nokia-gsm-kpi analysis based on daily monitoring basis-presentation

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KPI ANAL\SISREASONS AND SOLUTONSSome Relations-1- One BSC=6 BCSU (Base controI signaIing unit). One BCSU = support 110 TRX. 1 TRX= 8 time sIots. TotaI no. of TRX = 110 *6=660 TRX in singIe BSC One BSC = One LAC One BSC= 660* 8 = time sIots but if duaI rate is impIemented that it consider as two sIots. One BSC= two Lac aIso but for city one LAC b/c it effects SD bIocking and LAC updation on that channeI.Some Relations-2- One BSC= 1 to 248 BCF. One BSC= 1 to 248 BTS One BTS means = one sector of any configuration One BCF means= one site of three or four sector BCF= Base controI function. BTS= Base transceiver system. NSEI= is hardware and software device which supports the GPRS in n/wSome Relations-3- One NSEI= supports 64 BTS and 128 TRX if any one of them is fuII then we can assign second NSEI port in same BSC 1TRX=117 subscriber 1 subscriber=25 m erIangs (TCH) 1 subscriber=.004 m erIangs(SD) 1 TRX=2.94 erIang(2% GOS ) 2 TRX=8.2 erIang(2% GOS ) 3 TRX=14.6 erIang(2% GOS ) 4 TRX=21.2 erIang(2% GOS ) If BSC 3VI, OSS is 4 and System is S11 then max capacity of BSC is 660 TRXs. If OSS 4.2 and system S12 is using then max capacity of BSC wiII be 2000TRXsKPI`s to be monitored SD Blocking SD Drop TCH Blocking TCH Assignment TCH Drop HOSRParameter Showcase ThreshoIdNon-Showcase ThreshoIdSD BIocking 0.25 0.5SD Drop 1.2 1.7TCH BIocking 0.5 0.5TCH Assignment 98.5 98TCH Drop 1.5 3HOSR 95 92KPI`s to be monitoredet Serviceet SDCCHEstablish SD ChannelEst. TCHConn. Call Phone Ref. PhoneSD BIkingSDCCH SeizerTCH BIkingCSSR or TCH Assignmentall LstablishmentCall completion Rate (TCH Drop call)hat is Dropped all All cell resources are available but calls are failing, then we have a call drop scenario. This could be caused by software errors, congestion, C7 link failures,HW problems or many other reasons. f a call is abnormally disconnected, a Clear Request is sent to the MSC .f the Call is disconnected in a normal Fashion then Clear Message with cause code Call Control is sent. t is important to establish what types of calls are failing, and over what percentage of the network it is occurring.SD ANNLL : SDCCH is a dedicated channel which is using for LAC updation, Call setup, SMS in idle mode. t works in UL & DL.SD Blocking: SD blocking means that you are not getting SD resource for the call origination. When MS connects with NW then RACH and ACH are provided. After ACH,SDCCH is provided but if SDCCH is not provided at this time due some problems or due to unavailable of SD by BSC ,it's called as SD Blocking. There are no of reasons for that.f such a case arises the customer will not be able to originate any call.Difference Between Blocking and Congestion: t is very important to know difference between blocking and congestion. Some people think that both are same, but they differ from each other. f all the SD resources are full and not available for SD assign then its come into congestion. f at a particular time call is attempted and it fails then it known as Blocking.#easons for SD Blocking:Some of them are- LAC boundary. HW Prob.Solutions for removal of SD Blocking: Here are some steps by which we can reduce SD BIocking-. Check the No. of SDCCH channel Available, if less then increase SD channel taking care that there is no TCH Blocking.2. Check LAC boundary, f location update is more then change the LAC of that site and set C2 and HYS.3. Use of Dynamic SDCCH (t is a BSC parameter and will be applied on whole BTS).4. Hardware check / shift SD to new time slot5. Some times BMA and HYS parameters are useful to remove SD Blocking.&sefull #eports Ior SD Blocking: Use 2 to analyses SD Blocking reasons. 30 for SD congestion.SD Drop: As per diagram shows when we assigned SD for call origination and at that time due to some problem or any mismatch comes by which SD loss occurs, it is called as SD Drop. t occurs between allocation of SD and before TCH allocation. Sometimes SD drop occurs because queuing is not activated in the system. f SD drop is high plz look on parameters like-overshooting , shift the SD time slot , may be hardware issue, interference, change the values of RXP, PMAX, may be issue of uplink or downlink issue in that cells for UL put a TMA in that cell and for DL provide tilt ,re orient that antennaI SD Drop is high:If SD drop is high pIz Iook on parameters Iike- Overshooting Shift the SD time slot Hardware issue nterference Change the values of RXP PMAX t may be uplink or downlink issue in which cells for UL put a TMA in that cell and for DL provide tilt Re orient that antennaReasons o SD Drop: Hardware Fault. nterference. MAO mismatch. Bad Coverage. High TR Fail. Outage. Overshooting. Abis Drop. High Path Loss. Wrong Parameter Planning. Due to CM Band(CDMA) High LAPD Utilization Heavy blocking and DR feature being used extensivelySolutions or remoal o SD Drop:Interference: Check the BCCH Plan (C/ or C/A). Co-BSC & Co BCCH. Use latest ND and Mapnfo to find out proper frequency to reduce interference.Arrange Drive Test: The best way to find the real issues for nterference makes DT. Check interference by nterference scanning. Check clean BCCH by frequency scanning.vershooting: LAC Planning. f a cell is picking call from long distance, Check the sample log according to TA. Cell orientation need to be defined according to clutter. Mount position Effective Tilt.ont.High TR Fail: Check and clear TR fail from OSS end.Bad Coverage: f the drop call is due to low signal strength uplink, check the receive path of this particular TRX. Check receiver sensitivity, VSWR, feeder connection and etc. Drops due to Low Signal Strength. f the drop call reason is due to low signal strength downlink, then, check the transmit path. Check cards, feeder and etc. Use Mapnfo or oogle Earth to find location of sites.ont..High LAPD UtiIization: Check LAPD util report from OSS, and define 32 kbps signaling instead of kbpsHardware FauIt: Check Alarms. TRX condition. Check Path mbalance. VSWR of the Cell. Connector Connection. Some times you will find issues on BCCH TRX.n this case BCCH shift from one to other TRX will reduce SD drop.ont.Due to ICM Band(CDMA): Some time SD drops takes place due to near sites of CDMA. Check the CM band value of that site. Use BPF (Band pass filter). Use the spectrum analyzer.ont..Check for parameter: Check the Timer T 30 Check the Timer T 200(20ms) T Expired(0 s) MAO check.&seul Reports or SD Drop: Use report ZEOL to find the alarms. Use 20 for Path loss analysis. Use for UL-DL nterference. Use 3 report for SD drop. Use report 2 for detail SD Drop. 232 report for TA report. 2 for Adj cell having same or adj freq. ND for freq plan. 204 for BTS and cell report.%CH Blocking: hen TCH is not aIIocated to the user after SD aIIocation ,it is TCH BIocking. It is the faiIed caII attempts which the MS user can notice. It takes pIace due to Iack of TCH Resource.Reasons or 1 Blocking:Some of them are- High Utilization of TCH Time slot faulty. Lock TRXs. HW Problem.Solutions or remoal o 1 Blocking: mplement half rate or Dual rate. Check FRL & FRU. Add another TRX. f TRX addition not possible, try to share the traffic of that cell with the neighboring cell by changing tilt or orientation.&seful #eport for %CH Blocking: 135 TCH Congestion%CH Assignment: t's a process of by which TCH is assigned to the MS. After the SD request MS gets TCH successfully and the call transfers to TCH it means TCH assignment is successful. For the best KP TCH assignment should tend to 00%. t degrades due to HW problems.Reasons or 1 Assignment ailure: Hardware Fault(TRXs,Combiner,Duplexer,Cables) VSWR High Path Loss. Faulty TMA. High TCH Blocking. Loose connections. DR being used extensivelySolutions or remoal o 1 Assignment: Clear VSWR F TRXs are faulty lock them and try to replace them soon to avoid blocking Path mbalance clear. Connection from BTS to Antenna Connector connection Check TMA. Check Duplexer,Combiner,TRXs connections,Multicuppler etc. Check BOA card. Check BB2F Card.#eports for %CH Assignment: ZEOL to check alarms 20 for path imbalance for UL-DL interference ZAHP for Flick report1 Drop: Drop during conversation is known as TCH drop. t takes place after connect ACK msg on TCH.TCH drop occurring. For TCH drop first cross check the BCCH of that cell, hardware issue may be, change RXP and RLT value. Find out there is any interference ,neighbor defined.Reasons or 1 Drop: Wrong Parameter Planning. BAD HOSR. Hardware Fault. High TR Fail. Overshoot. Outage. Due to Low Coverage. Due to CM Band(CDMA)Solutions for removal of %CH Drop:Check Parameter: Check the BCCH Plan (C/ or C/A). Co-BSC & Co BCCH. Check the Timer T 00(should be 20 ms)Check Overshooting: f a cell is picking call from long distance, Check the sample log according to TA.. Site Orientation. Effective tilt should be check. Mount position should be checkont..Improve HOSR: Check the Hopping plan. Check the Neighbor PlanHigh TR Fail: Check and clear TR fail from oss end.ont..Bad Coverage: f the drop call is due to low signal strength uplink, check the receive path of this particular TRX. Check receiver sensitivity, VSWR, feeder connection and etc. Drops due to Low Signal Strength. f the drop call reason is due to low signal strength downlink, then, check the transmit path. Check cards, feeder and etc. Use Mapnfo or oogle Earth to find location of sites. Effective tilt should be check. Mount position should be check. ont..Check H: Check Alarms on site. Check TRXs. Check Slips. Check the Hopping plan. Check BB2F card. Check VSWR, Path imbalance. Connector Connection. Check TMAont..Drop Reason because of H Issues: if drops are only on one