1 © Nokia Siemens Networks RN31638EN20GLA0 Course Content Radio Resource Management Overview Parameter Configuration Common Channels & Power Control Load Control Admission Control Packet Scheduling Handover Control Resource Manager HSDPA RRM & parameters HSUPA RRM & parameters HSPA+ RRM (Rel. 7/8)
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RANPARModule Objectives
At the end of the module you will be able to:
Explain the functions of Resource Manager
Explain code tree usage optimisation & parameters
* © Nokia Siemens Networks RN31638EN20GLA0
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
UL Channelisation 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 Channelisation Codes per user & TTI from the HSDPA pool
CodeTree
Optimisation
UL: Scrambling Codes separate the UE's
All physical channels are spread with individual Channelisation Codes, Cm(n) and subsequently by the scrambling code, CFSCR
User
data
Widespread
data
Channelisation
Code
Scrambling
Code
Channelisation 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 512) are available (Nokia RAN does not support SF = 512)
In UL code order 2 to 7 (SF 4 to 256) are available
Code Allocation Algorithm chooses the correct Channelisation Code depending on the TFC type
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)=(…)
* © Nokia Siemens Networks RN31638EN20GLA0
Spreading Code Allocation – Example
Ordinary DL speech channel, requires 30 ksps physical capacity (AMR 12.2 – 4.75 kbit/s).
The code order is 8, 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 6.
AMR Speech
Code Order
DL Code Allocation
max. 166 codes @ SF=256 available for the associated DCHs & non-HSDPA users
when code multiplexing is used, up to 3 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
* © Nokia Siemens Networks RN31638EN20GLA0
Pilot (P-CPICH) and BCCH (P-CCPCH) have fixed code allocation
P-CPICH: CH256,0
P-CCPCH: CH256,1
AICH: CH256,2
PICH: CH256,3
S-CCPCH code allocation depends on number of active S-CCPCH in Nokia RAN
With 1 S-CCPCH: CH64,1
Spreading Code Allocation
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
Re-arrangements in the code tree is 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: CodeTreeOptimisation
The parameter indicates if rearrangement can be applied to a specific cell.
range: 0 (optimization not used), 1 (optimization used) default: 1;
WCEL: CodeTreeOptTimer
The parameter defines the timer value that triggers code tree optimization, if it is not triggered otherwise
range: 1 ... 65535 s, step 1 s default: 3600 s;
WCEL: CodeTreeUsage
The parameter defines the minimum usage of code tree before rearrangement is applied to a specific cell.
range: 0 ... 100 %, step 1 % default: 40%;
WCEL: MaxCodeReleases
The parameter defines the maximum number of code release actions allowed in a code tree before rearrangement is applied to this code tree.
range: 1 ... 65535, step 1 default: 40;
* © Nokia Siemens Networks RN31638EN20GLA0
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 but 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
ULScrCodeMin
Benedikt Aschermann
Benedikt Aschermann
Code for one
Code for one
At the end of the module you will be able to:
Explain the functions of Resource Manager
Explain code tree usage optimisation & parameters
* © Nokia Siemens Networks RN31638EN20GLA0
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
UL Channelisation 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 Channelisation Codes per user & TTI from the HSDPA pool
CodeTree
Optimisation
UL: Scrambling Codes separate the UE's
All physical channels are spread with individual Channelisation Codes, Cm(n) and subsequently by the scrambling code, CFSCR
User
data
Widespread
data
Channelisation
Code
Scrambling
Code
Channelisation 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 512) are available (Nokia RAN does not support SF = 512)
In UL code order 2 to 7 (SF 4 to 256) are available
Code Allocation Algorithm chooses the correct Channelisation Code depending on the TFC type
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)=(…)
* © Nokia Siemens Networks RN31638EN20GLA0
Spreading Code Allocation – Example
Ordinary DL speech channel, requires 30 ksps physical capacity (AMR 12.2 – 4.75 kbit/s).
The code order is 8, 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 6.
AMR Speech
Code Order
DL Code Allocation
max. 166 codes @ SF=256 available for the associated DCHs & non-HSDPA users
when code multiplexing is used, up to 3 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
* © Nokia Siemens Networks RN31638EN20GLA0
Pilot (P-CPICH) and BCCH (P-CCPCH) have fixed code allocation
P-CPICH: CH256,0
P-CCPCH: CH256,1
AICH: CH256,2
PICH: CH256,3
S-CCPCH code allocation depends on number of active S-CCPCH in Nokia RAN
With 1 S-CCPCH: CH64,1
Spreading Code Allocation
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
Re-arrangements in the code tree is 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: CodeTreeOptimisation
The parameter indicates if rearrangement can be applied to a specific cell.
range: 0 (optimization not used), 1 (optimization used) default: 1;
WCEL: CodeTreeOptTimer
The parameter defines the timer value that triggers code tree optimization, if it is not triggered otherwise
range: 1 ... 65535 s, step 1 s default: 3600 s;
WCEL: CodeTreeUsage
The parameter defines the minimum usage of code tree before rearrangement is applied to a specific cell.
range: 0 ... 100 %, step 1 % default: 40%;
WCEL: MaxCodeReleases
The parameter defines the maximum number of code release actions allowed in a code tree before rearrangement is applied to this code tree.
range: 1 ... 65535, step 1 default: 40;
* © Nokia Siemens Networks RN31638EN20GLA0
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 but 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
ULScrCodeMin
Benedikt Aschermann
Benedikt Aschermann
Code for one
Code for one
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