Case 1: Drop due to missing neighbor  Problem: Detected Nighbor (DN)
Mobiloe Station sends a Report ,which it measured in site ,that contains event 1A means adding a new RL (cell) to Active Set
The reported cell should be present in current neighbor cell list,If it not available means and then reported Ec/No is better than the best serving cell Ec/No in AS by some dBs (set by a RNC parameter)
In any movement,new cell can not be added to Aativr Set,if we addd means ,call will be released
Figure : Drop -due -to -missing- neighbor
Case 2: Drop due to Poor Coverage (low RSCP) Â Problem: Poor DL coverage
When Mobie Station have a low RSCP value ( < -107 dBm).At the time Ec/No values,call Drop will happen,Mobilw Staion will likely lift up up the transmitted power and reach its max power. The DL BLER will probably increase and SIR
Figure : Drop -due- to -Poor -Coverage Case 3:Due to Poor DL Coverage
If Mobile Station enters into a RSCP level (< – 105 dBm ) means ,it have low coverage area at the time (.The packet connection is carried on a 64/64 DCH Channel
as consequence of the low coverage conditions.
The UE is Lift up the Mobile Station power to the maximum,it reach to Idle Mode and theApplication and RLC throughputs go
to zero.
At this point the RAS application will start the Session Timeout timer, if the throughput is not resumed the Session Error event is triggered with cause “session timeout†.
Figure : Session -Error - due -to- Poor Coverage
Optimization in UMTS(3G) network &Tuning in UMTS(3G) network
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Optimization/Tuning of UMTS(3G) network
Some Difference are will come ,While doing optimization and Tuning process in network . During Tuning process in network ;
Site is not on Air ,so there is No traffic in network. Tuning of Network is according to our drive test data
Every thing is done before the Site on Air ,It is about Pre-launch activities During Optimization
Optimization is the Process done after Site On Air,when the customer start to use the network. Optimization is the Process to monitor network performance.
Tuning Process Flow
Tuning Process Flowchart
Figure : Tuning Process Flowchart
Tools For Tuning/Optimization & Data Post Processing TEMS Investigation for WCDMA (Software)
TEMS Scanner (Software + HW) External GPS
User Equipment (UE)
TEMS DeskCat for post processing MCOM3g/Mapinfo
MS Access/Excel based tools
Figure : Optimization/Tuning of UMTS(3G) network  Drive Test Routes
Figure : Drive Test Routes PILOT TUNING
The basic measurements of scanner are
CPICH_RSCPÂ (received signal code power)
CPICH_Ec/No (received energy per chip divided by the power density in the band) RSSI (received signal strength indicator)
use of scanner in network ? we can find feedercable problem we can find Coverage problem
Find Interference problems (overshooting cell, pilot pollution) Find the Missing neighbours
COVERAGE VERIFICATION – Primary Common Pilot Channel Verify P-CPICH detection to minimize coverage holes
P-CPICH RSCP P-CPICH Ec/No
Figure : Level of Signal
CPICH_RSCPÂ (received signal code power) Best Server Signal Strength
Yellow means good(No problem in network) Blue make problems in feature
Figure : Best Server Signal Strength Pilot Ec/No Measurements
Green means good(No problem in network) Blue make problems in feature
Orange is bad
INTERFERNECE
By correlating low Ec/No with high RSCP, areas with high interference can be detected
Figure : INTERFERENCE
INTERFERENCE (RSCP > -90 dBm AND Ec/No < -9 dB)
Figure : INTERFERENCE (RSCP > -90 dBm AND Ec/No < -9 dB)  Primary Common Pilot Channel (P-CPICH) – PILOT POLLUTION
Figure: Primary Common Pilot Channel (P-CPICH) – PILOT POLLUTION
Figure : Overshooting in Site
Primary Common Pilot Channel (P-CPICH) – PILOT POLLUTION High CPICH reception levels from many
Cells, (more than MAX_ACTIVE_SET) P-CPICH RSCP
Figure : Pilot Pollution Rectification
Figure : PILOT POLLUTION Change Proposals
Figure : PILOT POLLUTION Change Proposals Pilot Pollution
Figure : Shows Pilot Pollution (Initial and After Tunning ) UE TUNING
Voice /Video/PS calls Long calls
short calls
Identify problem areas Blocked calls
Dropped calls Delay/Throughput
Short Calls Analysis
make a call and maintain it for some time duration (for 15-60 s)  Call set-up failure and drops of short calls mainly due to: user Equipement Failure
Because of Parameters Setting Due to Coverage Problem Due toInterference
Long Calls Analysis
Make a call and maintain the Call upto drop ( because by this we can check the Retainability performace of network) Drops during long call can be used to identify:
we can identify the Missing Neighbor Relation Coverage Problem
user Equipement Problems Network Characteristics Because of Parameters Setting
KPI Parameters for 3G are following: 1) RRC attempt
2.RRC Failure rate 3.RRC drop rate.
4.RAB CS voice failure rate 5.RAB CS voice drop rate 6.RAB DATA failure rate 7.RAB Data drop rate 8.HSDPA Failure rate 9.HSDPA drop rate 10.SHO failure 11.ISHO failure rate 12.IFHO failure rate 13.EDCH estab failure rate 14.EDCH abnormal release rate.
Various Types of Commands we are using in KPI maintaining 1) RRC Drop RRC_CONN_ACT_FAIL_IU RRC_CONN_ACT_FAIL_RADIO RRC_CONN_ACT_FAIL_BTS RRC_CONN_ACT_FAIL_IUR RRC_CONN_ACT_FAIL_I_CHK RRC_CONN_ACT_FAIL_CIPH RRC_CONN_ACT_FAIL_RNC RRC_CONN_ACT_FAIL_UE RRC_CONN_ACT_REL_UNSPEC_CN RRC_CONN_ACT_COMP
RAB_ACT_FAIL_CS_VOICE_IU RAB_ACT_FAIL_CS_VOICE_RADIO RAB_ACT_FAIL_CS_VOICE_BTS RAB_ACT_FAIL_CS_VOICE_IUR RAB_ACT_FAIL_CS_VOICE_RNC RAB_ACT_FAIL_CS_VOICE_UE RAB_ACT_REL_CS_V_UNSPE_ER_CN 3)RAB Data Failure Rate
RAB_STP_FAIL_PS_INTER_AC RAB_STP_FAIL_PS_INTER_RNC RAB_STP_FAIL_PS_INTER_ANCH RAB_STP_FAIL_PS_INTER_FROZBS RAB_STP_FAIL_PS_BACKG_AC RAB_STP_FAIL_PS_BACKG_RNC RAB_STP_FAIL_PS_BACKG_ANCH RAB_STP_FAIL_PS_BACKG_FROZBS RAB_ACC_FAIL_PS_INTER_MS RAB_ACC_FAIL_PS_INTER_RNC RAB_ACC_FAIL_PS_BACKG_MS RAB_ACC_FAIL_PS_BACKG_RNC RAB_STP_ATT_PS_INTER RAB_STP_ATT_PS_BACKG 4)KPI and Counter.
RAB_STP_FAIL_CS_VOICE_AC RAB_STP_FAIL_CS_VOICE_BTS RAB_STP_FAIL_CS_VOICE_TRANS RAB_STP_FAIL_CS_VOICE_RNC RAB_STP_FAIL_CS_VOICE_FROZBS RAB_ACC_FAIL_CS_VOICE_MS RAB_ACC_FAIL_CS_VOICE_RNC RAB_STP_ATT_CS_VOICE
5)KPI and Counters are:
RRC_CONN_STP_FAIL_HC RRC_CONN_STP_FAIL_AC RRC_CONN_STP_FAIL_BTS RRC_CONN_STP_FAIL_TRANS RRC_CONN_STP_FAIL_RNC RRC_CONN_STP_FAIL_FROZBS RRC_CONN_ACC_FAIL_RADIO RRC_CONN_ACC_FAIL_MS RRC_CONN_ACC_FAIL_RNC
