尋呼分析—PAGINGANALYSIS.ppt

1、PAGING ANALYSIS,AGENDA:,Paging Procedure Paging Capacity Paging Related Parameters Paging Performance Analysis Paging Strategy,PAGING PROCEDURE,PAGING in MSC (1):,Paging Message,Cell Identifier List IE All cells controlled by BSC (no list follows): Paging is done in the complete BSC service area. Li

2、st of LAIs (MCC+MNC+LAC) follows: Paging is done in all cells belonging to the specified location areas. List of CGIs (LAI+CI) follows: Paging is done in all specified cells.,MSC BSC BTS MS Paging (RMMSGPAGING) - Paging Command (RHSENDMSGC) - Paging Request (PCH) - Channel Request (RACH) ,PAGING Pro

3、cedure (1),MSC BSC BTS MS Channel Activation Ack. (RCRECABISMSGC) Imm. Assignment(AGCH) - SABM(Paging Resp.) (SDCCH) Establish Ind. (Paging Resp.) (RMESTINDIC) - CR(Paging Resp.) (RMMSGCOMPLAY3) -,PAGING Procedure (2),Paging Response Message,Complete-layer-3 Message,IF USE TMSI,PAGING in MSC (2):,PA

4、GING in MSC (3):,PAGING CAPACITY,MSC Level:,SAE Congestion,HOW to find out?,STS SAACTIONS Table,WHY limitation? an incoming paging message BSC larger number of outgoing paging commands,BSC Level Limitation:,WHAT are they? Number of RP signals/s: can be sent from CP to the RPs in the TRHs. A paging q

5、ueue(32 position): IMSIs or TMSIs queued and transmitted when resources are available. CP load: CP processor load too high. I.e. CP 25 can handle 9000c/s,HOW to find out? Use “Test System” to find out if any congestion.,WHY ? a paging command BTS to broadcast the page at least once,BTS max no. of pa

6、ges CP allowed send to TRH per second.,SDCCH performance,PAGING PERFORMANCE ANALYSIS,Present paging performance Paging Success Rate = (NPAG1RESUCC+ NPAG2RESUCC)/ (NPAG1LOTOT+NPAG1GLTOT) G14: 96.5% (sts from 12/8) G16: 96.3% (sts from 12/8) Estimate the paging load as above, G14: 26.5% G16: 6.9%,Swit

7、ch Related: 1. Congestion 2. Poor Parameter Setting 3. Poor Paging Strategy 4. Signal between MSC & BSC not stable 5. Poor LU performance,Possible Reasons for poor Paging Performance:,Radio Part: 1. Poor Coverage 2. Too much LU 3. Congestion in BSC or BTS 4. Poor performance of SDCCH 5. Poor perform

8、ance of access 6. Drop call 7. Poor Parameter Setting 8. Signal between BTS and BSC not stable 9. BTS Hardware Fault 10. MS Equipment Fault,Possible Reasons for poor Paging Performance:,1. SAE Check 2. Route data & B table check 3. Exchange properties check Purge Control Function Repeat Global Pagin

9、g Repeat Paging Method Selection Paging Timer Setting implicit detach supervision timer 4. TMSI Usage 5. EOS 400 Tracing 6. Trace if paging send out to BSC and back form BSC,Possible Actions on MSC:,TRH Load check Check PAGLIMIT in exchange property Check for congestion of SAEs Check MFRMS. Check BC

10、CHTYPE ATT Check T3212 timer ACCMIN Setting Check Check SCCP connection to MSC Border line of 2 LA,Possible Actions on BSC:,11. Trace: if the paging message arrive in BSC if the paging congestion if capacity not available if paging is working correctly Request page (MSC - BSC) Page response (MS - BS

11、C),Possible Actions on BSC:,PAGING STRATEGY,Lower MFRMS High Paging Commands to the BTS increases the queuing time, something that leads to an increase of the average time for the paging response. If a page is queued for a too long time in the BTS, the page may be lost due to MSC time supervision ex

12、pire. If the queue is full, there will be pages being thrown away. The drawback is that the MS power consumption is higher. No second page: reduces load in BTS & BSC but positive to page performance. Use TMSI Split LA or move cells out ATT to be set to ON: reduces the paging load in the BTS. Shorter T3212 : reduce the paging load but increase SDCCH traffic. BCCHTYPE = NCOMB : increase the paging capacity.,If MSs LA known in the VLR, the first page is a local page. For the local page,