 1, 2, 3, 4, 5, 6, 7

Physical value Range: SF4, SF8, SF16, SF32, SF128, SF256



Parameters for LDR Period

LDRPERIODTIMERLEN (LDR period timer length)

Value range: 1 to 86400 unit: second

Recommended value: 10, namely 10s

Not less than 8s


Parameters for LDR Action Sequence

UL (DL) LDRFIRSTACTION (UL/DL LDR First action) ~

UL (DL) LDRSIXTHACTION (UL/DL LDR Sixth action)

Value range: NOACT, INTERFREQLDHO, BERATERED,

QOSRENEGO, CSINTERRATLDHO, PSINTERRATLDHO,

AMRRATERED, MBMSDECPOWER, CODEADJ

Default value: UlLdrFirstAction or DlLdrFirstAction is CODEADJ,

UlLdrSecondAction or DlLdrSecondAction is INTERFREQLDHO

UlLdrThirdAction or DlLdrThirdAction is BERATEREDthe other is NOACT


Parameters for LDR Code Reshuffling

MAXUSERNUMCODEADJ (Max user number of code adjust)

Value range: 1 to 3


LDRCODEPRIUSEIND (LDR code priority indicator)

Value range: FALSE, TRUE

Recommended value: TRUE


Parameters for LDR Inter-Frequency

Load Handover (1) ULINTERFREQHOCELLLOADSPACETHD (UL Inter-freq cell load

handover load space threshold)



DLINTERFREQHOCELLLOADSPACETHD (DL Inter-freq cell load

handover load space threshold)




Parameters for LDR Inter-Frequency

Load Handover (2) ULINTERFREQHOBWTHD (UL Inter-freq cell load handover

maximum bandwidth)

Value range: 0 to 400000bps

Recommended value: 200000, namely 200kbps

DLINTERFREQHOBWTHD (DL Inter-freq cell load handover

maximum bandwidth)

Value range: 0 to 400000bps

Recommended value: 200000, namely 200kbps


Parameters for LDR Other Actions

UL (DL) LDRBERATEREDUCTIONRABNUM,

UL (DL) LDRPSRTQOSRENEGRABNUM,

UL (DL) LDRCSINTERRATHOUSERNUM,

UL (DL) LDRPSINTERRATHOUSERNUM,

UL (DL) LDRAMRRATEREDUCTIONRABNUM


Default value

UL (DL) LDRBERATEREDUCTIONRABNUM: 1

UL (DL) LDRPSRTQOSRENEGRABNUM: 1

UL (DL) LDRCSINTERRATHOUSERNUM: 3

UL (DL) LDRPSINTERRATHOUSERNUM: 1

UL (DL) LDRAMRRATEREDUCTIONRABNUM: 3


Contents









OLC (Over Load Control)

Reasons

In overload state, system is not stable

Purpose

Ensuring the system stability and making the system back to the

normal state as soon as possible

Triggering of OLC

Power resources

Interference


OLC Procedure


OLC Actions - TF Control

Target user

Rank the candidate users by the integrate priority, the low priority

user will be selected

Execution

Send the control message to UE (downlink: TF control indication,

uplink: Transport format combination control) to restricts the TFC

selection

After the congestion is released, the BE service rate will be

recovered


OLC Actions - Switching BE Services to

Common Channel Target user (downlink e.g.)

Rank the candidate users that have only PS services by the

integrate priority, the low priority user will be selected

Execution

The selected UEs are switched to common channel


OLC Actions - Release of Some RABs

Target user (downlink e.g.)

Rank the candidate users by the integrate priority, the low priority

user will be selected

Execution

The selected RABs are released directly.


Parameters for OLC Algorithm Switch

NBMLDCALGOSWITCH (Cell LDC algorithm switch)

Value Range:

ULOLC, DLOLC

Default status: OFF

OLC actions affect QoS heavily


Parameters for Triggering of Overload (1)

ULOLCTRIGTHD (UL OLC trigger threshold)



ULOLCRELTHD (UL OLC release threshold)




Parameters for Triggering of Overload (2)

DLOLCTRIGTHD (DL OLC trigger threshold)



DLOLCRELTHD (DL OLC release threshold)




Parameters for OLC (1)

OLCPERIODTIMERLEN (OLC period timer length)

Value range: 100 to 86400000, unit: ms




ULOLCFTFRSTRCTTIMES (UL OLC fast TF restrict times)



DLOLCFTFRSTRCTTIMES (DL OLC fast TF restrict times)





ULOLCFTFRSTRCTRABNUM (UL OLC fast TF restrict RAB number)



DLOLCFTFRSTRCTRABNUM (DL OLC fast TF restrict RAB number)





RATERSTRCTCOEF (DL OLC fast TF restrict data rate restrict

coefficient)





RATERSTRCTTIMERLEN (DL OLC fast TF restrict data rate restrict

timer length)



RATERECOVERTIMERLEN (DL OLC fast TF restrict data rate

recover timer length)





TRANSCCHUSERNUM (Transfer Common Channel User

number)


Default value: 1



ULOLCTRAFFRELRABNUM (UL OLC traff release RAB number)


Default value: 0

DLOLCTRAFFRELRABNUM (DL OLC traff release RAB number)


Default value: 0


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10 WCDMA Load Controlling

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