1 Nokia Siemens Networks RN31638EN40GLA0

Resource Manager

2 Nokia Siemens Networks RN31638EN40GLA0

Resource Manager:

Module Objectives

At the end of the module you will be able to:

Explain the functions of Resource Manager

Explain code tree usage optimization & parameters

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Resource Manager RM

Main function: allocate logical radio resources of BS according to the channel request by the RRC layer for each radio connection.

The RM is located in the RNC and it works in close co-operation with AC & PS.

The actual input for resource allocation comes from AC/PS and RM informs the PS about the resource situation

The RM is able to switch codes & code types for different reasons such as SHO & defragmentation of code tree

Manages the BS logical resources BS reports the available logical HW resources

Requests for other resources such as ATM Transport resource manager

RNC HW manager (L1/L2)

Maintains the code tree allocates the DL Channelization Codes, UL Scrambling Code, UL Channelization Code type

prevents Code Tree fragmentation, which may cause extra IF or IS HO's

with HSDPA, RM allocates a number of codes to a HSDPA code pool

for HSDPA users NodeB PS then allocates Channelization Codes per user & TTI from the HSDPA pool

CodeTreeOptimization WCEL; 0 (not used);

1 (used)

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Resource Manager

DL: Scrambling codes separate the cells (sectors); Channelization codes separate connections

UL: Scrambling Codes separate the UE's

All physical channels are spread with individual Channelization Codes, Cm(n) and subsequently by the scrambling code, CFSCR

User

data

Widespread

data

Channelization

Code

(Spreading

Code)

Scrambling

Code

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Channelization Code Allocation

The codes are layered from 0 to 11 according to the Spreading Factor (SF)

Cm(n) : The code order, m, and the code number, n, designates each and every code in the layered orthogonal code sequences

In DL code order 2 to 8 (SF 4 to 256) are available

In UL code order 2 to 8 (SF 4 to 256) are available for R99, HSUPA also uses SF2

C 0 (0)=(1)

C 1 (0)=(1,1)

C 1 (1)=(1,-1)

C 2 (0)=(1,1,1,1)

C 2 (1)=(1,1,-1,-1)

C 2 (2)=(1,-1,1,-1)

C 2 (3)=(1,-1,-1,1)

C 3 (0)=()

C 3 (1)=()

C 3 (2)=()

C 3 (3)=()

C 3 (4)=()

C 3 (5)=()

C 3 (6)=()

C 3 (7)=()

Code Order 0 (SF 1)

Code Order 1 (SF 2)

Code Order 2 (SF 4)

Code Order 3 (SF 8)

Code Allocation Algorithm chooses the correct Channelization Code depending on the TFC type

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Spreading Code Allocation Example

Ordinary DL speech channel, requires 30 ksps physical capacity (AMR 12.2 4.75 kbit/s).

The code order is 7, which means there are 128 chips to illustrate 1 symbol (2n, n=7).

If the requested channel is 120 kbit/s (including DPCCH & channel coding) data

channel, then the code order is 5.

Code Order

Channel symbolrate

(ksps)

Channel bitrate (kbps)

SF DPDCH

bits/frame

9 15 7.5 512 40

8 30 15 256 160

7 60 30 128 340

6 120 60 64 600

5 240 120 32 1400

4 480 240 16 2880

3 960 480 8 6080

2 1920 960 4 12480

AMR Speech

64 kbps data

128 kbps data

384 kbps data

low rate AMR Speech possible

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SF = 128

SF = 256

SF = 64

SF = 32

SF = 8

SF = 16

SF = 4

SF = 2

SF = 1

Codes for the cell common channels

Code for one

HS-SCCH

Codes for 5

HS-PDSCH's

DL Code Allocation Common Channels

Pilot (P-CPICH) and BCCH (P-CCPCH) have fixed code allocation

P-CPICH: CH256,0 P-CCPCH: CH256,1

AICH and PICH codes in NSN RAN

AICH: CH256,2 PICH: CH256,3

S-CCPCH code allocation depends on number of active S-CCPCH in NSN RAN

With 1 S-CCPCH: CH64,1

P-C

PIC

H

P-C

CP

CH

AIC

H

PIC

H

S-CCPCH1

(FACH)

X X

X

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SF = 128

SF = 256

SF = 64

SF = 32

SF = 8

SF = 16

SF = 4

SF = 2

SF = 1

Codes for the cell common channels

Code for one

HS-SCCH

Codes for 5

HS-PDSCH's

max. 166 codes @ SF=256 available for the associated DCHs & non-HSDPA users, if five HS-PDSCHs and one HS-SCCH are allocated

when code multiplexing is used, up to 4 HS-SCCH are transmitted and need a code

When HSDPA is enabled at least 5 codes are allocated

Code allocation is dynamic from RAS06 on when more than 5 codes are allocated

DL Code Allocation

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Code Tree Optimization / De-fragmentation

A code is always allocated from the optimum location in the code tree. It makes the allocated code and the codes in the branches below and above

the allocated code unavailable

Code tree will fragment quickly if releases is not re-arranged

Code tree Re-arrangements done by reallocating the codes in better locations

In the above example 4 codes of equal order are allocated. The best locations are in the same branch and very close to one another. The badly located code is released and

optimally reallocated allowing the use of upper layer codes

Codes are only reallocated when there is a benefit at two code tree layers above the code being reallocated

CodeTree

Optimisation WCEL; 0 (not used);

1 (used)

CodeTree

OptTimer WCEL; 1..65535; 1;

3600s

CodeTreeUsage min. usage of code

tree before

rearrangement

WCEL;

0..100%; 1%;

40%

MaxCode

Releases Max. code releases

before rearrangement

WCEL; 1..65535; 1; 40

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DL & UL Scrambling Code Allocation

Each cell uses 1 semi-permanent DL Primary Scrambling Code that is allocated by O&M. It is taken into use when the cell is started, requiring scrambling code planning , e.g. for adjacent cells.

PriScrCode identifies the DL scrambling code of the cell is applied to all physical channels except SCH

UL Scrambling Codes: are mobile specific and are allocated in connection establishment.

The codes are indexed from 0 to 224(16,777,216). Different UEs within the same cell must use different UL scrambling codes

RM allocates UL scrambling code from a list of codes inside a single RNC. For example RNC_123 can allocate codes from 1000000 to 1999999; finally starts from 1000000 again. This allocation unit saves all used codes in a table and checks if allocated code is used or not

Since different RNCs allocate their own codes there is a possibility that two mobiles get the same code. With code planning and Iur signaling (negotiating within RNCs) the above problem is avoided.

ULScrCodeMin the minimum value of UL scrambling code; it is unique for each MS.

The maximum UL scrambling code number is calculated by the system as

ULScrCodeMin + n*m

where n is the number of ICSUs in the RNC & m=8192 is the max number of user/ ICSU

This suggests careful configuration when considering HW upgrades to avoid overlaps

ICSU: Interference Control & Signalling Unit

PriScrCode WCEL; 0..511; 1; no default

ULScrCodeMin RNAC; 8192..16.777.215;

1; 1000000