Huawei WCDMA Load Control

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www.huawei.com

WCDMA Load Control

The WCDMA system is a self interference system. As the load of the WCDMA system increases, the interference rises. A relatively high interference may affect the coverage and Quality of Service (QoS) of established services. Therefore, capacity, coverage and QoS of the WCDMA system are mutually affected. The purpose of load control is to maximize the system capacity while ensuring coverage and QoS.

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2 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

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1. Load Control Overview

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4 1. Load Control Overview

2. Basic Load Control Algorithms

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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)

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6 Uplink Load Definition

Cell Load Factor:

rise

noise

UL

1

1 −

=

η

N

P

RTWP

rise

noise

=

PN: Background noise

In the uplink, the RTWP value can be measured easily. Therefore, the UL cell load factor (based on RTWP) can be used to describe UL load.

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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 control Total Carrier Power (TCP)

HSDPA load control HS-DSCH Required Power

HSDPA load control HS-DSCH Provided Bit Rate

R99 load control Cell Load Factor (based on RTWP)

RTWP (Received Total Wideband Power)

UL Load

Scenario Common Measurement in Node B

The definition of DL load is very different from the definition of UL load, the adjacent cell interference factor and the non-orthogonality factor in the downlink are very difficult to measure and calculate, therefore, the DL cell load factor can not be used to describe the DL cell load. Then, the transmission power is used to describe DL load.

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8 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 access 2. During UE access 1. Before UE access Time • LDR CAC PUC • OLC • • IAC

Load control algorithm can be classified into three parts according to the different working states of UE.

Before UE accesses, the PUC algorithms will function. RNC will monitor the cell

load periodically. If the current cell load exceeds a specific threshold, RNC will modify the cell selection and re-selection parameters, in order that UE can select the low-load cell easily when UE will initiate some services and work at CELL-DCH state. This algorithm aims at UE which working at IDLE mode, CELL-FACH state, CELL-PCH state or URA-PCH state in this cell.

During UE accesses, the CAC and IAC algorithms will function. RNC will judge

whether the new access is admissible.

After UE accesses, LDR and OLC algorithms will function. There are some

practical algorithms to decrease the cell load. When a cell is in basic congestion, the RNC shall select some UEs for inter-frequency handover. When a cell is in overload congestion, the RNC shall select some UEs to release if failing to release the cell from overload congestion by BE service TF control.

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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

In a cell, the higher the cell load, the higher the NodeB transmit power (noise). In this diagram, different icons indicates different load levels. And for different load levels, the different load control algorithm will function.

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10 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

For LDR and OLC algorithms, the LDM algorithm needs to decide whether the system works in basic congestion or overload congestion mode and to notify related algorithms for handling.

Delay susceptibilities of PUC, CAC, LDR, and OLC to common measurement are different. When some or all the algorithms use the same common measurement, the LDM must apply different smoothed filter coefficients in order to get rippling and timely common measurement as required.

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LDM procedure

Smooth Window Filtering on the RNC Side

N : the size of the smooth window

: the reported measurement value

1 0

( )

N n i i

P

P n

N

− − =

=

∑

n

P

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12 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

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Parameters for LDM (2)

TENMSECFORULBASICMEAS/TENMSECFORDLBASICMEA

S (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

Notes:

1. [LDR period timer length] and [OLC period timer length] which are configured in the command SET LDCPERIOD must be twice greater than the UL basic common measurement report cycle.

2. [Intra-frequency LDB period timer length], [PUC period timer length], [LDR period timer length] and [OLC period timer length] which are configured in the command SET LDCPERIOD must be twice greater than the DL basic common measurement report cycle.

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14 Parameters for LDM (3)

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

ULBASICCOMMMEASFILTERCOEFF / DLBASICCOMMMEASFILTERCOEFF (UL/DL basic common measure filter coeff)

This parameter specifies the L3 filtering coefficient of the measurement value on the NodeB side. The greater this parameter is, the greater the smoothing effect and the higher the anti slow fading capability, but the lower the signal change tracing capability. The change of this parameter has an effect on PUC, CAC, LDR algorithms.

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Parameters for LDM (4)

The parameters for smoothing filter window

25 1–32

DlOLCAvgFilterLen DL OLC moving average filter length

25 1–32

UlOLCAvgFilterLen UL OLC moving average filter length

3 1–32

DlCACAvgFilterLen DL CAC moving average filter length

3 1–32

UlCACAvgFilterLen UL CAC moving average filter length

25 1–32

DlLdrAvgFilterLen DL LDR moving average filter length

25 1–32

UlLdrAvgFilterLen UL LDR moving average filter length

32 1–32

PucAvgFilterLen PUC moving average filter length

Recommend Value Value Range Parameter ID

Parameter Name

These parameters specify the length of smoothing filter window of the report measurement value on the RNC side. The greater these parameters are, the greater the smoothing effect, but the lower the signal change tracing capability.

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16 Parameters for HSDPA LDM (1)

CHOICERPRTUNITFORHSDPAPWRMEAS (Time unit of

HSDPA need pwr

meas cycle)

Value Range: TEN_MSEC, MIN

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

CHOICERPRTUNITFORHSDPARATEMEAS (Time unit of

HSDPA bit rate

meas cycle)

Value Range: TEN_MSEC, MIN

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Parameters for HSDPA LDM (2)

TENMSECFORHSDPAPWRMEAS (

HSDPA need pwr

meas

cycle,Unit:10ms)

Value Range: 1~6000

Recommended value: 10, namely 100ms

TENMSECFORHSDPAPRVIDRATEMEAS (

HSDPA bit rate

meas cycle,Unit:10ms)

Value Range: 1~6000

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18 Parameters for HSDPA LDM (3)

MINFORHSDPAPWRMEAS (

HSDPA need pwr

meas cycle,

Unit: min)

Value Range: 1~60

Recommended value: none

MINFORHSDPAPRVIDRATEMEAS (

HSDPA bit rate

meas

cycle, Unit: min)

Value Range: 1~60

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Parameters for HSDPA LDM (4)

HSDPANEEDPWRFILTERLEN (

HSDPA need power

filter len)

Value Range: 1~32

Recommended value: 1

HSDPAPRVIDBITRATEFILTERLEN (

HSDPA bit rate

filter len)

Value Range: 1~32

Recommended value: 1

These parameters specify the length of the smoothing filter window of HSDPA power and bit rate requirement.

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20 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: mainly applying to provide different QoS for different users. Eg., setting different GBR according to the level of users for BE service.

User Integrate Priority: defining different ARP (Allocation/Retention Priority) to the user with the same User Priority.

RAB Integrate Priority: considering ARP, traffic class, THP (Traffic Handling Priority) synthetically.

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User Priority

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

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

32kbps

64kbps

128kbps

Uplink

Copper

Silver

Gold

User priority

32kbps

64kbps

128kbps

Downlink

gold user Pay $100 for 3G services

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22 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

3 3 3 3 2 2 2 2 2 1 1 1 1 1 User Priority 14 13 12 11 10 9 8 7 6 5 4 3 2 1 ARP

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RAB Integrate Priority

The values of RAB Integrate Priority are set according to the

following parameters

PRIORITYREFERENCE (Integrated Priority Configured

Reference)

Value range: ARP, TrafficClass Recommended value: ARP

CARRIERTYPEPRIORIND (Indicator of Carrier Type Priority)

Value range: DCH, HSDPA

Recommended value: DCH

Set the parameter through SET USERPRIORITY, and query it through LST

USERPRIORITY.

If the value of the parameter is set to Traffic Class, the integrate priority abides by the following rules:

•Classes of services: conversational -> streaming -> interactive -> background •Services of the same class: priority based on Allocation/Retention Priority (ARP) values

•Only for the interactive service of the same ARP value: priority based on THP •Services of the same class and priority: HSDPA or DCH service preferred on the basis of the value of the Indicator of Carrier Type Priority parameter

If the value of the parameter is set to ARP, the integrate priority abides by the following rules:

•ARP1 -> ARP2 -> ARP3 … -> ARP14

•Same ARP value: conversational -> streaming -> interactive -> background •THP

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24 Example for RAB Integrate Priority

DCH Background 2 D DCH Conversational 2 C HSDPA Interactive 1 B DCH Interactive 1 A Bear type Traffic Class ARP Service ID

Services attribution in the cell

Based on ARP, HSDPA priority is higher

Based on Traffic Class, HSDPA priority is higher

DCH Background 2 D DCH Conversational 2 C DCH Interactive 1 A HSDPA Interactive 1 B Bear type Traffic Class ARP Service ID Background Interactive Interactive Conversational Traffic Class DCH 2 D DCH 1 A HSDPA 1 B DCH 2 C Bear type ARP Service ID

When the user just has one RAB, User integrate priority is the same as the service of the RAB integrate priority;

For multiple RAB users, the integrate priority of the user is based on the service of the highest priority.

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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.

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26

1. Load Control Overview

2. Basic Load Control Algorithms

2.1 PUC (Potential User Control)

2.2 CAC (Call Admission Control)

2.3 IAC (Intelligent Admission Control)

2.4 LDR (Load Reshuffling)

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1. Load Control Overview

2. Basic Load Control Algorithms

2.1 PUC (Potential User Control)

2.2 CAC (Call Admission Control)

2.3 IAC (Intelligent Admission Control)

2.4 LDR (Load Reshuffling)

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28 PUC Principles

Freq1 Freq2 System Info SIB3,11,12 System Info SIB3,11,12 System Info SIB3,11,12 Heavy load

Light load Normal load

Idle state CCH state

Modify

1.Easy to trigger reselection 2.Easy to select light load Inter-freq neighbor Cell Decrease the POTENTIAL load

Modify

1.Hard to trigger reselection 2.Easy to camp on the cell Increase the POTENTIAL load

Stay

The function of PUC is to balance traffic load among inter-frequency cells. By modifying cell selection and reselection parameters and broadcasting them through system information, PUC leads UEs to cell with light load. The UE may be in idle mode, Cell_FACH state, Cell _PCH state, URA_PCH state

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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.

According to the load level of a cell, system will adjust the cell-reselection parameters in SIB3, 11 and 12:

1. Sintersearch:

When the UE detects that the quality of the service cell (CPICH Ec/N0 measured by the UE) is lower than the sum of the minimum quality criterion of the service cell (Qqualmin) plus this threshold, it will start the inter-frequency cell reselection process.

If this parameters are too high, cell reselection will probably start frequently, resulting in UE battery waste; If they are too low, cell reselection will probably start difficultly.

2. QOffset1sn and QOffset2sn:

These parameters are offsets of CPICH measured values of neighboring cells. QOffset1sn is used for the RSCP measurement and the neighboring cell

measurement value participates in cell reselection sequencing after this offset is deducted from it. QOffset2sn is used for the Ec/No measurement and the

neighboring cell measurement value participates in cell reselection sequencing after this offset is deducted from it.

The bigger these values are, the smaller the probability of selecting the neighboring cell will be; the smaller these values are, the bigger the probability of selecting the neighboring cell will be.

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30 Parameters for PUC Algorithm Switch

NBMSWITCH (Cell algorithm switch)

Value Range:

PUC

Default status: OFF

PUCPERIODTIMERLEN (PUC period timer length)

Value Range:6s~86400s

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

Set PUC Algorithm Switch through ADD CELLALGOSWITCH, query it through

LST CELLALGOSWITCH, and modify it through MOD CELLALGOSWITCH.

Set PUC period timer through SET LDCPERIOD, query it through LST

LDCPERIOD.

Note: [PUC period timer length must be twice greater than the DL basic common measurement report cycle (default value is 200ms).

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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)

Value Range: 0 to 100%

Recommended value: 45, namely 45%

SPUCHYST (Load level division hysteresis)

Value Range: 0 to 100%

Recommended value: 5, namely 5%

Set the following parameters through ADD CELLPUC, query it through LST

CELLPUC, and modify it through MOD CELLPUC.

SPUCHEAVY (Load level division threshold 1):

It is used to decide whether the cell load level is "Heavy" or not. If the load of a cell is equal to or higher than this threshold, the load level of this cell is heavy. If the load level of a cell is heavy, the PUC algorithm will configure selection/reselection parameters for this cell to lead the UE camping on this cell to reselect another inter-frequency neighboring cell with light load.

SPUCLIGHT (Load level division threshold 2):

It is used to decide whether the cell load level is "Light" or not. If the load of a cell is equal to or lower than this threshold, the load level of this cell is light. If the load level of a cell is light, the PUC algorithm will configure selection/reselection parameters for this cell to lead the UE to reselect this cell rather than the previous inter-frequency neighboring cell with heavy load.

SPUCHYST (Load level division hysteresis):

The hysteresis used while judging cell load level, it is used to avoid the

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32 Parameters for PUC (2)

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)

Value Range: -10 to 10

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

Recommended value: 2, namely 4dB

OFFSINTERLIGHT (Sintersearch offset 1):

The offset of Sintersearch when center cell load level is "Light“ (Note: Sintersearch is used to decide whether to start the inter-frequency cell reselection).

OFFSINTERHEAVY (Sintersearch offset 2):

The offset of Sintersearch when center cell load level is "Heavy“ (Note: Sintersearch is used to decide whether to start the inter-frequency cell reselection).

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Parameters for PUC (3)

OFFQOFFSET1LIGHT (Qoffset1 offset 1)

Value Range: -20 to 20

Physical Value Range: -20 to 20dB, step 1dB

Recommended value: -4, namely -4dB

OFFQOFFSET2LIGHT (Qoffset2 offset 1)

Value Range: -20 to 20

Physical Value Range: -20 to 20dB, step 1dB

Recommended value: -4, namely -4dB

OFFQOFFSET1LIGHT (Qoffset1 offset 1):

The offset of Qoffset1 when neighboring cell load is lighter than that of center cell (Note: Qoffset1 is used as a priority to decide which cell will be selected while cell selecting or reselecting).

OFFQOFFSET2LIGHT (Qoffset2 offset 1):

The offset of Qoffset2 when neighboring cell load is lighter than that of center cell (Note: Qoffset2 is used as a priority to decide which cell will be selected while cell selecting or reselecting).

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34 Parameters for PUC (4)

OFFQOFFSET1HEAVY (Qoffset1 offset 2)

Value Range: -20 to 20

Physical Value Range: -20 to 20dB, step 1dB

Recommended value: 4, namely 4dB

OFFQOFFSET2HEAVY (Qoffset2 offset 2)

Value Range: -20 to 20

Physical Value Range: -20 to 20dB, step 1dB

Recommended value: 4, namely 4dB

OFFQOFFSET1HEAVY (Qoffset1 offset 2):

The offset of Qoffset1 when neighboring cell load is heavier than that of center cell

OFFQOFFSET2HEAVY (Qoffset2 offset 2):

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1. Load Control Overview

2. Basic Load Control Algorithms

2.1 PUC (Potential User Control)

2.2 CAC (Call Admission Control)

2.3 IAC (Intelligent Admission Control)

2.4 LDR (Load Reshuffling)

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36 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 planed by the Radio Network

Planning

CAC is needed under such scenarios: 1. New call

2. New RAB(s) for ongoing call 3. Handover

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Flow chart of CAC

The admission decision is based on:

• Cell available code resource: managed in RNC

• Cell available power resource: DL/UL load measured in Node B • NodeB resource state, that is, NodeB credits : Reported by Node B • Available Iub transport layer resource, that is, Iub transmission bandwidth:

managed in RNC

• HSDPA user number (only for HSDPA service) • HSUPA user number (only for HSUPA service)

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38 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 thresholds after admission of the new service

For HSDPA services

The code resource admission is not needed

For handover services, the code resource admission is successful if the current remaining code resource is enough for the service.

For other R99 services, RNC shall ensure the remaining code does not exceed the configurable O thresholds after admission of the new service.

For HSDPA services, the reserved codes are shared by all HSDPA services; so the code resource admission is not needed. The RNC adjusts the reserved HS-PDSCH codes according to the real-time usage status of the codes.

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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])

Set this parameter through ADD CELLCAC, query it through LST CELLCAC, and modify it through MOD CELLCAC.

DLHOCECODERESVSF (Dl HandOver Credit and Code Reserved SF):

This parameter is the Downlink Credit and Code Reserved by Spread Factor for Handover service. SFOFF means that none of them are reserved for Handover. If the DL spare resource can not satisfy the reserved resource after the access of a new service, the service will be rejected.

The parameter of [Dl HandOver Credit and Code Reserved SF] must be not less than the either of [Dl LDR Credit SF reserved threshold] and [Cell LDR SF

reserved threshold].

The parameters of [Dl LDR Credit SF reserved threshold] and [Cell LDR SF

reserved threshold] are set in ADD CELLLDR and MOD CELLLDR, and they can be listed by LST CELLLDR.

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40 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 Element 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

When RTWP and/or TCP measurement value are/is invalid/unavailable, the CAC will change from algorithm 1 to 2 automatically.

When measurement are/is valid/available, the CAC will change back to algorithm 1 automatically.

In principle, a request will be admitted only when UL and DL are both admitted. But if UL or DL CAC switch is closed, only one direction CAC also can be realized.

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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 Smaller than N the threshold?

RTWP

P

_N UL

=

1 −

η

∆

η

UL _predicted

=

UL

+

∆

Pn is uplink receive background noise.

The procedure for uplink power resource decision is as follows:

1. The RNC obtains the uplink RTWP of the cell, and calculate the current uplink load factor.

2. The RNC calculates the uplink load increment ΔηUL based on the service request.

3. The RNC uses the formula ηUL,predicted=ηUL + ΔηUL to forecast the uplink load factor.

4. By comparing the forecasted uplink load factor ηUL,predicted with the corresponding threshold (UL threshold of Conv AMR service, UL threshold of Conv non_AMR service, UL threshold of other services, UL Handover access threshold), the RNC decides whether to accept the access request or not.

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42 Downlink CAC Algorithm 1 - Load Prediction

Get current TCP Admission request

Get the traffic characteristic, and estimate the increment of TCP

Calculate the predicted TCP

admitted rejected End of DL CAC Y Smaller than N the threshold?

)

(N

P

∆

P

N

P

(

)

+

∆

The procedure for downlink power resource decision is as follows:

1. The RNC obtains the cell downlink TCP, and calculates the downlink load factor by multiplying the maximum downlink transmit power by this TCP.

2. The RNC calculates the downlink load increment ΔP based on the service request and the current load.

3. The RNC forecasts the downlink load factor.

4. By comparing the downlink load factor with the corresponding threshold (DL threshold of Conv AMR service, DL threshold of Conv non_AMR service, DL threshold of other services, DL Handover access threshold), the RNC decides whether to accept the access request or not.

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Uplink and Downlink CAC Algorithm 2 - ENU

Get current total ENU Admission request

Get the traffic characteristic, and estimate the increment of ENU

Calculate the predicted ENU

admitted rejected

End of UL/DL CAC

Y Smaller than N the threshold?

∑

=

N i i total

N

ENU

1

)

(

new

ENU

new total

total

N

ENU

N

ENU

(

+

1 )

=

(

)

+

max

/

)

1 (

N

ENU

ENULoad

=

_total

+

The ENUmax of DL is very different from the ENUmax of UL. The UL ENUmax is calculated by the system automatically. The DL ENUmax can be configured through parameter:

DL total Non-HSDPA equivalent user number

The procedure for ENU resource decision is as follows: 1. The RNC obtains the total ENU of all exist users ENUtotal. 2. The RNC get the ENU of the new incoming user ENUnew. 3. The RNC forecast the ENU load.

4. By comparing the forecasted ENU load with the corresponding threshold (the same threshold as power resource), the RNC decides whether to accept the access request or not.

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44 Typical equivalent number of users

17.1897 17.0178 3.4 + 384 kbit/s (PS) 11.5245 11.2941 3.4 + 256 kbit/s (PS) 7.1888 6.9731 3.4 + 144 kbit/s (PS) 6.4143 6.2219 3.4 + 128 kbit/s (PS) 3.4188 3.2479 3.4 + 64 kbit/s (PS) 2.2680 2.1319 3.4 + 32 kbit/s (PS) 1.0472 0.9215 3.4 + 16 kbit/s (PS) 0.6325 0.5106 3.4 + 8 kbit/s (PS) 1.3210 0.7662 3.4 + 12.2 kbit/s 1.2131 0.4531 13.6 kbit/s SIG 0.4569 0.2669 3.4 kbit/s SIG

For New Incoming Call For Already Existing Users

Equivalent Number of User (ENU) Service

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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

Set CAC Algorithm Switch through ADD CELLALGOSWITCH, query it through

LST CELLALGOSWITCH, and modify it through MOD CELLALGOSWITCH.

The algorithms the above values represent are as follow:

ALGORITHM_OFF: Disable uplink (or downlink) call admission control algorithm. ALGORITHM_FIRST: The load factor prediction algorithm will be used in uplink (or downlink) CAC.

ALGORITHM_SECOND: The equivalent user number algorithm will be used in uplink (or downlink) CAC.

ALGORITHM_THIRD: The loose call admission control algorithm will be used in uplink (or downlink) CAC.

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46 Parameters for

Load Prediction

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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

Set the following CAC parameters through ADD CELLCAC, query it through LST

CELLCAC, and modify it through MOD CELLCAC.

CELLENVTYPE (Cell environment type):

This parameter is used for Eb/No calculation. you can get the corresponding curves of BLER-Eb/No according the coding mode index and cell environment type index. The curves of BLER-Eb/No with different coding modes and cell environment types are different from each other.

BACKGROUNDNOISE (Background noise):

(47)

Parameters for

Load Prediction

(2)

ULINTERFACTOR (UL neighbor interference factor )

Value Range: 0 to 200

Physical Range: 0 to 2, step: 0.01

Recommended value: 60, namely 0.6

NONORTHOFACTOR (DL Nonorthogonality factor)

Value Range: 0 to 1000

Physical Range: 0 to 1, step: 0.001

Recommended value: 400, namely 0.4

ULINTERFACTOR (UL neighbor interference factor )

This parameter specifies the ratio of UL neighboring cells' interference to this cell's interference.

NONORTHOFACTOR (Nonorthogonality factor):

This parameter is used to predict the transmit power. Zero represents that channels are completely orthogonal and no interference exists between users in DL load factor prediction.

(48)

48 Parameters for Power Resource

Admission (1)

ULCCHLOADFACTOR (UL common channel load factor)

Value range: 0 to 100%

Recommended value: 0, namely 0%

DLCCHLOADRSRVCOEFF (DL common channel load

reserved coefficient)

Value range: 0 to 100%

Recommended value: 0, namely 0%

ULCCHLOADFACTOR (UL common channel load factor):

The CAC is only used for dedicated channels, and for common channels, some resource is reserved. In UL, according to the current load factor and the

characteristics of the new call, the UL CAC algorithm predicts the new traffic channels load factor with the assumption of admitting the new call, then plus with the premeditated common channel UL load factor to get the predicted UL load factor. Then, compare it with UL admission threshold. If it is not higher than the threshold, the call is admitted; otherwise, rejected.

DLCCHLOADRSRVCOEFF (DL common channel load reserved coefficient): This patameter is used for downlink common channel, the effect of this parameter on the network performance is similar with ULCCHLOADFACTOR.

(49)

Parameters for Power Resource

Admission (2)

ULCONVAMRTHD (UL threshold of Conv AMR service)

Value range: 0 to 100%

Recommended value: 75, namely 75%

ULCONVNONAMRTHD (UL threshold of Conv non_AMR

service)

Value range: 0 to 100%

Recommended value: 75, namely 75%

The UL load factor thresholds include this parameter, [UL threshold of Conv AMR service], [UL handover access threshold], and [UL threshold of other services]. The four parameters can be used to limit the proportion between conversational service, handover user and other services in a specific cell, and to guarantee the access priority of conversational service.

ULCONVAMRTHD (UL threshold of Conv AMR service): This parameter is shared by algorithm 1 and algorithm 2.

If this parameter is too high, the system load after admission will probably be too high, which will affect the system stability and result in system congestion;

If it is too low, there will be a bigger probability that users will be rejected, and some resources will be idled and wasted.

ULCONVNONAMRTHD (UL threshold of Conv non_AMR service): This parameter is also shared by algorithm 1 and algorithm 2.

The effect of this parameter on the network performance is similar with ULCONVAMRTHD.

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50 Parameters for Power Resource

Admission (3)

ULOTHERTHD (UL threshold of other services)

Value range: 0 to 100%

Recommended value: 60, namely 60%

ULHOTHD (UL handover access threshold)

Value range: 0 to 100%

Recommended value: 80, namely 80%

ULOTHERTHD (UL threshold of other services):

This parameter is also shared by algorithm 1 and algorithm 2.

ULHOTHD (UL handover access threshold):

Notes:

1. This parameter only applies to inter-frequency handover.

2. This parameter is to reserve resources for handover and to ensure the handover performance; so the value of this parameter must be bigger than uplink threshold for conversation services and smaller than uplink OLC trigger threshold.

Usually, UL handover access threshold>UL threshold of Conversational services>[UL threshold of other services].

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Parameters for Power Resource

Admission (4)

DLCONVAMRTHD (DL threshold of Conv AMR service)

Value range: 0 to 100%

Recommended value: 80, namely 80%

DLCONVNONAMRTHD (DL threshold of Conv non_AMR

service)

Value range: 0 to 100%

Recommended value: 80, namely 80%

The DL load factor thresholds include this parameter, [DL threshold of Conv non_AMR service], [DL handover access threshold], and [DL threshold of other services]. The four parameters can be used to limit the proportion between conversational service, handover user and other services in a specific cell, and to guarantee the access priority of conversational AMR service.

DLCONVAMRTHD (DL threshold of Conv AMR service): This parameter is shared by algorithm 1 and algorithm 2.

If it is too high, the downlink coverage of the cell will be reduced, the neighboring cells will be interfered seriously, and system stability will be affected when cell coverage is very small;

l If it is too low, the system resources will be idled, and the target capacity of the network planning cannot be satisfied.

DLCONVNONAMRTHD (DL threshold of Conv non_AMR service): This parameter is also shared by algorithm 1 and algorithm 2.

The effect of this parameter on the network performance is similar with DLCONVAMRTHD.

(52)

52 Parameters for Power Resource

Admission (5)

DLOTHERTHD (DL threshold of other services)

Value range: 0 to 100%

Recommended value: 75, namely 75%

DLHOTHD (DL handover access threshold)

Value range: 0 to 10%

Recommended value: 85, namely 85%

DLOTHERTHD (DL threshold of other services):

DLHOTHD (DL handover access threshold):

Notes:

1. This parameter only applies to inter-frequency handover.

2. This parameter is to reserve resources for handover and to ensure the handover performance; so the value of this parameter must be bigger than downlink threshold for conversation services and smaller than downlink OLC trigger threshold.

Usually, DL handover access threshold>DL threshold of Conversational services>[DL threshold of other services].

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Parameters for Power Resource

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)

Value range: 1 to 200

Recommended value: 80, namely DL ENUmax = 80

ULTOTALEQUSERNUM (UL total equivalent user number):

When algorithm 2 is used, this parameter defines the total equivalent user number corresponding to the 100% uplink load.

DLTOTALEQUSERNUM (DL total nonhsdpa equivalent user number):

When the algorithm 2 is used, this parameter defines the total equivalent user number corresponding to the 100% downlink load.

(54)

54 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

For handover service, the credit resource admission is successful if the current remaining credit resource is enough for the service.

For other R99 and HSUPA service, RNC shall ensure the remaining credit of the local cell, local cell group (if any), NodeB does not exceed the configurable O&M thresholds (Ul HandOver Credit Reserved SF/ Dl HandOver Credit and Code Reserved SF) after admission of the new service.

(55)

Parameters for Credit Resource

Admission (1)

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])

DLHOCECODERESVSF (Dl HandOver Credit and Code Reserved SF):

This parameter is the Downlink Credit and Code Reserved by Spread Factor for Handover service. SFOFF means that none of them are reserved for Handover. If the DL spare resource can not satisfy the reserved resource after the access of a new service, the service will be rejected.

The parameter of [Dl HandOver Credit and Code Reserved SF] must be not less than the either of [Dl LDR Credit SF reserved threshold] and [Cell LDR SF

reserved threshold].

The parameters of [Dl LDR Credit SF reserved threshold] and [Cell LDR SF

reserved threshold] are set in ADD CELLLDR and MOD CELLLDR, and they can be listed by LST CELLLDR.

(56)

56 Parameters for Credit Resource

Admission (2)

ULHOCERESVSF (Ul HandOver Credit Reserved SF)

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

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

SFOFF

Recommended value: SF16

Configuration Rule and Restriction:

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

threshold

ULHOCERESVSF (Ul HandOver Credit Reserved SF):

This parameter is the Uplink Credit Reserved by Spread Factor for Handover service. SFOFF means that none of them are reserved for Handover.

If the UL spare resource cant safisfy the reserved resource after the acess of a new service, the service will be rejected.

The parameter of [Ul HandOver Credit Reserved SF] must be not less than the

[Ul LDR Credit SF reserved threshold].

The parameter of [Ul LDR Credit SF reserved threshold] is set in ADD CELLLDR and MOD CELLLDR, and they can be listed by LST CELLLDR.

(57)

1. Load Control Overview

2. Basic Load Control Algorithms

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)

(58)

58 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

IAC can increase admission successful rate through the following methods: 1. The data rate of PS service is not fixed, so maybe the cell can admit the UE

after the data rate is decreased.

2. Since the service is non-real time, the users can wait a short time, then access to the cell.

3. The user with high priority can preempt the resource of users with low priority. 4. If the load of neighboring cell is not “Heavy”, UE may be admitted to the

(59)

Flow chart of IAC

(60)

60 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 setup，，，，RAB modify, SRNSR request, reconfiguration

Iu QoS Negotiation (Maximum expected rate negotiation):

In PS domain, CN will negotiate with UE about the access rate. For every service, CN will send a QoS( includes the required data rate) to UTRAN, and UE will report its capability ( the maximum supported rate) to UTRAN. After negotiation, the maximum supported rate of UE will be the maximum negotiation rate.

RAB Downsizing (Initial/target rate negotiation):

To save system resources and improve the admission success rate, BE services does not require access at the maximum expected rate at setup. In stead, a proper rate is adopted for initial access, the rate is smaller than or equal to the maximum expected rate and bigger than or equal to the lowest guarantee rate (usually 8kbps) according to the cell load information. After access, the rate is adjusted higher when the traffic requires and system resources allow it to do so.

The negotiation is based on cell load information, including: •Uplink and downlink radio bearer states of the cell

•Iub resource state

•Minimum spreading factor supported •HSDPA capability

(61)

IAC – Direct Retry based on service

Data service can be retry to HSDPA cells for better QoS

Data service HSDPA CELL A Frequency B R99 CELL2 R99 CELL 1 Frequency A

(62)

62 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

In the service setup, modification, hard handover and transition-in scenarios, if service request supports preempting capability (core network configuration) when application for cell resources fails, preempting will be executed, and the resource of lower-priority user supporting preempting is released to set up the service request. The preemption procedure is as follows:

1.The preemption algorithm determines which radio link sets can be preempted according to the following preemption rules:

- High priority user preempt the resource of low priority users - Preempting the resource of users with low priority first - Preempting single service user first

- Preempting UEs as few as possible, that is, choose the UEs that can release the most resources

- Preempting should follow this sequence: channelization codes first, then Iub transmission resources, radio resources last

2.Release resources occupied by candidate UEs.

3.The requested service uses the released resources to access the network directly without further admission decision.

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IAC – Queuing

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

try to admit again

Queuing priority: P

queue

= T

max

– T

elapsed

T

max

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

T

elapsed

is the time has queued

The queuing algorithm is triggered by poll timer. The specific processing is as follows:

1. Reject this request if the actual wait time of each of the other requests is longer than the maximum queuing time of this request.

2. Calculate the weights of all requests in the queue. The weight: W = (Tmax– Telapsed) / Tmax* Priority Level of the service.

3. Choose the request with the smallest weight to attempt resource allocation. 4. Put it back into the queue with the time stamp unchanged if this request is

rejected.

5. Choose the request with the smallest weight from the rest and performs another attempt until admitting a request or rejecting all requests.

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64 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

If the load of neighboring cell is lighter than current cell, UE may be admitted to the neighboring cell directly.

The RAB DRD procedure is as follows:

1. The RNC determines the admission of the inter-frequency target cell for blind handover.

2. If the admission is accepted, DRD procedure is performed for the inter-frequency target cell for blind handover.

3. The RNC starts the RL setup procedure to complete the inter-frequency hard handover.

4. The RNC starts the RB setup procedure to complete the inter-frequency hard handover on the Uu interface and the service setup.

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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

Set IU_QOS_NEG_SWITCH and RAB_DOWNSIZING_SWITCH through SET

(66)

66 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

Set QUEUEALGOSWITCH and PREEMPTALGOSWITC through SET

(67)

Parameters for RAB Downsizing

ULBETRAFFINITBITRATE (Uplink initial access rates) &

DLBETRAFFINITBITRATE (Downlink 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

Set the parameter through SET FRC, and query it through LST FRC.

When the initial rate selection (RAB Downsizing) function is enabled, this value is the uplink/downlink initial access rate when the BE service is set up. If this rate access fails to satisfy the current load condition, then the actual initial access rate is the negotiated rate based on this rate.

When the RAB Downsizing function is disabled, this parameter is the uplink/downlink initial access rate when the BE service is set up.

The higher this parameter set, the shorter the time fro the BE service to reach the maximum rate but the easier for adjustment downward through negotiation when the system is congested, so it makes no sense to set it too high.

The smaller this parameter, the easier for the BE service to access as per this rate, but, if it is set too low, it will take a longer time to adjust to the required rate when there is a service requirement.

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68 Parameters for Queuing (1)

QUEUELEN (Queue length)

Value range: 5 to 20

Recommended value: 10

POLLTIMERLEN (Poll timer length)

Value range: 1 to 6000

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

Recommended value: 50, namely 500 ms

Set the parameters through SET QUEUEPREEMPT, and query them through LST

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Parameters for Queuing (2)

MAXQUEUETIMELENx (Max queuing time length 1~12)

Value range: 1 to 60s

Recommended value: 5, namely 5 seconds

Set the parameters through SET QUEUEPREEMPT, and query them through LST

(70)

70 Parameters for DRD (1)

DRMAXUMTSNUM (Max inter-frequency direct retry

number)

Value range: 0 to 5

Recommended value: 2

(71)

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

Set the parameter through MOD CELLINETSTRATEGY.

According to the cell type (R99 or R99+HSDPA), an HSDPA user accessing the R99 cell can be DRDed to a R99+HSDPA cell. According to these two parameters, a R99 user accessing the R99+HSDPA cell can be DRDed to a R99 cell.

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72

1. Load Control Overview

2. Basic Load Control Algorithms

2.1 PUC (Potential User Control)

2.2 CAC (Call Admission Control)

2.3 IAC (Intelligent Admission Control)

2.4 LDR (Load Reshuffling)

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LCC (Load Congestion Control)

Overload state: OLC will be used L o a d %

TH

LDR

TH

OLC

100%

section A section B section C 1 ₂

Normal state: Permit entry

Times

Basic congestion state: LDR will be used

LCC (Load Congestion Control) consist of LDR (Load Reshuffling) and OLC (OverLoad Control).

In basic congestion state, LDR will be used to optimize resource distribution, the main rules is not to affect the feeling of users as possible as we can.

In overload state, OLC will be used to release overload state quickly, keep system stability and the service of high priority users.

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74 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

The resources that can trigger the basic congestion of the cell are:

Power resources

If the current UL/DL load of the R99 cell is not lower than UL/DL LDR Trigger threshold (basic congestion control threshold in UL/DL), the cell works in basic congestion state and the related load reshuffling actions are taken.

Code resource

If the current remaining code of the cell is higher than Cell SF reserve threshold, code congestion is triggered and related load reshuffling actions are taken.

Iub resources or Iub bandwidth

Iub congestion control in both the uplink and downlink is NodeB-oriented. Load trigger threshold and load release threshold are set for the uplink and the downlink separately.

Iub congestion control is implemented in a separate process module, so its functionality does not controlled by LDR switchers.

NodeB Credit resource

If the UL/DL current remaining credit resource is higher than Ul Credit SF reserved threshold/ Dl Credit SF reserved threshold, credit congestion is triggered and related load reshuffling actions are taken.

(75)

LDR procedure

Mark "current LDR state = uncongested"

Wait for congestion indication

Congestion

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 of

actions can be

configured

(current action

is taken firstly)

Inter-system handover in CS domain

AMR rate

reduction

Inter-freq

load handover

QoS renogiation

BE rate

reduction

Succeed?

Mark

"current action

= successful

action"

Wait time

for LDR

action duration

Y

N

Inter-system handover in CS domain

Succeed?

Code

reshuffling

Succeed?

Y

N

Y

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76

Different reason will trigger different actions

√

MBMS Power

Reduction

√

Code Reshuffling

√

Iu QoS

Negotiation

√

AMR Rate

Reduction

√

Inter-System

Handover in PS

Domain

√

Inter-system

Handover in CS

Domain

√

BE Rate

Reduction

√

Inter-Frequency

Load Handover

LDR

Actions

DL

UL

DL

UL

DL

UL

UL/DL

Credit

Code

Iub

Power

Resource

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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 hand over to the “Light load” cells

It is implemented as follows:

1. The LDR check whether the existing cell has a target cell of inter-frequency blind handover. If there is no such a target cell, the action fails, and the LDR performs the next action.

2. The LDR checks whether the load difference between the current load and the basic congestion trigger threshold of each target cell for blink handover is larger than UL/DL Inter-freq cell load handover load space threshold (Both uplink and downlink condition must be all fulfilled). If the basic congestion trigger threshold is not set, the admission threshold of the cell is used. If the difference is not larger than the threshold, the action fails. The LDR performs the next action. 3. If the LDR finds out a target cell that meets the specified blind handover

conditions, the LDR selects one UE to make an inter-frequency blind handover, depending on the UE’s integrate priority and occupied bandwidth. The selected UE has lower integrate priority and its bandwidth is less than and has the least difference between the UL/DL Inter-freq cell load handover maximum

bandwidth parameter. If the LDR cannot find such a UE, the action fails. The LDR performs the next action.

Huawei WCDMA Load Control

WCDMA Load Control

2

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

4

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

Soft capacity

6

Uplink Load Definition

Cell Load Factor:

rise

noise

1

1

−

=

η

P

RTWP

rise

noise

=

Downlink Load Definition

8

The Objectives of Load Control

Keeping system stable

Maximizing system capacity while ensuring the coverage and

QoS

Load Control Algorithms

10

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

( )

P

P n

N

=

∑

P

12

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

Parameters for LDM (2)

TENMSECFORULBASICMEAS/TENMSECFORDLBASICMEA

S (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