4 wcdma ran12 load control algorithm and parameters issue1.00

7/22/2019 4 WCDMA RAN12 Load Control Algorithm and Parameters ISSUE1.00

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WCDMA Load Control Algorithm and Parameters

Confidential Information of Huawei. No Spreading Without Permission

N-1


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N-2

The WCDMA system is a self-interfering system. As the load of the system increases,

the interference rises. A relatively high interference can affect the coverage and QoS

of established services. Therefore, the capacity, coverage, and QoS of the WCDMAsystem are mutually affected.

Through the control of key resources, such as power, downlink channelization codes,

channel elements (CEs), Iub transmission resources, which directly affect user

experience, load control aims to maximize the system capacity while ensuring

coverage and QoS.

In addition, load control provides differentiated services for users with different

priorities. For example, when the system resources are insufficient, procedures such

as direct admission, preemption, redirection can be performed to ensure the

successful access of emergency calls to the network.

Load control is implemented in the RNC through measurement reports from theNodeBs.


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WCDMA network load can be defined by four factors:

Power, includes DL transmitting power of cell and increased UL interference

(RTWP)

DL OVSF code of a cell.

DL and UL NodeB processing capability which is defined by NodeB credit.

Iub transmission bandwidth of a NodeB.

The power resource is related to the mobility, distribution of the UE and also effected

by the radio conditions. Therefore, for a fixed power resource, the numbers of service

can be supported is not a fix result. We believe the UL and DL power resources are

soft.


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N-8

In addition, functional load control algorithms vary depending on the load levels of the

cell, as shown in the following figure:

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

Start IAC: increase the access rate in cells with

heavy load by some actions while ensuring the QoS

Start LDR: check and relieve basic congestion in cells

NodeB TX

power (noise)

Cell load (number of subscribers)

Start OLC: check and relieve overload

congestion in cells

Icons for different load levels

Load control

is unneeded


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N-11

The load control functions, such as OLC and CAC, use load measurement values in

the uplink and the downlink. A common Load Measurement (LDM) function is used to

control load measurement in the uplink and the downlink separately.

Load measurement is implemented by the NodeB. The filtering of measurement

quantities is implemented by the NodeB and the RNC.


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The NodeB measures the major quantities related to load control. After layer 3

filtering, the measurement values are reported to the RNC.

The RNC performs smooth filtering on the measurement values reported from the

NodeB and then obtains the measurement values, which further serve as data input

for the load control algorithms.


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N-14

Layer 1 filtering is not standardized by protocols and it depends on vendor equipment.

Layer 3 filtering is standardized. The filtering effect is controlled by a higher layer. The

alpha filtering that applies to layer 3 filtering is calculated according to the followingformula:

Here:

Fn is the new post-filtering measurement value.

Fn-1 is the last post-filtering measurement value.

Mn is the new measurement value from the physical layer.

= (1/2)k/2, where k is specified by the UlBasicCommMeasFilterCoeff orDlBasicCommMeasFilterCoeffparameter.

Set the above parameters through SET ULDM.

PBR measurement does not use alpha filtering on the NodeB side.


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N-15

Set the above parameters through SET ULDM.


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N-16

LDM must apply different smooth filter coefficients and measurement periods to PUC,

CAC, LDR, and OLC so as to obtain appropriate filtered values.

The following table lists the smooth window length parameters for setting different

functions:

GBP measurements have the same smooth window length in all related functions.

The filter length for GBP measurement is specified by the HsdpaNeedPwrFilterLen

parameter.

The length of the PBR smooth filter window is specified by the

HsdpaPrvidBitRateFilterLen / HsupaPrvidBitRateFilterLen parameter.Set the

above parameters through SET ULDM.

Function Smooth Window Length Parameter

PUC PucAvgFilterLen

CACUlCacAvgFilterLen

DlCacAvgFilterLen

LDB LdbAvgFilterLen

LDR UlLdrAvgFilterLenDlLdrAvgFilterLen

OLC UlOlcAvgFilterLen

DlOlcAvgFilterLen


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User priority: mainly applying to provide different QoS for different users. Eg., setting

different GBR according to the user priority for BE service. No consideration about the

service.

RAB integrated priority: priority of a service, related to the service type, and the user

priority of the user.

User integrated priority: only used for multi-RAB user, it is a temporary priority of an

ongoing-service user.


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N-19

In CN HLR, operator can set ARP (Allocation Retention Priority ). During service

setup, CN sends ARP to RNC. Based on the mapping relation (configured in RNC),

RNC can identify the users priority, namely gold, silver or copper one.


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N-20

User priorities are adopted to provide differentiated services for users. For ease of

application, the RNC maps the 15 levels of Allocation/Retention Priority (ARP) that is

carried in the RAB ASSIGNMENT REQUEST message from the core network (CN)onto three user priorities, that is, gold (high priority), silver (medium priority), and

copper (low priority). The relation between user priority and ARP can be set through

SET UUSERPRIORITY command.

ARP 15 is always the lowest priority and is not configurable. It corresponds to lowest

user priority (copper user).

If ARP is not received in messages from the Iu interface, the user priority is regarded

as copper.


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The priority of a RAB is determined by its traffic class, ARP, and carrier type. Such a priority is

called RAB integrated priority. When resources are insufficient, services with the highest

integrated priority are preferentially processed. The values of RAB integrated priority are set according to the integrated priority configuration

reference parameter (PriorityReference):

If PriorityReference is set to Traffic Class, the integrated priority abides by the

following rules:

Traffic classes: conversational > streaming > interactive > background

Services of the same traffic class: priority based on ARP, that is, ARP1 >

ARP2 > ARP3 > ... > ARP14 > ARP15

Service of the same traffic class and ARP (only for interactive services):

priority based on Traffic Handling Priority (THP) that is carried in the RAB

ASSIGNMENT REQUEST message, that is, THP1 > THP2 > THP3 > ... >

THP14 > THP15

Services of the same traffic class, ARP and THP (only for interactive services):

High Speed Packet Access (HSPA) or Dedicated Channel (DCH) service

preferred depending on CarrierTypePriorInd.

If PriorityReference is set to ARP, the integrated priority abides by the following rules:

ARP: ARP1 > ARP2 > ARP3 > ... > ARP14 >ARP15

Services of the same ARP: priority based on traffic classes, that is,

conversational > streaming > interactive > background

Only for the interactive service of the same ARP value: priority based onTraffic Handling Priority (THP), that is, THP1 > THP2 > THP3 > ... > THP14 >

THP15

Services of the same ARP, traffic class and THP (only for interactive services):

HSPA or DCH service preferred depending on CarrierTypePriorInd.


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This example shows the RAB integrated priority calculation in 2 different conditions.


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A user may have multiple RABs, and the RABs may have different priorities. In this

case, the highest priority is taken as the priority of this user. Such a priority is called

user integrated priority. User integrated priority is used in user-specific load control.For example, the selection of R99 users during preemption, the selection of users

during inter-frequency load handover for LDR, and the selection of users during

switching of BE services to common channels are performed according to the user

integrated priority.


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Prior i tyReference

Content: Reference used to determine which priority is arranged first in the

priority sequence. If the ARP is preferably used, the priority sequence is gold >

silver > copper. If the ARPs are all the same, the TrafficClass is used and the

priority sequence is conversational > streaming > interactive > background.

If the TrafficClass is preferably used, the priority sequence is conversational >

streaming > interactive > background. If the TrafficClass factors are all the

same, the ARP factor is used and the priority sequence is gold > silver >

copper.

Value range: ARP, TrafficClass

Physical value range: ARP, TrafficClass

CarrierTypePriorInd

Content: Decide which carrier is prior when ARP and TrafficClass are both

identical.

Value range: NONE, DCH, HSPA

Physical value range: NONE, DCH, HSPA

Set these parameters through SET UUSERPRIORITY.


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N-26

The Potential User Control (PUC) function controls the cell reselection of a UE that is

in idle mode, or in the CELL_FACH state, CELL_PCH state, or URA_PCH state and

prevents the UE from camping on a heavily loaded cell.

PUC procedure:

Adjust the parameters of the

current cell and neighboring cellsaccording to the load

YesNo

Update and broadcast the system

information of the current cell andneighboring cells

Periodically monitor the load of the

current cell and neighboring cells

Are these

parameters changed?


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N-27

The PUC function is enabled only when the PUC subparameter of the

NBMLdcAlgoSwitch parameter is set to 1. Set the NBMLdcAlgoSwitch parameter

through ADD UCELLALGOSWITCH/ MOD UCELLALGOSWITCH.


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The load state of a cell supporting DC-HSDPA is determined based on the following

table:Load of Single

Cell Load of Cell Group Load of Cell Supporting DC-HSDPA

Heavy Heavy, normal, or light Heavy

Heavy, normal, or

light

Heavy Heavy

Normal Normal, or light Normal

Normal, or light Normal Normal

Light Light Light


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N-30

Based on the cell load, the PUC works as follows:

If the cell load becomes heavy, the PUC modifies reselection parameters and

broadcasts them through system information. In this way, the PUC leads UEs

to the neighboring cells with light load.

If the cell load becomes normal, the PUC uses the reselection parameters

configured on the RNC LMT.

If the cell load becomes light, the PUC modifies cell reselection parameters

and broadcasts them through system information. In this way, the PUC leads

UEs to this cell.


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The variables related to cell selection and reselection are Qoffset1(s,n) (load level

offset), Qoffset2(s,n) (load level offset), and Sintersearch (start threshold for inter-

frequency cell reselection). The following table describes PUC-related variables and

their impacts on UEs:Item Description

Implementatio

n

The variables related to cell selection and reselection areQoffset1(s,n) (load level offset), Qoffset2(s,n) (load level

offset), and Sintersearch (start threshold for inter-frequency

cell reselection).

The NodeB periodically reports the transmit power of the cell,

and the PUC periodically triggers the following activities:

Assessing the cell load level based on the non-HSPA power

and HS-DSCH GBP

Setting Sintersearch, Qoffset1(s,n), and Qoffset2(s,n) based

on the cell load level

Updating the parameters in system information SIB3 andSIB11

Adjustment

Based on the characteristics of inter-frequency cell selection

and reselection, the UE makes the corresponding adjustments:

Sintersearch

- When this value is increased by the serving cell, the UE

starts inter-frequency cell reselection ahead of schedule.

- When this value is decreased by the serving cell, the UE

delays inter-frequency cell reselection.

Qoffset1(s,n): applies to R (reselection) rule with CPICH

RSCP- When this value is increased by the serving cell, the UE has

a lower probability of selecting a neighboring cell.

- When this value is decreased by the serving cell, the UE has

a higher probability of selecting a neighboring cell.

Qoffset2(s,n): applies to R (reselection) rule with CPICH

Ec/No

- When this value is increased by the serving cell, the UE has

a lower probability of selecting a neighboring cell.

- When this value is decreased by the serving cell, the UE has

a higher probability of selecting a neighboring cell.


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Depending on the load status of the serving cell, the cell reselection parameters are

adjusted up or down or kept unchanged. The setting of Sintersearch is related to the

serving cell:

Load State of the

Serving Cell Sintersearch

Change to

Sintersearch

Light S'intersearch = Sintersearch + OffSinterLight

Normal S'intersearch = Sintersearch

Heavy S'intersearch = Sintersearch + OffSinterHeavy

: indicates that the parameter value remains unchanged.: indicates that the parameter value increases.

: indicates that the parameter value decreases.


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The configurations of Qoffset1 and Qoffset are related to the load of the serving cell

and the load of the neighboring cells:

Load State

of the

Neighboring

Cells

Load State

of the

Serving

Cell

Q'offset1

Change

to

Q'offset1

Q'offset2

Change

to

Q'offset2

Light Light Q'offset1 = Qoffset1 Q'offset2 = Qoffset2

Light Normal Q'offset1 = Qoffset1 Q'offset2 = Qoffset2

Light HeavyQ'offset1 = Qoffset1

+ OffQoffset1Light

Q'offset2 = Qoffset2

+ OffQoffset2Light

Normal Light Q'offset1 = Qoffset1 Q'offset2 = Qoffset2

Normal Normal Q'offset1 = Qoffset1 Q'offset2 = Qoffset2

Normal Heavy


+ OffQoffset1Light


+ OffQoffset2Light

Heavy LightQ'offset1 = Qoffset1

+ OffQoffset1Heavy


+ OffQoffset2Heavy

Heavy NormalQ'offset1 = Qoffset1

+ OffQoffset1Heavy


+ OffQoffset2Heavy

Heavy Heavy Q'offset1 = Qoffset1 Q'offset2 = Qoffset2


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NBMLdcAlgoSwitch-PUC

Content: Potential user control algorithm. Based on the cell load, this algorithm

changes the selection/reselection parameters of a cell to lead the UE to a

lighter loaded cell.

Value range: OFF, ON

Physical value range: 0, 1

Set this parameter through ADD UCELLALGOSWITCH/ MOD

UCELLALGOSWITCH.

SpucHeavy/SpucLight

Content: It is used to decide whether the cell load level is Heavy or Light. It is

denoted by the ratio of NodeB TX power to the maximum TX power.

Value range: 0~100

Physical value range: 0~100; step: 1

Physical unit: %

Set this parameter through ADD UCELLPUC/ MOD UCELLPUC.


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SpucHyst

Content: Hysteresis used to determine the cell load level. It is denoted by the

ratio of NodeB TX power to the maximum TX power. It is used to avoid the

unnecessary ping-pong effect of a cell between two load levels due to tiny

load change.

Value range: 0~100


Physical unit: %

Set this parameter through ADD UCELLPUC/ MOD UCELLPUC.

PucPer iodTimerLen

Content: Identifying the potential user control period. When the cell load is

high, the cell selection and reselection can be periodically modified in order toenable users in unconnected mode to select other cells more easily, thus

reducing the local cell load.

Value range: 6~86400


Physical unit: s

Set this parameter through SET ULDCPERIOD.


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OffSinter ight

Content: Offset of Sintersearch when center cell load level is "Light.

Value range: -10~10

Physical value range: -10~10; step: 2

Physical unit: dB

OffSinterHeavy

Content: Offset of Sintersearch when center cell load level is Heavy.

Value range: -10~10


Physical unit: dB

Set these parameters through ADD UCELLPUC/ MOD UCELLPUC.


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OffQoffset1Light

Content: Offset of Qoffset1 when neighboring cell load is lighter than that of

the center cell.

Value range: -20~20


Physical unit: dB

OffSinterHeavy

Content: Offset of Qoffset1 when neighboring cell load is heavier than that of

the center cell.

Value range: -20~20

Physical value range: -20~20; step: 1 Physical unit: dB



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OffQoffset2Light

Content: Offset of Qoffset2 when neighboring cell load is lighter than that of

the center cell.

Value range: -20~20


Physical unit: dB

OffQoffset2Heavy

Content: Offset of Qoffset2 when neighboring cell load is heavier than that of

the center cell.

Value range: -20~20

Physical value range: -20~20; step: 1 Physical unit: dB



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Intra-frequency Load Balancing (LDB) is performed to adjust the coverage areas of

cells according to the measured values of cell load. The intra-frequency LDB function

is applicable only to the downlink.

LDB between intra-frequency cells is implemented by adjusting the transmit power of

the Primary Common Pilot Channel (PCPICH) according to the downlink load of the

associated cells. When the load of a cell increases, the cell reduces its coverage to

lighten its load. When the load of a cell decreases, the cell extends its coverage so

that some traffic is off-loaded from its neighboring cells to it.


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When the intra-frequency LDB function is active, that is, when the

INTRA_FREQUENCY_LDB subparameter of the NBMLdcAlgoSwitch parameter is

set to 1, the RNC checks the load of cells periodically and adjusts the transmit powerof the P-CPICH in the associated cells based on the cell load. Set the

NBMLdcAlgoSwitch parameter through ADD UCELLALGOSWITCH/ MOD

UCELLALGOSWITCH.

The intra-frequency LDB is described as follows:

If the downlink load of a cell is higher than the cell overload threshold

(CellOverrunThd), it is an indication that the cell is heavily overloaded. In this

case, the transmit power of the P-CPICH needs to be reduced step by step.

The step is specified by the PCPICHPowerPace parameter.

If the current transmit power is equal to the minimum transmit power of P-

CPICH (MinPCPICHPower), the current transmit power is not adjusted.

If the downlink load of a cell is lower than the cell underload threshold

(CellUnderrunThd), it is an indication that the cell has sufficient remaining

capacity for more load. In this case, the transmit power of the P-CPICH can be

increased step by step to help lighten the load of neighboring cells. The step is

specified by the PCPICHPowerPace parameter.

If the current transmit power is equal to the maximum transmit power of P-

CPICH (MaxPCPICHPower), the current transmit power is not adjusted.


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NBMLdcAlgoSwitch-INTRA_FREQUENCY_LDB

Content: Intra-frequency load balance algorithm. It is also named cell

breathing algorithm. Based on the cell load, this algorithm changes the pilot

power of the cell to control the load between intra-frequency cells.



Set this parameter through ADD UCELLALGOSWITCH/ MOD

UCELLALGOSWITCH.

IntraFreqLdbPer iodTimerLen

Content: Identifying the period of the Intra-frequency load balance algorithm.

When the cell load is high, the cell PCPICH TX power can be periodically

reduced in order to enable users in connected mode to be switched over to

other cells more easily, thus reducing the local cell load.



Physical unit: s

Set this parameter through SET ULDCPERIOD.


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CellOverrunThd

Content: If the cell downlink load exceeds this threshold, the algorithm will decrease the pilot

transmit power of the cell so as to increase the whole system's capacity. This parameter isbased on network planning. When the cell breathing algorithm is activated, if the value is too

small, the physical coverage of the cell is limited so as to avoid cell capacity waste. If the value

is too great, the physical coverage is expanded and interference over other cells is increased.

Value range: 0~100


Physical unit: %

Cel lUnderrunThd

Content: If the cell downlink load is lower than this threshold, the algorithm will increase the pilot

transmit power of the cell so as to share load of other cells. This parameter is based on network

planning. When the cell breathing algorithm is activated, if the value is too small, the physical

coverage of the cell is limited so as to avoid cell capacity waste. If the value is too great, thephysical coverage is expanded and interference over other cells is increased.

Value range: 0~100


Physical unit: %

PCPICHPowerPace

Content: Pilot power adjustment step increased or decreased in each increase of the cell

breathing algorithm or decrease of cell pilot. If the value is too great, the cell pilot may change

fiercely, which is easy to lead to user call drops. If the value is too small, the cell pilot may

change smoothly. However, the response speed of the cell breathing algorithm is decreased,

impacting the algorithm performance.

Value range: 0~100

Physical value range: 0~10; step: 0.1

Physical unit: dB

Set these parameters through ADD UCELLLDB/ MOD UCELLLDB.


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PCPICHPower

Content: TX power of the PCPICH in a cell.

Value range: -100~500

Physical value range: -10~50; step: 0.1

Physical unit: dBm

MaxPCPICHPower

Content: Maximum TX power of the PCPICH in a cell.



Physical unit: dBm

MinPCPICHPower

Content: Minimum TX power of the PCPICH in a cell.



Physical unit: dBm

Set these parameters through ADD UPCPICH/ MOD UPCPICHPWR.


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N-47

CAC is needed under such scenarios:

RRC connection setup request

RAB admission decision

Handover

Rate reconfiguration


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N-48

The admission decision is based on:

Available cell code resource

Available cell power resource

NodeB credits, which are used to measure the channel demodulation

capability of NodeBs

Available Iub transmission bandwidth

Number of HSDPA users (only for HSDPA services)

Number of HSUPA users (only for HSUPA services)

A call can be admitted only when all of these resources are available.


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N-49

Code and Iub resource-based admission control are mandatory and can not be disabled. Other

admission control strategies may be enabled/disabled through the RNC command:

The switch of power CAC can be set by ADD UCELLALGOSWITCH/ MODUCELLALGOSWITCH:

Uplink CAC algorithm switch (NBMUlCacAlgoSelSwitch) selects the algorithm

used for power admission in the uplink.

Downlink CAC algorithm switch (NBMDlCacAlgoSelSwitch) selects the

algorithm used for power admission in the downlink.

The switch of NodeB credit CAC can be set by SET UCACALGOSWITCH and ADD

UCELLALGOSWITCH/ MOD UCELLALGOSWITCH:

CAC algorithm switch (CacSwitch) specifies whether to enable or disable the

NodeB level credit CAC algorithm.

Cell CAC algorithm switch (CRD_ADCTRL) specifies whether to enable or

disable the cell level credit CAC algorithm.

The switch of HSDPA user number CAC can be set by ADD UCELLALGOSWITCH/

MOD UCELLALGOSWITCH:

Cell CAC algorithm switch (HSDPA_UU_ADCTRL) specifies whether to

enable or disable the HSDPA user number admission control algorithm.

The switch of HSUPA user number CAC can be set by ADD UCELLALGOSWITCH/

MOD UCELLALGOSWITCH:

Cell CAC algorithm switch (HSUPA_UU_ADCTRL) specifies whether to

enable or disable the HSUPA user number admission control algorithm.


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N-51

When a new service attempts to access the network, code resource-based admission

is mandatory.

Code resourcebased admission is implemented as follows:

For RRC connection setup requests, the code resource-based admission is

successful if the current remaining code resource is sufficient for RRC

connection setup.

For handover services, the code resource-based admission is successful if the

current remaining code resource is sufficient for the service.

For other R99 services, the RNC has to ensure that the remaining code does

not exceed the DlHoCeCodeResvSfparameter after admission of the new

service.

For HSDPA services, the reserved codes are shared by all HSDPA services.Therefore, the code resource-based admission is not required.


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N-52

DlHoCeCodeResvSf

Content: Some cell resources can be reserved for handover UEs to guarantee

handover success rate and improve access priority of handover services. This

parameter defines the quantity of downlink code and CE resources reserved

for handover. SFOFF refers to that no resources is reserved. SF32 refers to

that a code resource with SF = 32 and its corresponding credit resource are

reserved. The backer position the value is in {SF4, SF8, SF16, SF32, SF64,

SF128, SF256, SFOFF}, the less code and credit resources reserved for

handover UEs. The possibility of rejecting handover UE admissions increases

and performance of UEs cannot be guaranteed. The more frontal position the

value is, the more the possibility of rejecting new UEs is and some idle

resources are wasted.

Value range: SF4, SF8, SF16, SF32, SF64, SF128, SF256, SFOFF Physical value range: SF4, SF8, SF16, SF32, SF64, SF128, SF256, SFOFF

Set this parameter through ADD UCELLCAC/ MOD UCELLCAC.


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N-54

The principles of NodeB credit-admission control are similar to those of power-based

admission control, that is, to check in the local cell, local cell group (if any), and

NodeB whether the remaining credit can support the requesting services.

The CE capabilities at the levels of local cell, local cell group, and NodeB are reported

to the RNC through the NBAP_AUDIT_RSP message over the Iub interface.

The CE capability of local cell level indicates the maximum capability in terms

of hardware that can be used in the local cell.

The CE capability of local cell group level indicates the capability obtained

after the license and hardware are taken into consideration.

The CE capability of NodeB level indicates the number of CEs allowed to use

as specified in the license.

For details about local cell, local cell group, and capacity consumption law,refer to the 3GPP TS 25.433.

According to the capacity consumption laws of common and dedicated channels, the

Controlling RNC (CRNC) debits the amount of the credit resource consumed from or

credits the amount to the Capacity Credit (CC) of the local cell (or local cell group, if

any) based on the SF. The specific scenarios are the addition, removal, and

reconfiguration of the common and dedicated channels.

If the UL CC and the DL CC are separate, they are maintained separately in

the local cell or local cell group.

If the UL CC and DL CC are not separate, only the total CC is maintained in

the local cell or local cell group.


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N-55

For the DCH service, the RNC uses the MBR to calculate the SF and searches the

following table for the number of consumed CEs.

Direction Rate

(kbit/s)

SF Number of CEs

Consumed

Corresponding Credits

Consumed

UL 3.4 256 1 2

13.6 64 1 2

8 64 1 2

16 64 1 2

32 32 1.5 3

64 16 3 6

128 8 5 10

144 8 5 10

256 4 10 20

384 4 10 20

DL 3.4 256 1 1

13.6 128 1 1

8 128 1 1

16 128 1 1

32 64 1 1

64 32 2 2

128 16 4 4

144 16 4 4

256 8 8 8

384 8 8 8


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N-56

For the HSUPA service,

If the NodeB reports through its private interface that the dynamic CE function

of the cell is enabled, the RNC uses the GBR to calculate the SF.

If the NodeB reports that the dynamic CE function is disabled, the RNC uses

the MBR to calculate the SF. If the NodeB does not report whether the dynamic CE function is enabled, the

RNC determines whether to use the GBR or MBR to calculate the spreading

factor, based on the value of HsupaCeConsumeSelection.

Direction Rate

(kbit/s)

SF Number of CEs

Consumed

Corresponding Credits

Consumed

UL 8 64 1 2

16 64 1 2

32 32 1 2

64 32 1 2

128 16 2 4

144 16 2 4

256 8 4 8

384 4 8 16

608 4 8 16

1450 2SF4 16 32

2048 2SF2 32 64

2890 2SF2 32 64

5760 2SF2+2SF4 48 96


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N-57

When a new service tries to access the network, the admission decision based on

NodeB credit is implemented as follows:

For an RRC connection setup request, the credit resource-based admission is

successful if the current remaining credit resources of the local cell, local cell

group (if any), and NodeB are sufficient for RRC connection setup.

For a handover service, the credit resource-based admission is successful if

the current remaining credit resources of the local cell, local cell group (if any),

and NodeB are sufficient for the service.

For other services, the RNC has to ensure that the remaining credit of the

local cell, local cell group (if any), and NodeB does not exceed the value of

UlHoCeResvSf(for the uplink) or DlHoCeCodeResvSf(for the downlink) after

admission of the new services.


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N-58

UlHoCeResvSf

Content: Uplink Credit Reserved by Spread Factor for HandOver. SFOFF means that none ofthem are reserved for handover. If the UL spare resource cant satisfy the reserved resourceafter the access of a new service, the service will be rejected. If the value is too high, the creditresource reserved for handover UEs will be less, leading to the increased possibility of rejectinghandover UE admissions, and performance of handover UEs cannot be guaranteed. If the valueis too low, the possibility of rejecting new UEs may increase and some idle resources arewasted.

Value range: SF4, SF8, SF16, SF32, SF64, SF128, SF256, SFOFF

Physical value range: SF4, SF8, SF16, SF32, SF64, SF128, SF256, SFOFF


DlHoCeCodeResvSf

Content: Some cell resources can be reserved for handover UEs to guarantee handoversuccess rate and improve access priority of handover services. This parameter defines thequantity of downlink code and CE resources reserved for handover. SFOFF refers to that no

resources is reserved. SF32 refers to that a code resource with SF = 32 and its correspondingcredit resource are reserved. The backer position the value is in {SF4, SF8, SF16, SF32, SF64,SF128, SF256, SFOFF}, the less code and credit resources reserved for handover UEs. Thepossibility of rejecting handover UE admissions increases and performance of UEs cannot beguaranteed. The more frontal position the value is, the more the possibility of rejecting new UEsis and some idle resources are wasted.

Value range: SF4, SF8, SF16, SF32, SF64, SF128, SF256, SFOFF

Physical value range: SF4, SF8, SF16, SF32, SF64, SF128, SF256, SFOFF


HsupaCeConsumeSelect ion

Content: When the dynamic CE algorithm on NodeB is applied, the CE consumption of HSUPAUE is based on the GBR. When the dynamic CE algorithm on NodeB is not applied, the CEconsumption of HSUPA UE is based on the MBR. If the CE consumption of HSUPA UE is

based on the GBR, the CE LDR will not select HSUPA users to do data rate reduction. If the CEconsumption of HSUPA UE is based on the MBR,the CE LDR will select HSUPA users to dodata rate reduction on condition that the HSUPA DCCC switch is ON.

Value range: MBR, GBR

Physical value range: MBR, GBR

Set this parameter through ADD UNODEBALGOPARA/ MOD UNODEBALGOPARA.


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N-59


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N-60

The Universal Mobile Telecommunications System (UMTS) supports four traffic

classes: conversational, streaming, interactive, and background. The transmission

rate varies with the traffic class as follows:

For Circuit Switched (CS) conversational services, the channel transmits

voice signals at a certain rate (for example, 12.2 kbit/s) during a conversation

and only transmits Silence Descriptors (SIDs) at intervals when there is no

conversation.

For Packet Switched (PS) interactive and background services, such as web

browsing, there is data transmitted during data downloading. After a web

page has been downloaded, and when the user is reading the page, however,

there is very little data to transfer.

If the Radio Network Controller (RNC) allocates the maximum bandwidth to the

subscriber when a service is established, a large proportion of the Iub transmissionbandwidth is unused. For example, downloading a 50 KB page takes only about one

second, but reading this page needs dozens of seconds. Thus, over 90% of the Iub

transmission bandwidth is not used.

To save the Iub transmission bandwidth for operator use, Huawei provides the Iub

overbooking function, which applies an admission control mechanism to access the

service. Services are admitted according to the different activity factors. PS

interactive and background services can be admitted according to the Guaranteed Bit

Rate (GBR). In this way, the maximum number of users with the minimum number of

activity request to use voice and PS Best Effort (BE) services can access the network,

thus achieving a better utilization of transmission bandwidth.


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N-61

For BE services, the GBR can be set by running the SET UUSERGBR command.

Activity factors can be configured for different types of service by running the ADD

TRMFACTOR/ MOD TRMFACTOR command.

Default settings of activity factors for typical types of service:

Type of Service Default Activity Factor (%)

SRB 15/15 (DL/UL)

AMR voice 70/70 (DL/UL)

R99 CS streaming 100/100 (DL/UL)

R99 PS conversational 70/70 (DL/UL)

R99 PS streaming 100/100 (DL/UL)

R99 PS interactive 100/100 (DL/UL)

R99 PS background 100/100 (DL/UL)

HSPA SRB 50/50 (DL/UL)

HSPA voice 70/70 (DL/UL)

HSPA conversational 70/70 (DL/UL)

HSPA streaming 100/100 (DL/UL)

HSPA interactive 100/100 (DL/UL)

HSPA background 100/100 (DL/UL)


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N-62

The parameters of threshold should satisfy with: Bandwidth reserved for handover Congestion threshold Congestion resolving threshold.

The congestion threshold and the congestion resolving threshold are used to prevent

the ping-pong effect.

Based on the preceding requirement, the user priorities are as follows:

User requesting handover > New user > User requesting rate upsizing

The congestion thresholds are FWDCONGBWand BWDCONGBW, and the

congestion resolving thresholds are FWDCONGCLRBWand BWDCONGCLRBW.

The parameters that are used to reserve bandwidth for handover are as follows:

FWDHORSVBW

BWDHORSVBW


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N-63

The admission procedure is as follows:

The new user attempts to be admitted to available bandwidth 1 on the primary path.

If the user succeeds in applying for the resources on the primary path, the user is

admitted to the primary path.

If the user fails to apply for the resources on the primary path, the user then attempts

to be admitted to available bandwidth 2 on the secondary path. If the user succeeds in applying for the resources on the secondary path, the user is

admitted to the secondary path. If the user fails, the bandwidth admission request of

the user is rejected.

Admission procedure for handover of a user:

Admission procedure for a new user:

Admission procedure for rate upsizing of a user:


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N-64

FWDHORSVBW/BWDHORSVBW

Content: Reserved forward/backward bandwidth for handover user .


Physical value range:0~320000; step: 1

Physical unit: Kbit/s

FWDCONGBW/BWDCONGBW

Content: If the available forward/backward bandwidth is less than or equal to

this value, the forward/backward congestion alarm is emitted.



Physical unit: Kbit/s FWDCONGCLRBW/BWDCONGCLRBW

Content: If the available forward/backward bandwidth is greater than this value,

the forward/backward congestion alarm is cleared.



Physical unit: Kbit/s

Set these parameters through ADD AAL2PATH/ MOD AAL2PATH (for ATM

networking) and ADD IPPATH/ MOD IPPATH (for IP networking).


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N-69

MaxHsdpaUserNum

Content: Maximum number of users supported by the HSDPA channel. The

user in this parameter refers to the user with services on the HSDPA channel,

regardless of the number of RABs carried on the HSDPA channel. Maximum

HSDPA user number cannot exceed the HSDPA capability of the NodeB

product, In practice, the value can be set based on the cell type and the

richness of the available HSDPA power and code resources. If the value is too

low, the cell HSDPA capacity may be reduces, leading to waste in HSDPA

resources. If the value is too high, HSDPA services may be congested.

Value range: 0~100



NodeBHsdpaMaxUserNum

Content: Maximum number of HSDPA users of the NodeB.

Value range: 0~3840


Set this parameter through ADD UNODEBALGOPARA/ MOD

UNODEBALGOPARA.


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N-70

MaxHsupaUserNum

Content: Maximum number of users supported by the HSUPA channel. The

user in this parameter refers to the user with services on the HSUPA channel,

regardless of the number of RABs carried on the HSUPA channel. Maximum

HSUPA user number cannot exceed the HSUPA capability of the NodeB

product, In practice, the value can be set based on the cell type and the

richness of the available HSUPA power and code resources. If the value is too

low, the cell HSDPA capacity may be reduces, leading to waste in HSUPA

resources. If the value is too high, HSUPA services may be congested.

Value range: 0~100



NodeBHsupaMaxUserNum

Content: Maximum number of HSUPA users of the NodeB.

Value range: 0~3840


Set this parameter through ADD UNODEBALGOPARA/ MOD

UNODEBALGOPARA.


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N-72

The purpose of Intelligent Access Control (IAC) is to increase the access success rate,

that is, RRC connection success rate and RAB setup success rate.


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N-73

There are two types of IAC, IAC for RRC connection processing and IAC for RAB

processing:

IAC for RRC connection processing is used to select a suitable cell for a UE to

access through redirection and RRC DRD. It also implements load balancing

and service steering

IAC for RAB processing is used to select a suitable cell for a UE to access

through DRD and CAC. It also implements load balancing and service steering.

Preemption, queuing, and low-rate access are used to further improve the

RAB setup success rate

IAC procedure supported by services:

Service

Type

Low-

Rate

Access

Rate Negotiation

Preemption Queuing

DRD

MBR

Negotiation

GBR

Negotiation

InitialRate

Negotiation

TargetRate

Negotiation

Inter-

Frequency

Inter-RAT

DCH

HSUPA

HSDPA


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N-74

As shown in the previous figure, the procedure of service access includes the

procedures for RRC connection setup and RAB setup. The successful setup of the

RRC connection is one of the prerequisites for the RAB setup.

During the RRC connection processing, the RNC performs the following steps:

1. Performs the RRC redirection based on distance (only for UE-originating

AMR services). If the RNC decides UE access from another cell, it sends anRRC connection reject message to the UE; otherwise, the RNC performs the

next step.

2. Performs RRC redirection for service steering.

3. If the RNC decides UE access from the current cell, it then makes a

resource-based admission decision. If the resource-based admission fails, the

RNC performs directed retry decision (DRD) and redirection.

If the RNC decides UE access from the current cell, it then makes a resource-

based admission decision. If the resource-based admission fails, the RNC

performs directed retry decision (DRD) and redirection.

If the RNC decides UE access from another cell, it then sends an RRC

connection reject message to the UE. The message carries the information

about the cell and instructs the UE to set up an RRC connection to the cell.

During the RAB processing, the RNC performs the following steps:

1. Performs inter-frequency DRD to select a suitable cell for service steering or

load balancing.

2. Performs rate negotiation according to the service requested by the UE.

3. Makes cell resource-based admission decision. If the admission is successful,

UE access is granted. Otherwise, the RNC performs the next step.

4. Selects a suitable cell, according to the inter-frequency DRD algorithm, fromthe cells where no admission attempt has been made, and then goes to 2. If

the attempt fails, the RNC performs the next step.

5. Selects a suitable cell, according to the inter-RAT DRD algorithm. If the inter-

RAT admission is successful, UE access is granted in the inter-RAT cell. If

the inter-RAT DRD fails or is not supported, the RNC performs the next step.

6. Makes a preemption attempt. If the preemption is successful, UE access is

granted. If the preemption fails or is not supported, the RNC performs the next

step.

7. Makes a queuing attempt. If the queuing is successful, UE access is granted.

If the queuing fails or is not supported, the RNC performs the next step.

8. Performs low-rate access. If the low-rate access is admitted, UE access is

granted. If the low-rate access is unsuccessful, the RNC performs the next

step.

9. Rejects UE access.


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N-76

IAC RRC Connection Setup


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N-77

Before a new service is admitted to the network, an RRC connection must be set up.

After receiving an RRC CONNECTION REQUEST message from the UE, the RNC

performs the RRC redirection based on distance (only for UE-originating AMR

services). For details, see section 5.2.2 "RRC Redirection based on Distance". If the

RNC decides UE access from another cell, it sends an RRC connection reject

message to the UE; otherwise, the RNC performs the next step. Then, the RNC uses the RRC redirection algorithm for service steering to decide

whether the UE may access the network from the current cell:

If the UE can access the network from the current cell according to the

decision result, the RNC uses the CAC algorithm to decide whether an RRC

connection can be set up between the UE and the current cell.

If the RRC connection can be set up between the UE and the current

cell, the RNC sends an RRC CONNECTION SETUP message to the

UE.

If the RRC connection cannot be set up between the UE and thecurrent cell, the RNC attempts to select a cell for RRC connection

setup through RRC DRD. If the RRC DRD fails, RRC redirection will be

performed.

If the UE needs to access the network from another cell according to the

decision result, the RNC sends an RRC CONNECTION REJECT message to

the UE. The message carries the information about this cell.


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N-78

In actual situations, a UE may receive signals from a distant cell and subsequently access thecell. However, the cells that are adjacent to this cell are not configured as its neighboring cells.

If the UE moves out of this cell, call drops may occur. To solve this problem, RRC redirectionbased on distance is introduced.

The procedure of RRC redirection based on distance is as follows:

1. Upon receiving an RRC CONNECTION REQUEST message from the UE, the RNCdetermines whether the requested service is the UE-originating AMR service. If yes, the RNCperforms the next step. If no, the RNC does not perform RRC redirection based on distance,and handles the RRC connection setup request of the UE in the current cell.

2. The RNC obtains the propagation delay from the NodeB and compares it with DelayThs.

If the propagation delay is greater than DelayThs, the RNC performs the next step.

If the propagation delay is equal to or smaller than DelayThs, the RNC does notperform RRC redirection based on distance, and handles the RRC connection setuprequest of the UE in the current cell.

3. The RNC checks the load status of the current cell and determines whether to perform RRCredirection based on distance by considering the load status.

If the cell is in the normal state, the RNC generates a random value ranging from 0 to 1and compares the value with the parameter RedirFactorOfNorm. If the random value isequal to or smaller than the parameter, the RNC performs the next step. Otherwise,the RNC does not perform RRC redirection based on distance, and handles the RRCconnection setup request of the UE in the current cell..

If the cell is in the basic congestion state or is overloaded, the RNC generates arandom value ranging from 0 to 1 and compares the value with the parameterRedirFactorOfLDR. If the random value is equal to or smaller than the parameter, theRNC performs the next step. Otherwise, the RNC does not perform RRC redirectionbased on distance, and handles the RRC connection setup request of the UE in the

current cell. 4. The RNC sends the UE an RRC CONNECTION REJECT message containing information

on the neighboring GSM cells of the current cell.


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N-79

The procedure of RRC redirection for service steering is as follows:

1. The RNC obtains the information about the service requested by the UE and the

capability of the UE.

If the DR_ RRC_DRD_SWITCH is set to 1, the RNC determines the service

type requested by the UE. If the RNC succeeds in determining the service

type requested by the UE and the switch of RRC direction for service steering

(RedirSwitch) is set to ONLY_TO_INTER_FREQUENCY or

ONLY_TO_INTER_RAT, the RNC performs the next step. Otherwise, the

RNC handles the RRC connection setup request of the UE in the current cell.

If the DR_ RRC_DRD_SWITCH is set to 0, the RNC handles the RRC

connection setup request of the UE in the current cell.

2. Based on the cell load and the redirection factors, the RNC decides whether to

perform RRC redirection for service steering.

If the cell is in the normal state, the RNC generates a random number

between 0 and 1 and compares it with the corresponding unconditional

redirection factor (RedirFactorOfNorm). If the random number is smaller than

this factor, the RNC performs the next step. Otherwise, the RNC handles the

RRC connection setup request of the UE in the current cell.

If the cell is in the basic congestion or overload state, the RNC generates a

random number between 0 and 1 and compares it with the value of

RedirFactorOfLDR. If the random number is smaller than this factor, the

RNC performs the next step. Otherwise, the RNC handles the RRC

connection setup request of the UE in the current cell.

3. Based on the setting of RedirSwitch, the RNC takes the corresponding actions:

If RedirSwitch is set to ONLY_TO_INTER_FREQUENCY, the RNC sends an

RRC CONNECTION REJECT message to the UE, redirecting the UE to the

destination frequency carried in the message.


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N-80

DrSwitch -DR_ RRC_DRD_SWITCH

Content: When the switch is on, DRD and redirection is performed for RRC connection if retry is

required. Value range: OFF, ON


Set this parameter through SET UCORRMALGOSWITCH.

RedirSwitch

Content: This parameter specifies whether the RRC redirection algorithm is valid for the

specified traffic type. The algorithm is valid only when the RRC redirection switch is enabled

and when this parameter is set to ONLY_TO_INTER_FREQUENCY or

ONLY_TO_INTER_FREQUENCY. Value OFF indicates that RRC redirection is not allowed.

Value ONLY_TO_INTER_FREQUENCY indicates that only the RRC redirection to an inter-

frequency neighboring cell is allowed. Value ONLY_TO_INTER_RAT indicates that only the

RRC redirection to an inter-RAT neighboring cell is allowed.

Value range: OFF, ONLY_TO_INTER_FREQUENCY, ONLY_TO_INTER_RAT

Set this parameter through SET UREDIRECTION/ ADD UCELLREDIRECTION.

RedirFactorOfNorm/RedirFactorOfLDR

Content: When the load of the serving cell is within the normal range, a UE may be redirected to

another cell according to the traffic type. This parameter specifies the possibility of redirecting

the UE to another cell. When this parameter is set to 0, the RRC redirection is not performed if

the load of the serving cell is within the normal range. When the UL load state or DL load state

of the serving cell is LDR or OLC, a UE may be redirected to another cell according to the traffic

type. This parameter specifies the possibility of redirecting the UE to another cell. When this

parameter is set to 0, the RRC redirection is not performed if the load state on the serving cell is

LDR or OLC. LDR indicates basic congestion. OLC indicates overload congestion.

Value range: 0~100 Physical value range: 0~1; step: 0.01

Physical unit: %

Set these parameters through SET UREDIRECTION/ ADD UCELLREDIRECTION.


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N-81

The RNC performs the following steps:

1. The RNC selects the same-coverage inter-frequency neighboring cells of the

current cell. These neighboring cells are suitable for blind handovers

2. The RNC generates a list of candidate DRD-supportive inter-frequency cells. The

candidate cell must meet the quality requirements of DRD:

(CPICH_EcNo)RACH > DRD_EcNOnbcell

Here:

(CPICH_EcNo)RACHis the cached CPICH Ec/N0 value included in the RACH

measurement report. Note that this value is of the current cell

DRD_EcNOnbcell is the DRD threshold (DRDEcN0Threshhold) of the

neighboring cell

3. The RNC selects a target cell from the candidate cells for UE access. If thecandidate cell list is empty, the RRC DRD fails. The RNC performs RRC redirection.

If the candidate cell list contains more than one cell, the UE tries a cell randomly.

If the admission is successful, the RNC continues the RRC connection setup

procedure

If the admission to a cell fails, the UE tries admission to another cell in the

candidate cell list until an admission is successful or all admission attempts

fail

If all the admission attempts fail, then

The RNC makes an RRC redirection decision when the switch of RRCredirection after DRD failure (ConnectFailRrcRedirSwitch) is set to

ON

The RRC connection setup fails when the switch of RRC redirection

after DRD failure (ConnectFailRrcRedirSwitch) is set to OFF


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N-82

DRDEcN0Threshhold

Content: This parameter is used as the DRD Ec/No threshold of whether to

perform the blind handover. If the Ec/No measured value of the current cell is

greater than this parameter of the inter-frequency neighboring cell, this

neighboring cell can be selected to be the candidate DRD cell.

Value range: -24~0


Physical unit: dB

Set this parameter through ADD UINTERFREQNCELL/ MOD

UINTERFREQNCELL.


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N-83

When the RRC DRD fails, the RNC performs RRC redirection if the DR_RRC_DRD_SWITCH subparameter of the DrSwitch parameter is set to 1 and the

switch of RRC redirection after DRD failure (ConnectFailRrcRedirSwitch ) is set toOnly_To_Inter_Frequency orAllowed_To_Inter_RAT. The purpose of RRCredirection after DRD failure is to instruct the UE to set up RRC connection in aninter-frequency or an inter-RAT neighboring cell.

The procedure of RRC redirection after DRD failure is performed in the followingsteps:

1. The RNC selects all inter-frequency cells of the current cell.

2. The RNC selects candidate cells. The candidate cells are the cells selected in step1 but exclude the cells that have carried out inter-frequency RRC DRD attempts.

3. The RNC selects a target cell from the candidate cells for UE access.

If more than one candidate cell is available, the RNC selects a cell randomlyand redirects the UE to the cell.

If the admission is successful, the RNC continues the RRC connection setupprocedure.

If the admission attempt fails, the UE tries admission to another cell in thecandidate cell list.

If no candidate cell is available, or all the admission attempts fail:

If ConnectFailRrcRedirSwitch is set to Only_To_Inter_Frequency,the RRC connection setup fails.

If ConnectFailRrcRedirSwitch is set to Allowed_To_Inter_RAT,then:

a. If a neighboring GSM cell is configured, the RNC redirects theUE to that GSM cell.

b. If no neighboring GSM cell is configured, the RRC connectionsetup fails.


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N-84

DRDEcN0Threshhold

Content: This parameter specifies the RRC redirection strategy. OFF: RRC

redirection is not allowed. Only_To_Inter_Frequency: Only RRC redirection to

inter-frequency cells is allowed. Allowed_To_Inter_RAT: RRC redirection to

inter-frequency cells and redirection to inter-RAT cells are both allowed.

Value range: OFF, Only_To_Inter_Frequency, Allowed_To_Inter_RAT

Physical value range: OFF, Only_To_Inter_Frequency,

Allowed_To_Inter_RAT

Set this parameter through SET UDRD.


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N-85


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N-86

During the RAB processing, non-periodic DRD is used to select a suitable cell for a

UE to access according to the HSPA+ technological satisfaction, service priority, and

cell load. Non-periodic DRD is performed during RAB setup, RAB modification, orDCCC channel reconfiguration.

By using inter-frequency DRD, the RNC selects the qualified candidate cells by

considering HSPA+ technological satisfaction, cell service priority, and cell load. Then,

the RNC sequences the candidate cells according to the priority. According to the

sequence from the highest to the lowest, the UE tries accessing the cells until it is

admitted or it fails to access any cell.

If the UE fails to access any cell in the case of inter-frequency DRD, inter-RAT DRD

will be triggered.


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N-87


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N-88

MBR: Maximum Bit Rate

GBR: Guaranteed Bit Rate


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N-89

For the PS streaming service, when PS_STREAM_IU_QOS_NEG_SWITCH

subparameter of the PsSwitch parameter is set to 1, the Iu QoS negotiation function

is enabled for MBR negotiation.

For the PS BE service:

When both PS_BE_IU_QOS_NEG_SWITCH and

PS_BE_STRICT_IU_QOS_NEG_SWITCH subparameters of the PsSwitch

parameter are set to 1, the Iu QoS negotiation function is enabled, and the

RNC determines the MBR of Iu QoS negotiation based on the information

about UE capability, cell capability and rate requested by the CNother settings.

When PS_BE_IU_QOS_NEG_SWITCH is set to 1 and

PS_BE_STRICT_IU_QOS_NEG_SWITCH is set to 0, the Iu QoS negotiation

function is enabled, and the RNC determines the MBR of Iu QoS negotiation

based on the maximum rate supported by the UE rather than the cell capabilityand other settings.


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N-90

PsSwitch-PS_STREAM_IU_QOS_NEG_SWITCH

Content: When the switch is on, the Iu QoS Negotiation function is applied to the PS

STREAM service if Alternative RAB Parameter Values IE is present in the RANAPRAB ASSIGNMENT REQUEST or RELOCATION REQUEST message.



PsSw itch -PS_ BE_IU_QOS_NEG_SWITCH

Content: When the switch is on, the Iu QoS Negotiation function is applied to the PS

BE service if Alternative RAB Parameter Values IE is present in the RANAP RAB

ASSIGNMENT REQUEST or RELOCATION REQUEST message.



PsSwitch-PS_BE_STRICT_IU_QOS_NEG_SWITCH

Content: When the switch is on, the strict Iu QoS Negotiation function is applied to the

PS BE service, RNC select Iu max bit rate based on UE capacity, cell capacity, max

bitrate and alternative RAB parameter values in RANAP RAB ASSIGNMENT

REQUEST or RELOCATION REQUEST message. When the switch is off, the loose Iu

QoS Negotiation function is applied to the PS BE service, RNC select Iu max bit rate

based on UE capacity, max bitrate and alternative RAB parameter values in RANAP

RAB ASSIGNMENT REQUEST or RELOCATION REQUEST message, not consider

cell capacity, this can avoid Iu QoS Renegotiation between different cell. The switch is

valid when PS_BE_IU_QOS_NEG_SWITCH is set to ON.



Set these parameters through SET UCORRMALGOSWITCH.


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N-91


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N-92


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N-93

As described in the table, when the two switches are ON, the initial rate is

dynamically set on the basis of Ec/No in the downlink. The specific method is as

follows:

When receiving an RRC connection setup request, the RNC starts the timer

EcN0EffectTime.

Before the timer expires, the RNC dynamically sets the initial rate based on

the P-CPICH Ec/N0 carried in the RRC CONNECTION REQUEST message:

If the cell Ec/N0 reported from the UE is above the Ec/N0 threshold

(EcN0Ths), the RNC sets the actual initial rate to the smaller one of

the MBR and 384 kbit/s. Note that if the UE is in the soft handover state,

the RNC sets the actual initial rate to the smaller one of the MBR and

384 kbit/s when any of the cells in the active set meets the threshold.

If the cell Ec/N0 is below or equal to the Ec/N0 threshold (EcN0Ths) or

the RRC CONNECTION REQUEST message does not carry the

information about Ec/N0, the RNC sets the actual initial rate to the

smaller one of the MBR and the initial rate of the downlink BE service

(DlBeTraffInitBitrate).


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N-94

PsSwit ch -PS_STREAM_IU_QOS_NEG_SWITCH

Content: When the switch is on, the dynamic channel reconfiguration control

algorithm is used for the RNC.



PsSwitch-PS_BE_INIT_RATE_DYNAMIC_CFG_SWITCH

Content: When the switch is on, the initial rate of the service should be

dynamically configured according to the value of Ec/No reported by the UE

when the PS BE service is established.



Set these parameters through SET UCORRMALGOSWITCH.


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N-95

EcN0EffectTime

Content: This parameter specifies the time duration when the reported Ec/No

is valid. The reported Ec/No is valid for the period (starting from the time whenthe RRC connection request is initiated) specified by this parameter.



Physical unit: ms

Set this parameter through ADD UCELLFRC/ SET UFRC.

EcN0Ths

Content: This parameter specifies the threshold for determining the signalquality in a cell. If the reported Ec/No exceeds the value of this parameter, youcan infer that the signal quality in the cell is good and a high code rate can be

set for initial access. Value range: 0~49

Physical value range: -24.5~0 (0: -24.5, 1: -24 49: 0) Physical unit: dB

Set this parameter through ADD UCELLFRC/ SET UFRC.

DlBeTraffIni tBitrate

Content: DL BE traffic Initial bit rate. When DCCC function is enabled, thedownlink initial bit rate will be set to this value if the downlink max bit rate ishigher than the initial bit rate.

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

Physical value range: 8, 16, 32, 64, 128, 144, 256, 384 Physical unit: kbit/s

Set this parameter through SET UFRC.


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N-96


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N-97

DraSwitch -DRA_HSUPA_DCCC_SWITCH

Content: When the switch is on, the DCCC algorithm is used for HSUPA. The

DCCC switch must be also on before this switch takes effect.



Set this parameter through SET UCORRMALGOSWITCH.

HsupaInit ialRate

Content: HSUPA BE traffic Initial bit rate. When DCCC algorithm switch and

HSUPA DCCC algorithm switch are enabled, the uplink initial bit rate will be

set to this value if the uplink max bit rate is higher than the initial bit rate.

Value range: D8, D16, D32, D64, D128, D144, D256, D384, D608, D1440,

D2048, D2880, D5740

Physical value range: 8, 16, 32, 64, 128, 144, 256, 384, 608, 1440, 2048, 2880,

5740

Physical unit: kbit/s

Set this parameter through SET UFRC.


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N-98

If the cell has sufficient code and CE resources, the RNC sets the candidate target

rate to the one that matches the cell resource surplus. Then, the RNC sets the target

rate to the greater one of the candidate target rate and the GBR.

In the case of soft handover, the actual target rate is the candidate target rate set by

the RNC.

In the case of DCCC rate upsizing, if the rate upsizing fails, the target rate is the

greater one of the candidate target rate and the pre-upsizing DCCC rate.


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N-100


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N-101


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N-102

Preemption and queuing guarantee the success in the access of a higher-priority user

by forcibly releasing the resources of a lower-priority user.

Preemption and queuing are applicable to the following scenarios:

Setup or modification of a service

Hard handover or SRNS relocation

UE state transition from CELL_FACH to CELL_DCH


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N-103

The following table describes the selection of the target cell for preemption or queuing:

DRDSwitch for

Service

Steering

Power-BasedDRD Switch

for Load

Balancing

Code-BasedDRD Switch

for Load

Balancing

Target Cell for Preemption or Queuing

ON

ON - The cell with the lightest load among the cells

with the highest service priority.- ON

4 wcdma ran12 load control algorithm and parameters issue1.00

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