Major Steps to Improve KPI !!!

Here are some parameters which highly effects network performance like -

• Network Overall ASR (Answer Seizure Ration).
• Location Update Success Rate.
• Paging Success Rate.
• Handover Success Rate.

 & these parameters needs to be monitored continuously for smooth functioning of mobile network.

Network Overall ASR - This is very-very important parameter in telecom industry because it directly relates to Revenue (Money), So we need to keep close monitoring & take certain precautions to keep it higher-n-higher.
Its standard value lies between 35% - 45% & rest % is left considering Subscriber Behaviour i.e. miss call, no answers after long ring, etc.

Points to be closely monitoring for improvement of ASR :-

1. POI Utilization (whether more E1's are required or not).
2. Routing of Levels.
3. Selection of Routes.
4. CIC (Circuit) Hunting e.g. Odd-Even Selection or Sequential Routing.
5. Unallocated Numbers, e.g. subscriber which are churn (De-active), delete those numbers on regular basis.
6. Proper Announcements, so that Subscriber won't re-attempts again n again.
7. CIC matching should be there with other operator.
8. Network Equipment like MSC, etc. should not be congested n Many more......

Location Update Success Rate - It is Number of Successful Location Updates w.r.t. Total Number of Location Updating Attempts. This parameter is calculated for 24 Hrs. Its standard value >= 95%.

LUSR = 100*(Number of successful location updates) / (Total number of location updating attempts)
Where above both paramteres are considered for Non-Registered Mobile Subscribers & Already Registered Mobile Subscribers.

Major contributor for decreasing LUSR -

1. Congestion in C7 Signaling.
2. Incorrect IMSI definition of IMSI analysis in Switch.
3. Incorrect roaming subscriber definition in Switch.
4. SDDCH Congestion.
5. LU timers setting.
6. Network Synchronization problem.

Improvement Plan -

1. Continuous Monitor of C7 Signaling utilization and it should be optimize as much as possible.
2. Correct definition of IMSI and Roaming Subscriber.
3. For Narrow Band Signaling the utilization should not go above 0.3 Erl. & for High Speed Signaling the utilization must be kept below 0.4 Erl(Per time slot).

Paging Success Rate - It is rate of successful page responses to First and Repeated Page Attempts to a location area w.r.t. Number of Initial and Repeated Page Attempts to a location area. This parameter is calculated for 24 Hours. Its standard value >= 92%.

LSR = (Number of Page responses to first page to an LA + Number of Page responses to repeated page to an LA) / Number of Page Attempts to an LA (Location Area).
                                          OR
LSR = (first paging response+ repeated paging response)*100/first paging request).

Major contributor for decreasing PSR -

1. Improper Paging / LU (Location Update) related parameter setting.
2. O&M issue i.e Outages.
3. Lower RACH success rate.
4. Air Interface Issues like Interference, SDCCH Congestion, etc.
5. Footprints.
6. Paging overload on BSC i.e. paging capacity of BSC compared with the actual paging.
7. Congestion on A-bis interface i.e. Paging command from BSC is delivered to BTS via A-bis.

Improvement Plan -

1. Paging / LU timers setting, like Paging Timers in MSC must longer than Paging Timer in BSC (prolonging 1st and repeated page) and also paging strategy (local vs global), or repeated page on/off.
2. LAC optimization.
3. Paging / LU related parameter setting like increasing paging capacity through uncombined BCCH, changing Access grant and MFRMS (multiframe) parameters.
4. Address Coverage issues.
5. Check Discard/Paging queue on cell level.

HandOver Success Rate - It is the mechanism that transfers an ongoing call from one cell to another as a user moves through the coverage area of a cellular system.
             The handover success rate shows the percentage of successful handovers of all handover attempts. A handover attempt is when a handover command is sent to the mobile.

HOSR = (Successful Incoming Inter-Cell Handover + Successful Outgoing Inter-Cell Handover) / (Incoming Inter-Cell Handover + Outgoing Inter-Cell Handover)

Major contributor for decreasing HOSR -

1. C/I Ratio (Carrier-to-Interference ratio), Lower value gives Worst Connection Quality.
2. High Interference, Co-Channel or adjacent i.e., High Bit-Error Ratio.
3. Bad Antenna Installation.
4. Bad Radio Coverage.
5. Incorrect Locating Parameter Settings.
6. Insufficient Planning in Certain Areas.
7. Repeated Handover between two base stations, caused by rapid fluctuations in the received signal strengths from both base stations.
8. Un-Necessary Handover often leads to Increased Signaling Traffic.

Improvement Plan -

1. Updating & Optimising Neighbours List.
2. Removing Neighbours which have fewer no of HOs and cells having poor HOSR,
3. Avoid same BCCH+BSIC Combination.

More Information from Readers are Expected !!!


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