call setup establishment success rate optimization process
TRANSCRIPT
1- RRC Establishment Success Rate optimization process
VS.RRC.Reject
.Redir.Intrat
important
Start
Go to capacity
management
actions in the
related section
for UL/DL
capacity
management
RRC setup
Success rate
<= 99,5% (to
define)
End
True
VS.RRC.Rej.RL
.Fail
important
VS.RRC.Rej.A
AL2.Fail
important
(Related to
ATM trans)
VS.RRC.Rej.DL
.CE.Cong
important
RRC.FailConn
Estab.Cong
important
VS.RRC.Rej.UL
.CE.Cong
important
VS.RRC.Rej.Po
wer.Cong
important
VS.RRC.Rej.Co
de.Cong
important
RRC.FailConn
Estab.NoRepl
y important
VS.RRC.Rej.Re
dir.Inter.Att
important
VS.RRC.Rej.Re
dir.Inter.Att
important
1-Check hardware problems of NodeB (check alarms) 2- Restricted number of CEs on NodeB. (check if high CE usage) 3- WBBP processors overload (check WBBP, UMPT loads)
1- Limited AAL2 ressources (check usage rate) 2- cells problems (check alarms) 3- configuration mismatch
1- Check cell coverage and selection, reselection parameters. 2-Change PRACH procedure in order to increase probability of PRACH decoding:
Change AICH power from -12 to -6 dB
Change FACH power from -1 to 1 dB
Change PRACH power ramp param
Is not a real rejection but a rejection consequence (redirection of rejected request). Find original cause from the other described in this document). Note that interRAT redirection for congestion cause need to be minimal if not nul in order to keep max users in 3G.
False
2- CS RAB Establishment Success Rate optimization process
Start
Go to capacity
management
actions in the
related section
for UL/DL
capacity
management
CS RAB
setup
Success
rate <=
98%
End
True
VS.RAB.FailEs
tabCS.RNL
important
VS.RAB.FailEs
tCS.Relo
important
VS.RAB.FailEs
tCs.Code.Con
g important
VS.RAB.FailEs
tCs.Power.Co
ng important
VS.RAB.FailEs
tCs.DLCE.Con
g important
VS.RAB.FailEs
tCs.ULCE.Con
g important
VS.RAB.FailEs
tCs.IUB.Band
important
VS.RAB.FailEs
tCS.RIPFail
important
VS.RAB.FailEs
tCS.Unsp
important
VS.RAB.FailEs
tabCS.TNLimp
ortant
Is related to radio problem, including all of the next points + radio coverage problems. Global counter includes many of the next counters.
If value is important, make a check on RNC borders and change the reselection/Handover parameters to reduce reselection and handover to/from the current RNC. Change interRNC strategy from Relocation to DSCR or reduce HO between RNCs.
Due to RB failure. Check RB failure cause for detailed analysis. Mainly due to radio interface quality and coverage
Related to QoS definition problem between CN and RAN. Includes following subcauses: Requested Traffic Class not Available (18), Requested Maximum Bit Rate not Available (20), Requested Maximum Bit Rate for DL not Available (33), Requested Maximum Bit Rate for UL not Available (34), Requested Guaranteed Bit Rate not Available (21), Requested Guaranteed Bit Rate for DL not Available (35), Requested Guaranteed Bit Rate for UL not Available (36), Requested Transfer Delay not Achievable (22)
False
Includes two subcauses: Signaling Transport Resource Failure(65) Iu Transport Connection Failed to Establish(66). Check transmission quality and capacity at Iu interface required
3- PS RAB Establishment Success Rate optimization process
Start
Go to capacity
management
actions in the
related section
for UL/DL
capacity
management
PS RAB
setup
Success
rate <=
98%
End
True
VS.RAB.FailEs
tPS.Parimport
ant
VS.RAB.FailEs
tPS.Reloimpo
rtant
VS.RAB.FailEs
tPs.Code.Con
g important
VS.RAB.FailEs
tPs.Power.Co
ng important
VS.RAB.FailEs
tPs.DLCE.Con
g important
VS.RAB.FailEs
tPs.ULCE.Con
g important
VS.RAB.FailEs
tPs.IUB.Band
important
VS.RAB.FailEs
tPS.RIPFailim
portant
VS.RAB.FailEs
tPS.Unsp
important
VS.RAB.FailEs
tabPS.TNLimp
ortant
Verify traffic handling and QoS parameters between CN and RAN. Includes: Invalid RAB Parameters Value, Invalid RAB Parameters Combination, Condition Violation for SDU Parameters, Condition Violation for Traffic Handling Priority, Condition Violation for Guaranteed Bit Rate.
If value is important, make a check on RNC borders and change the reselection/Handover parameters to reduce reselection and handover to/from the current RNC. Change interRNC strategy from Relocation to DSCR or reduce HO between RNCs.
Due to RB failure. Check RB failure cause for detailed analysis. Mainly due to radio interface quality and coverage
False
Includes two subcauses: Signaling Transport Resource Failure(65) Iu Transport Connection Failed to Establish(66). Check transmission quality and capacity at Iu interface required
Related to QoS definition problem between CN and RAN. Includes following subcauses: Requested Traffic Class not Available (18), Requested Maximum Bit Rate not Available (20), Requested Maximum Bit Rate for DL not Available (33), Requested Maximum Bit Rate for UL not Available (34), Requested Guaranteed Bit Rate not Available (21), Requested Guaranteed Bit Rate for DL not Available (35), Requested Guaranteed Bit Rate for UL not Available (36), Requested Transfer Delay not Achievable (22)
4- RB Establishment Success Rate
Start
RB setup
Success
rate <=
98%
End
True
VS.FailRBSetu
p.CfgUnsupim
portant
VS.FailRBSetu
p.PhyChFaili
mportant
VS.FailRBSetu
p.IncCfgimpor
tant
VS.FailRBSetu
p.NoReplyimp
ortant
VS.FailRBSet
up.CellUpdim
portant
This is due to maloperations by subscribers. No action required.
Should be very low
False
This is a common cause of RB setup failure. Related to mal
operation of UE.
Cell update occurs during RB setup. It seldom occurs.
Physical channel failure: It seldom occurs. Related to quick
interference increase, rapid field drop, …
Make RF actions in order to correct coverage and/or make
dominant cell and/or make faster handover to best cell.
VS.RRC.Reject
.Redir.Intrat
important
5- Capacity management
a. DL power
True
False
FACH load >=
30%
Accessibility KPIs under threshold
or congestion or throughput per
user low (DL branch)
TCP usage
>=80% or
power cong>=
1%
End
DL L2+
Power margin optimization
Reduce RRC related to
IRAT
Non-HS TCP
>= 50%
Periodic LAU and RAU
parameters
Reduce RRC related to
REG
Enable EFD feature
True
FACH UE power control
Add S-CCPCH
Change and optimize cell
transition timers and
parameters (4A,4B, …)
Is RRC load
heavy True
False
True
Load based LDR actions
R99 load >=
50% of cell
load
False
Change Power preferred
or power/code balancing
strategy at NodeB
Enable HS-SCCH less
operation feature
CCH load
>=20%
CCH PO optimization
True
False
Check other congestion
causes
True
Add DL power capacity if
license ok and/or add PA
or RFU if hardware limited
Check RF and equipment.
Check related section.
False
b. UL power
Accessibility KPIs under threshold
or congestion or throughput per
user low (UL branch)
Is RTWP >= -
100 dBm Check other congestion
causes
Check RF and equipment.
Check related section.
RTWP >=-
100 and
small
number of
users
Activate LDR actions
Enable auto adaptative
Background Noise
Change Background Noise
according to situation
Interference
troubleshooting
Increase target load
R99 load >=
50% of cell
load
Enable CCPIC feature
HSDPA
accompagny
traffic >= 30%
of cell load
CQI feedback period
optimization
Is RRC load
heavy
Reduce RRC related to
IRAT
Periodic LAU and RAU
parameters
Reduce RRC related to
REG Enable EFD feature
Is HSUPA load
heavy
HSUPA data channel
power adaptation
PO optimization
HSUPA adaptative
retransmission
Disable TTI 2ms license or
2ms/10ms switching
based on RTWP
UL/DL L2+
Enable CPC DTX feature
RACH load >=
30%
RACH parameters
optimization
Number of UE
limited in
power
important Coverage based E2D
Coverage based TTI
2ms/10ms switching
True
False
End
c. Other congestion:
Accessibility KPIs under threshold
or congestion or throughput per
user low (UL branch)
Is power
problem
UL ENU ratio
>= 70% and/
or ENU >=
150
HSUPA active
users >= 85%
Max
supported/auth
orized users
UL Iub
congestion >=
1%
CNBAP
utilization ratio
> 60%
andRLfailure
exists
NodeB UL
physical/licens
e usage >=
70% and/or DL
CE cong>= 1%
Modify max Equivalent
user number per cell
Modify max number of
HSUPA users per cell
Enable/check if enabled
dynamic CE license
CE based TTI 2ms/10ms
switching
Add CE license in NodeB
and if required expand
RNC total and/or WBBP
Activate LDR actions
CE overbooking Activation
Ressource group
adjustment
GBR adjustment
Iub overbooking
Add Iub transmission
capacity
Disable TTI 2ms/10ms
Transmission troubleshooting Add board: according to
case WBBP, UMPT
UL Iub
congestion
duration >= 1%
and UL Iub
usage <= 70%
Check graph for power
False
End
Check graph for power
6- RF/equipment check process:
End
Start
Alarms troubleshooting
RF optimization: azimuth
change, tilt change, CPICH
change.
Neighboring optimization and
chek (relations, strategy, CIO,
idleoffset2sn, …)
Add NodeBs and/or carrier
and/or sector
Is cell
coverage
reasonable
Problem
solved
Problem
solved
Cell has
alarms
Problem
solved True
False False
True
False True