www.huawei.com
Objectives
z
Upon completion of this course, you will be able to:
Know the load control principles
Know the load control realization methods in WCDMA system
Contents
1. Load Control Overview
Contents
1. Load Control Overview
Load Definition
z
Load: the occupancy of capacity
z
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)
Uplink Load Definition
z
Cell Load Factor:
rise
noise
UL
1
1
−
=
η
NP
RTWP
rise
noise
=
Downlink Load Definition
Common Measurement in Node B
Scenario
UL Load
Cell Load Factor (based on RTWP)
RTWP (Received Total Wideband Power)
R99 load control
Transmitted carrier power of all codes not
used for HS-PDSCH or HS-SCCH
transmission
R99 load control
Total Carrier Power (TCP)
R99 and HSDPA load
control
DL Load
HS-DSCH Required Power
HSDPA load control
The Objectives of Load Control
z
Keeping system stable
z
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 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
Load Measurement
z
The objectives of LDM (LoaD Measurement)
Measure the system load
Filter the measured data according to the requirement of different
load control algorithms
z
Major Measurement Quantities
Uplink Received Total Wideband Power (RTWP)
Downlink Transmitted Carrier Power (TCP)
TCP of all codes not used for HSDPA transmission
LDM procedure
z
Smooth Window Filtering on the RNC Side
N : the size of the smooth window
: the reported measurement value
1 0
( )
N n i iP
P n
N
− − ==
∑
P
n
Parameters for LDM (1)
z
CHOICERPRTUNITFORULBASICMEAS
/CHOICERPRTUNITFORDLBASICMEAS (Time unit for UL/DL basic
meas rprt cycle)
Value Range: TEN_MSEC, MIN
Parameters for LDM (2)
z
TENMSECFORULBASICMEAS/TENMSECFORDLBASICMEAS (UL/DL
basic meas rprt cycle, Unit:10ms)
Value Range: 1~6000
Recommended value: 20, namely 200ms
z
MINFORULBASICMEAS/MINFORDLBASICMEAS (UL/DL basic meas
rprt cycle, Unit: min)
Value Range: 1~60
Parameters for LDM (3)
z
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
Parameters for LDM (4)
z
The parameters for smoothing filter window
Parameter Name
Parameter ID
Value Range
Recommend
Value
PUC moving average filter length
PucAvgFilterLen
1–32
32
UL LDR moving average filter length
UlLdrAvgFilterLen
1–32
25
DL LDR moving average filter length
DlLdrAvgFilterLen
1–32
25
UL CAC moving average filter length
UlCACAvgFilterLen
1–32
3
DL CAC moving average filter length
DlCACAvgFilterLen
1–32
3
UL OLC moving average filter length
UlOLCAvgFilterLen
1–32
25
DL OLC moving average filter length
DlOLCAvgFilterLen
1–32
25
Parameters for HSDPA LDM (1)
z
CHOICERPRTUNITFORHSDPAPWRMEAS (Time unit of
HSDPA
need pwr
meas cycle)
Value Range: TEN_MSEC, MIN
Recommended value: TEN_MSEC, means the time unit is 10ms
z
CHOICERPRTUNITFORHSDPARATEMEAS (Time unit of
HSDPA bit
rate
meas cycle)
Value Range: TEN_MSEC, MIN
Parameters for HSDPA LDM (2)
z
TENMSECFORHSDPAPWRMEAS (
HSDPA need pwr
meas
cycle,Unit:10ms)
Value Range: 1~6000
Recommended value: 10, namely 100ms
z
TENMSECFORHSDPAPRVIDRATEMEAS (
HSDPA bit rate
meas
cycle,Unit:10ms)
Value Range: 1~6000
Parameters for HSDPA LDM (3)
z
MINFORHSDPAPWRMEAS (
HSDPA need pwr
meas cycle, Unit:
min)
Value Range: 1~60
Recommended value: none
z
MINFORHSDPAPRVIDRATEMEAS (
HSDPA bit rate
meas cycle,
Unit: min)
Value Range: 1~60
Parameters for HSDPA LDM (4)
z
HSDPANEEDPWRFILTERLEN (
HSDPA need power
filter len)
Value Range: 1~32
Recommended value: 1
z
HSDPAPRVIDBITRATEFILTERLEN (
HSDPA bit rate
filter len)
zValue Range: 1~32
Priority
z
The service of user with low priority will be affected by the load
control algorithms first
z
Three kinds of priority
User Priority
User Integrate Priority
User Priority
z
There are three levels of user priority (1, 2, and 3)
gold (high), silver (middle) and copper (low) user
User priority
Gold
Silver
Copper
Uplink
128kbps 64kbps 32kbps
Downlink
128kbps 64kbps 32kbps
gold
user
Pay $100
for 3G
services
User Priority
z
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
ARP
1
2
3
4
5
6
7
8
9
10 11 12 13 14
RAB Integrate Priority
z
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
Example for RAB Integrate Priority
Service
ID
ARP
Traffic Class
Bear
type
A
1 Interactive
DCH
B
1 Interactive
HSDPA
C
2 Conversational
DCH
D
2 Background
DCH
Services attribution in the cell
Based on ARP, HSDPA priority is higher
Based on Traffic Class, HSDPA priority is higher
Service
ID
ARP
Traffic Class
Bear
type
B
1
Interactive
HSDPA
A
1
Interactive
DCH
C
2
Conversational
DCH
D
2
Background
DCH
Service
ID
Traffic Class
ARP
Bear
type
C
Conversational
Interactive
Interactive
2
DCH
B
1
HSDPA
A
1
DCH
User Integrate Priority
z
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.
Contents
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)
Contents
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)
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
PUC Realization
z
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.
Parameters for PUC Algorithm Switch
z
NBMSWITCH (Cell algorithm switch)
Value Range:
PUC
Default status: OFF
z
PUCPERIODTIMERLEN (PUC period timer length)
Value Range:6s~86400s
Parameters for PUC (1)
z
SPUCHEAVY (Load level division threshold 1)
Value Range: 0 to 100%
Recommended value: 70, namely 70%
z
SPUCLIGHT (Load level division threshold 2)
Value Range: 0 to 100%
Recommended value: 45, namely 45%
z
SPUCHYST (Load level division hysteresis)
Value Range: 0 to 100%
Parameters for PUC (2)
z
OFFSINTERLIGHT (Sintersearch offset 1)
Value Range: -10 to 10
Physical Value Range: -20 to 20dB, step 2dB
Recommended value: -2, namely -4dB
z
OFFSINTERHEAVY (Sintersearch offset 2)
Value Range: -10 to 10
Physical Value Range: -20 to 20dB, step 2dB
Parameters for PUC (3)
z
OFFQOFFSET1LIGHT (Qoffset1 offset 1)
Value Range: -20 to 20
Physical Value Range: -20 to 20dB, step 1dB
Recommended value: -4, namely -4dB
z
OFFQOFFSET2LIGHT (Qoffset2 offset 1)
Value Range: -20 to 20
Physical Value Range: -20 to 20dB, step 1dB
Parameters for PUC (4)
z
OFFQOFFSET1HEAVY (Qoffset1 offset 2)
Value Range: -20 to 20
Physical Value Range: -20 to 20dB, step 1dB
Recommended value: 4, namely 4dB
z
OFFQOFFSET2HEAVY (Qoffset2 offset 2)
Value Range: -20 to 20
Physical Value Range: -20 to 20dB, step 1dB
Contents
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)
Why we need CAC?
z
WCDMA is an interference limited system, after a new call is
admitted, the system load will be increased
z
If a cell is high loaded, a new call will cause ongoing user
dropped
z
We must keep the coverage planed by the Radio Network
CAC Code Resource Admission
z
For handover services
The current remaining code resource should be enough for the
service
z
For other R99 services
RNC shall ensure the remaining code does not exceed the
configurable thresholds after admission of the new service
z
For HSDPA services
Parameters for Code Resource
Admission
z
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
CAC Power Resource Admission
z
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
z
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
z
Algorithm 3: loose call admission control algorithm
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 the
N
threshold?
RTWP
P
N
UL
= 1
−
η
η
Δ
η
η
η
UL _
predicted
=
UL
+
Δ
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
Y
Smaller than the
N
threshold?
)
(N
P
P
Δ
P
N
P
(
)
+
Δ
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 the
N
threshold?
∑
==
N i i totalN
ENU
ENU
1)
(
newENU
new totaltotal
N
ENU
N
ENU
ENU
(
+
1
)
=
(
)
+
max/
)
1
(
N
ENU
ENU
ENULoad
=
total+
Typical equivalent number of users
Equivalent Number of User (ENU)
Service
For Already Existing Users
For New Incoming Call
3.4 kbit/s SIG
0.2669
0.4569
13.6 kbit/s SIG
0.4531
1.2131
3.4 + 12.2 kbit/s
0.7662
1.3210
3.4 + 8 kbit/s (PS)
0.5106
0.6325
3.4 + 16 kbit/s (PS)
0.9215
1.0472
3.4 + 32 kbit/s (PS)
2.1319
2.2680
3.4 + 64 kbit/s (PS)
3.2479
3.4188
3.4 + 128 kbit/s (PS)
6.2219
6.4143
3.4 + 144 kbit/s (PS)
6.9731
7.1888
3.4 + 256 kbit/s (PS)
11.2941
11.5245
3.4 + 384 kbit/s (PS)
17.0178
17.1897
Parameters for Power Resource
Admission Algorithm Switch
z
NBMULCACALGOSELSWITCH (Uplink CAC algorithm switch)
Value Range:
ALGORITHM_OFF, ALGORITHM_FIRST, ALGORITHM_SECOND, and
ALGORITHM_THIRD
z
NBMDLCACALGOSELSWITCH (Downlink CAC algorithm switch)
Value Range:
ALGORITHM_OFF, ALGORITHM_FIRST, ALGORITHM_SECOND, and
Parameters for
Load Prediction
(1)
z
CELLENVTYPE (Cell environment type)
Value Range:
TU: typical urban district
RA: rural area
HT: hill terrain
Default value: TU
z
BACKGROUNDNOISE (Background noise)
Value Range: 0 to 621
Parameters for
Load Prediction
(2)
z
ULINTERFACTOR (UL neighbor interference factor )
Value Range: 0 to 200
Physical Range: 0 to 2, step: 0.01
Recommended value: 60, namely 0.6
z
NONORTHOFACTOR (DL Nonorthogonality factor)
Value Range: 0 to 1000
Physical Range: 0 to 1, step: 0.001
Parameters for Power Resource
Admission (1)
z
ULCCHLOADFACTOR (UL common channel load factor)
Value range: 0 to 100%
Recommended value: 0, namely 0%
z
DLCCHLOADRSRVCOEFF (DL common channel load reserved
coefficient)
Value range: 0 to 100%
Parameters for Power Resource
Admission (2)
z
ULCONVAMRTHD (UL threshold of Conv AMR service)
Value range: 0 to 100%
Recommended value: 75, namely 75%
z
ULCONVNONAMRTHD (UL threshold of Conv non_AMR service)
Value range: 0 to 100%
Parameters for Power Resource
Admission (3)
z
ULOTHERTHD (UL threshold of other services)
Value range: 0 to 100%
Recommended value: 60, namely 60%
z
ULHOTHD (UL handover access threshold)
Value range: 0 to 100%
Parameters for Power Resource
Admission (4)
z
DLCONVAMRTHD (DL threshold of Conv AMR service)
Value range: 0 to 100%
Recommended value: 80, namely 80%
z
DLCONVNONAMRTHD (DL threshold of Conv non_AMR service)
Value range: 0 to 100%
Parameters for Power Resource
Admission (5)
z
DLOTHERTHD (DL threshold of other services)
Value range: 0 to 100%
Recommended value: 75, namely 75%
z
DLHOTHD (DL handover access threshold)
Value range: 0 to 10%
Parameters for Power Resource
Admission (6)
z
ULTOTALEQUSERNUM (UL total equivalent user number)
Value range: 1 to 200
Recommended value: 80, namely UL ENUmax = 80
z
DLTOTALEQUSERNUM (DL total nonhsdpa equivalent user
number)
Value range: 1 to 200
CAC Credit Resource Admission
z
Credit resource admission is similar with code resource
admission
z
For handover services
The current remaining credit resource should be enough for the
service
z
For other R99 services
RNC shall ensure the remaining code does not exceed the
Parameters for Credit Resource
Admission (1)
z
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
Parameters for Credit Resource
Admission (2)
z
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:
Contents
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)
Why we need IAC?
z
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
z
“Intelligent” means the algorithm can increase admission
IAC – Rate negotiation
z
Iu QoS Negotiation: based on
the UE capability
Physical layer capability
Transport channel capability
RLC capability
z
RAB Downsizing: based on
system load
Channelization codes
Iub transmission resources
Radio resources
•
384kbps
•
256kbps
•
128kbps
•
64kbps
•
32kbps
Maximum allowed bit rate
IAC – Direct Retry based on service
z
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
IAC – Preemption
High priority
Preempting resource
z
The user with high priority can preempt the resource of users
with low priority
z
Triggering resource for Preemption
Power (or ENU), SF (spreading factor), Iub transmission resource,
IAC – Queuing
z
After CAC rejection, UE can wait a moment and queue, then try
to admit again
z
Queuing priority: P
queue
= T
max
–
T
elapsed
T
max
is the maximum time in the queue, default value is 5s
IAC – Directed Retry based on Load
Balance
z
Service will be set up to the cell with lightest load
zThe 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
Parameters for IAC Algorithm Switch (1)
z
IU_QOS_NEG_SWITCH (Switcher for IU QoS Negotiation)
Value range: 0 (close), 1 (open)
Default value: 0
z
RAB_DOWNSIZING_SWITCH (RAB Downsizing Switch)
Value range: 0 (close), 1 (open)
Parameters for IAC Algorithm Switch (2)
z
PREEMPTALGOSWITCH (Preempt algorithm switch)
Value range: On, Off
Default value: Off
z
QUEUEALGOSWITCH (Queue algorithm switch)
Value range: On, Off
Parameters for RAB Downsizing
z
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
Parameters for Queuing (1)
z
QUEUELEN (Queue length)
Value range: 5 to 20
Recommended value: 10
z
POLLTIMERLEN (Poll timer length)
Value range: 1 to 6000
Physical value range: 10 to 60000 ms step: 10ms
Parameters for Queuing (2)
z
MAXQUEUETIMELENx (Max queuing time length 1~12)
Value range: 1 to 60s
Parameters for DRD (1)
z
DRMAXUMTSNUM (Max inter-frequency direct retry number)
Value range: 0 to 5
Parameters for DRD (2)
z
R99CSSEPIND (R99 CS separation indicator)
Value range: FALSE (no separation), TRUE (separation)
Recommended value: FALSE
z
R99PSSEPIND (R99 PS separation indicator)
Value range: FALSE (no separation), TRUE (separation)
Contents
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)
LCC (Load Congestion Control)
Overload state: OLC will be
used
Load%
TH
LDRTH
OLC100%
section A
section
B
section C
1
2
Normal state: Permit entry
Times
Basic congestion state: LDR
will be used
LDR (Load Reshuffling)
z
Reasons
When the cell is in basic congestion state, new coming calls could
be easily rejected by system
z
Purpose
Optimizing cell resource distribution
Decreasing load level, increasing admission successful rate
z
Triggering of LDR
Power resources, code resource, Iub resources or Iub bandwidth,
LDR Procedure
Mark "current LDR state = uncongested" Wait for congestion indication Congestionstate 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 on Iu interface BE rate reduction Succeed? Mark "current action = successful action" Wait time for LDR action duration Y Y Y Y Y N N N N N N
Mark "current action = first LDR action" No related action can be found
N Inter-system handover in CS domain Succeed? Succeed? Succeed? Succeed? Succeed? Code reshuffling Succeed? Y N MBMS power reduction N Succeed? Y Y
LDR Actions - Inter-frequency Load
Handover
z
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”
z
Target users
Based on user priority and the current service rate
z
Result
The load of two cells is lower than the basic congestion trigger
LDR Actions - BE Rate Reduction
z
Candidate RABs
The data rate of BE service is larger than GBR
z
Target RABs
Rank the candidate RABs by the integrate priority, the low priority
RABs reduce BE rate first
z
Result
Cell load is decreased under basic congestion trigger threshold
LDR Actions - Uncontrolled Real-time
QoS Renegotiation
z
Target RABs
Rank the candidate RABs by the integrate priority, the service with
lowest priority and current data rate higher than GBR will be
selected
z
Result
Cell load is decreased under basic congestion trigger threshold
LDR Actions - Inter-system Handover In
the CS/PS Domain
z
Target user
Based on the integrate priority, sorting the UEs in descending
order. The top CS/PS services are selected
z
Result
Cell load is decreased under basic congestion trigger threshold
WCDMA cell
GSM cell
LDR Actions - AMR Rate Reduction
z
Target user (downlink e.g.)
Candidate RABs: users accessing the AMR services (conversational)
and with the bit rate higher than the GBR
Rank the candidate RABs by the integrate priority, the AMR service
with lowest priority will be selected
z
Result
Cell load is decreased under basic congestion trigger threshold
LDR Actions - Code Reshuffling
z
Purpose
Cell load is decreased under basic congestion trigger threshold
Sufficient code resources can be reserved for subsequent service
3 7 5 SF=4 SF=8 SF=16 SF=32 SF=64 1 2 4 6 SF=128 A B C
LDR Actions - MBMS Power Reduction
z
Purpose
The downlink power load can be reduced by lowering power on
Parameters for LDR Algorithm Switch
z
NBMLdcAlgoSwitch (Cell algorithm switch)
Value Range:
ULLDR, DLLDR, CELL_CODE_LDR, CELL_CREDIT_LDR
Default status: OFF
Most of the LDR actions (except inter-frequency load handover) affect
Parameters for LDR Algorithm Priority
z
Priority for load reshuffling
Value Range:
IUBLDR(Iub load reshuffling), CREDITLDR(Credit load reshuffling),
CODELDR (Code load reshuffling), UULDR (Uu load reshuffling)
Default status:
LdrFirstPri = IUBLDR
LdrSecondPri = CREDITLDR
LdrThirdPri = CODELDR
LdrFourthPri = UULDR
Parameters for Triggering of Power
Resource (1)
z
ULLDRTRIGTHD (UL LDR trigger threshold)
Value range: 0 to 100%
Recommended value: 55, namely 55%
z
ULLDRRELTHD (UL LDR release threshold)
Value range: 0 to 100%
Parameters for Triggering of Power
Resource (2)
z
DLLDRTRIGTHD (DL LDR trigger threshold)
Value range: 0 to 100%
Recommended value: 70, namely 70%
z
DLLDRRELTHD (DL LDR release threshold)
Value range: 0 to 100%
Parameters for Triggering of Code
Resource and Credit Resource
z
CELLLDRSFRESTHD (Cell LDR SF reserved threshold)
Value Range:0, 1, 2, 3, 4, 5, 6, 7
Physical value Range: SF4, SF8, SF16, SF32, SF128, SF256
Recommended value: SF8
z
UL (DL) LDRCREDITSFRESTHD (UL/DL LDR Credit SF
reserved threshold )
Value Range:0, 1, 2, 3, 4, 5, 6, 7
Physical value Range: SF4, SF8, SF16, SF32, SF128, SF256
Parameters for LDR Period
z
LDRPERIODTIMERLEN (LDR period timer length)
Value range: 1 to 86400 unit: second
Recommended value: 10, namely 10s
Parameters for LDR Action Sequence
z
UL (DL) LDRFIRSTACTION (UL/DL LDR First action) ~
UL (DL) LDRSIXTHACTION (UL/DL LDR Sixth action)
Value range: NOACT, INTERFREQLDHO, BERATERED,
QOSRENEGO, CSINTERRATLDHO, PSINTERRATLDHO,
AMRRATERED, MBMSDECPOWER, CODEADJ
Default value: UlLdrFirstAction or DlLdrFirstAction is CODEADJ,
UlLdrSecondAction or DlLdrSecondAction is INTERFREQLDHO
UlLdrThirdAction or DlLdrThirdAction is BERATERED，the other is
NOACT
Parameters for LDR Code Reshuffling
z
MAXUSERNUMCODEADJ (Max user number of code adjust)
Value range: 1 to 3
Parameters for LDR Inter-Frequency
Load Handover (1)
z
ULINTERFREQHOCELLLOADSPACETHD (UL Inter-freq cell load
handover load space threshold)
Value range: 0 to 100%
Recommended value: 20, namely 20%
z
DLINTERFREQHOCELLLOADSPACETHD (DL Inter-freq cell load
handover load space threshold)
Value range: 0 to 100%
Parameters for LDR Inter-Frequency
Load Handover (2)
z
ULINTERFREQHOBWTHD (UL Inter-freq cell load handover
maximum bandwidth)
Value range: 0 to 400000bps
Recommended value: 200000, namely 200kbps
z
DLINTERFREQHOBWTHD (DL Inter-freq cell load handover
maximum bandwidth)
Parameters for LDR Other Actions
zUL (DL) LDRBERATEREDUCTIONRABNUM,
UL (DL) LDRPSRTQOSRENEGRABNUM,
UL (DL) LDRCSINTERRATHOUSERNUM,
UL (DL) LDRPSINTERRATHOUSERNUM,
ULLDRAMRRATEREDUCTIONRABNUM
Value range: 1 to 10
Default value
UL (DL) LDRBERATEREDUCTIONRABNUM:
1
UL (DL) LDRPSRTQOSRENEGRABNUM:
1
UL (DL) LDRCSINTERRATHOUSERNUM:
3
UL (DL) LDRPSINTERRATHOUSERNUM:
1
UL (DL) LDRAMRRATEREDUCTIONRABNUM:
3
Contents
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)
OLC (Over Load Control)
z
Reasons
In overload state, system is not stable
z
Purpose
Ensuring the system stability and making the system back to the
normal state as soon as possible
z
Triggering of OLC
OLC Actions - TF Control
z
Target user
Rank the candidate users by the integrate priority, the low priority
user will be selected
z
Execution
Send the control message to UE (downlink: TF control indication,
uplink: Transport format combination control) to restricts the TFC
selection
After the congestion is released, the BE service rate will be
OLC Actions - Release of Some UEs
z
Target user (downlink e.g.)
Rank the candidate users by the integrate priority, the low priority
user will be selected
z
Execution
Parameters for OLC Algorithm Switch
z
NBMSWITCH (Cell algorithm switch)
Value Range:
ULOLC, DLOLC
Default status: OFF
Parameters for Triggering of Overload (1)
z
ULOLCTRIGTHD (UL OLC trigger threshold)
Value range: 0 to 100%
Recommended value: 95, namely 95%
z
ULOLCRELTHD (UL OLC release threshold)
Value range: 0 to 100%
Parameters for Triggering of Overload (2)
z
DLOLCTRIGTHD (DL OLC trigger threshold)
Value range: 0 to 100%
Recommended value: 95, namely 95%
z
DLOLCRELTHD (DL OLC release threshold)
Value range: 0 to 100%
Parameters for OLC (1)
z
OLCPERIODTIMERLEN (OLC period timer length)
Value range: 100 to 86400000, unit: ms
Parameters for OLC (2)
z
ULOLCFTFRSTRCTTIMES (UL OLC fast TF restrict times)
Value range: 0 to 100
Recommended value: 3
z
DLOLCFTFRSTRCTTIMES (DL OLC fast TF restrict times)
Value range: 0 to 100
Parameters for OLC (3)
z
ULOLCFTFRSTRCTRABNUM (UL OLC fast TF restrict RAB number)
Value range: 1 to 100
Recommended value: 3
z
DLOLCFTFRSTRCTRABNUM (DL OLC fast TF restrict RAB number)
Value range: 1 to 100
Parameters for OLC (4)
z
RATERSTRCTCOEF (DL OLC fast TF restrict data rate restrict
coefficient)
Value range: 1 to 99%
Parameters for OLC (5)
z
RATERSTRCTTIMERLEN (DL OLC fast TF restrict data rate restrict
timer length)
Value range: 1 to 65535, unit: ms
Recommended value: 3000, namely 3s
z
RATERECOVERTIMERLEN (DL OLC fast TF restrict data rate
recover timer length)
Parameters for OLC (6)
z
ULOLCTRAFFRELRABNUM (UL OLC traff release RAB number)
Value range: 0 to 10
Default value: 0
z
DLOLCTRAFFRELRABNUM (DL OLC traff release RAB number)
