OMF000406 Advanced Radio Resource Management-training-20060531-A-1.0.ppt

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OMF000406 Advanced Radio Resource management

ISSUE 1.0

HUAWEI TECHNOLOGIES CO., LTD. Page 2All rights reserved

To satisfy different environments, many

kinds of advance radio resource

management algorithm are adopted,

including Huawei II CH allocation

algorithm, H/F rate CH conversion,

TCH/SDCCH conversion, PCDH/TCH

conversion. They are designed to

improve the performance of network


Upon completion this course, you will be able to:

Master the main idea and parameters of HWII CH Ass.

Algorithm

Master the parameters of H/F rate CH conversion

Understand TCH/SDCCH conversion and TCH/PDCH

Conversion


Chapter 1 HWChapter 1 HW II II CH Ass. CH Ass. AlgorithmAlgorithm

Chapter 2 H/F CH Conversion Chapter 2 H/F CH Conversion

Chapter 3 TCH/SDCCH conversionChapter 3 TCH/SDCCH conversion

Chapter 4 TCH/PDCH ConversionChapter 4 TCH/PDCH Conversion


Channel Assignment Algorithm

HW I Channel Allocation algorithm

uses the sequent selection mode to allocate channels

The advantage is terse and high efficiency

It is not able to allocate CH according to TRX priority,

interference, etc.

HW II Channel Allocation algorithm

allocates channels by optimum

Always choose the best one but lower efficiency


HW II channel allocation Algorithm

HW II channel allocation is based on interference, TRX priority

and performance record in history

Interference: extracted from MR

TRX priority: configured in OMC

Performance record in history: realized by BSC

automatically


HW II channel allocation Algorithm

In the following condition, increase CH priority

Assignment successful

In the following condition, decrease CH priority

Assignment fails

Call drop occur

Interference exist

Update priority periodically

Set up CH priority in one BM periodically to avoid the effect

of short time interference


Parameter introduction

SD allocation priority allowed

Range: Yes, No

Default: Yes

Description: If the setting is "No", then the roll selection is a

dopted for SDCCH allocation. If the setting is "Yes", then th

e optimum selection is adopted.

iInterf. priority allowed

Range: Yes, No

Default: Yes

Description: Indicates whether the interference record priorit

y is allowed.


Parameter introduction Active Ch Inter. Meas. Allowed

Range: Yes, No

Default: Yes

Description: Indicates whether the interference of the active

channel is measured. If the setting is "No", the system

does not judge whether the active channel is interfered, nor

sending interference indication message. Otherwise,

judgment will be made.

Allocation TRX priority allowed

Range: Yes, No

Default: Yes

Description: Whether the TRX priority is used for allocation.



History records priority allowed

Range: Yes, No

Default: Yes

Description: Whether the history record priority is used for

allocation.

Balance traffic allowed

Range: Yes, No

Default: Yes

Description: If the setting is "No", the channel next to the

previously allocated channel will be the starting channel for

searching a qualified channel to be allocated.



Interf. of UL Level thrsh.

Range:0~63,(-110dBm~-47dBm)grade

Default:31

Description: Threshold of uplink strength interference. If the uplink strength of a channel is greater than this threshold and the uplink signal quality is worse than or equal to the “Interf. of UL Qual. Thrsh.”, then uplink interference exists.

Interf. of UL qual. Thrsh.

Range:0~70, (RQ0~RQ7)

Default:40

Description: Threshold of uplink quality interference. See the description of “Interf. of UL level Thrsh. “.

Interf. of DL Level thrsh. and Interf. of DL qual. Thrsh.

Are the same as uplink



Filter length for TCH Level

Range:1~32

Default:6

Description: Used to filter the receiving signal strength of speech/data channel.

Filter length for TCH Qual.

Range:1~32

Default:6

Description: Used to filter the receiving signal quality of speech/data channel.

Filter length for SDCCH Level and Filter length for SDCCH Qual.

Are the same as previous parameter


Parameter introduction Update Period of CH Record

Range:1~1,440

Unit: minute

Default: 30

Description: In HW_II channel management algorithm, every time the duration (set by this parameter) expires, the history record of every channel will be refreshed through subtracting the value of “Update Freq. of CH record ". Thus the channel priority is raised. This parameter together with the "Update Freq. of CH record " works to prevent a channel from being allocated again, which has been deteriorated for a period.

Update Freq. Of CH record

Range:0~63

Default:2

Description: The history record priority higher than the value of this parameter will be refreshed through subtracting the value of this parameter. See the description of “Update Period of CH record”



TRX priority

Description: The priority of TRX (valid in HW_II channel

allocation algorithm only.).

Range: Level 0~Level 7

Default: Level 0







Parameter introduction Support dynamic conversion between TCH/F and TCH/H. Channels initially configured as TCH

/H can not be converted.

TCH Rate adjust allowed

Range: Yes, No

Default: No.

Description: It is used to decide whether full rate TCH can be converted into half-rate TCH.

“Yes” means the conversion is feasible, while “No” means not. For the latter case, the half-

rate TCH converted will change back to the full rate TCH

Idle Thrsh. For TCH/F priority

Range: 0~255

Unit: Channel number

Default:2

Description: Parameter is used to judge which type of channel is to be allocated. If channe

l number of idle full rate TCH is greater than this threshold, then idle full rate TCH is allocat

ed first for better voice quality. otherwise, half rate TCH is allocated first.



TCH Rate adjust Traffic Thrsh (%)

Range:0~100

Unit:%

Default:80

Description: It is one of the terms for the full rate TCH to co

nvert into the half-rate TCH. Only if the traffic (number of cu

rrently occupied channels / number of available channels in

a cell) is greater than the threshold, and “TCH Rate Conver

sion" is set as “Yes", can the full rate TCH convert into the h

alf rate TCH to expand system capacity.



MIN Recovery Time of TCH/H

Range:0~65535

Unit: second

Default:600

Description: The minimum interval that half-rate TCH recovers into full rate TCH.

TCH/F Forbid TCH Rate Adjust

Range:0–255

Default:1

Description: The value of the parameter is one condition for the adjustment from

full rate TCH to half rate TCH. When the number of available half rate TCH in the

cell is more than the value, system adjust full rate TCH as half rate TCH to

enlarge the capacity.



Chapter 2 H/F CH ConversionChapter 2 H/F CH Conversion





Support dynamic conversion between TCH/F and SDCCH.

Not support dynamic conversion between TCH/H and SDCCH.

SD Dynamic Allocation Allowed

Range: Yes, No

Default: Yes

Description: Indicates whether SDCCH dynamic allocation is allowed.



Idle SD Thrsh.N1

Range:0~63

Default:2

Description: When the number of idle SDCCH channels is less than or equal to the “Idle SD Thrsh.”, the system will try to find available TCHs and convert them to SDCCH channels.

Note:The conditions to Initiate the TCH-to-SDCCH conversion flow:

− The number of idle SDCCH channels+8 is less than or equal to “Idle SD Thrsh.”.

− The number of current idle full rate TCH channels is more than 4 or more than the number of TRXs.

− The number of current SDCCH channels is less than “Cell SD maximum.



Cell SD Maximum Range:0~255

Default: Configured SDCCHs + 8

Description: The maximum number of SDCCHs in the cell.

Note

The processing flow of recovering SDCCH to TCH is as follows: a timer Count is set for each cell. Every time a TCH is converted into an SDCCH, the Count is set to ResTime. Count is adjusted every 3 seconds. If the current idle SDCCH channels > 8 +Idle TCH Thrsh., then: the Count minus 3. If the current idle SDCCH channels < 8 + Idle TCH Thrsh., then plus 12 to Count, but the Count must not exceed ResTime. If the current idle SDCCH channels = 8 + Idle TCH Thrsh., then Count remains unchanged. After the adjustment, if Count 0, then one TCH channel will be recovered.



Due to TRX hardware processing capability restriction, at most 2 time

slots can be configured as SDCCH channels for each TRX. To initiate

the TCH-to-SDCCH conversion, if the selected TCH is occupied, the

connection will be handed over to other idle TCH channel in this cell.

During dynamic SDCCH channel allocation, each time only one TCH is

converted into SDCCH. So does the SDCCH-to-TCH conversion.

During the TCH-to-SDCCH conversion, TCH channels on TRX in where

BCCH is located should not be selected



TCH Minimum Recovery Time(s)

Range:60~3600

Unit: second

Default:600

Description: The minimum interval for the TCH recovery after TCH-to-SD

CCH conversion.








Support dynamic conversion between TCH/F and PDCH. Channels initially configured as PDCH can not be converted.

Idle TCH Thrsh. N1

Range:0~255

Default: 0

Description: Only when the number of idle TCH channels is less than or equal to the “Idle TCH Thrsh. N1” and the duration is longer than “Apply_TCH Decision Period T(m)”, can PDCH-to-TCH conversion be performed.

Apply- TCH Decision Period T(m)

Range:0~65535

Unit: minute

Default:0

Description: The duration to judge whether PDCH to TCH conversion can be performed.


In this course, we have learned the parame

ter of HW II CH Ass. Algorithm, H/F rate CH

conversion, TCH/SDCCH conversion and

TCH/PDCH Conversion

Apllication should be depended on the real

environment

SummarySummary

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Thank You

Documents

OMF000406 Advanced Radio Resource Management-training-20060531-A-1.0.ppt