無線接入成功率介紹及案例

1、 JUAN KANG reviewer: Eric Wang AATD-LTE Radio Access Success Rate OptimizationEricsson Internal | 2015-08-01 | Page 2RRC Connection SETUP Process RRC CONNECTION REQUESTRRC CONNECTION SETUPRRC CONNECTION SETUP COMPLETERRC CONNECTION REQUESTIdle ModeInformation needed to set up SRB1 on DCCHpmRrcConnEs

2、tabAtt +pmRrcConnEstabSucc +pmRrcConnEstabReatt +Connected modeSRB 0SRB 1Ericsson Internal | 2015-08-01 | Page 3The main counters for this scenario are the following:RrcConnEstabSuccRate= pmRrcConnEstabSucc/ pmRrcConnEstabAtt*100%RRC Connection SETUP countersEricsson Internal | 2015-08-01 | Page 4E-

3、RAB Setup Process RRC CONNECTION RECONFIGURATIONRRC CONNECTIONRECONFIGURATION COMPLETEMMEINITIAL CONTEXT SETUP REQUESTIncludes a list of E-RABs to be setuppmErabEstabAttInit +INITIAL CONTEXT SETUP RESPONSEpmErabEstabSuccInit +Authentication and security mode proceduresContains info needed to setup R

4、BEricsson Internal | 2015-08-01 | Page 5ErabEstabSuccRate= (pmErabEstabSuccInit+pmErabEstabSuccAdded)/(pmErabEstabAttInit+pmErabEstabAttAdded)*100%The main counters for this scenario are the following:E-RAB Setup countersEricsson Internal | 2015-08-01 | Page 6Radio access success rate analysis steps

5、RadioAccessSuccRate=ERAB.NbrSuccEstab/ERAB.NbrAttEstab*RRC.SuccConnEstab/RRC.AttConnEstab*100%Radio Access Success Rate Analysis PM counters CTR & MRDrive test & UETR analysischeck alarm& cell statusCheck UL interferenceparameter consistencycheckSTEP1STEP2Ericsson Internal | 2015-08-01 | Page 7 Chec

6、k alarm & cell status LinkFailure , PowerFailure , ServiceUnavailable , VswrOverThreshold , Network Synch Time from GPS Missing ect alarm can affect network KPI Sleeping cell -How to find the sleeping cellCheck PM counters. Massive amount of msg3 (pmRrcConnEstabAtt and pmRrcConnEstabAttReatt) and pm

7、RrcConnEstabSucc=0 after successive S1 Connection failure events Check transport Check UL interference pmRadioRecInterferencePwr ( pmRadioRecInterferencePwr and pmRadioRecInterferencePwrPrb ) pmRadioRecInterferencePwrPucchRadio Access Success RateGreatly affect accessibilityEricsson Internal | 2015-

8、08-01 | Page 8 Parameters consistency check Subframeassignment , specialsubframepattern , timeoffset ，cellbarred qRxlevmin , confOutputPower noOfPucchSrUsers , pdcchCfiMode , noOfPucchCqiUsers maxNrOfPucchPrbsPerTtiAndBbm8Rx( SC 961) maxNrOfPucchPrbsPerTtiAndBbm2Rx(SC959) T300 , T302，tRrcConnectionS

9、etupAnalysis PM counters , CTR & MRpmRrcConnEstabAtt , pmRrcConnEstabSucc , pmErabEstabAttAdded , pmErabEstabAttInit , pmErabEstabSuccAdded , pmErabEstabSuccInitpmRrcConnEstabFailHighLoad , pmRrcConnEstabFailOverload , pmRrcConnEstabFailLicUse Xnow analysis CTR and MR verify coverage ,SIM, UE, eNB o

10、r MME parameter issuRadio Access Success RateEricsson Internal | 2015-08-01 | Page 9LEE0280F7S RadioAccessSuccRate was low and had bad impact on all network KPICheck alarm we found the License was expired .Case study1:Ericsson Internal | 2015-08-01 | Page 10Applied new License for ENB , the RadioAcc

11、essSuccRate returned to normalRrcConnEstabSuccRate in Xnow:Case study1:Ericsson Internal | 2015-08-01 | Page 11Case study2:The high PUSCH interference have bad impact on RadioAccessSuccRate Ericsson Internal | 2015-08-01 | Page 12Case study2:We can see the Geography Statistics of the interference in

12、 Mapinfo . These sites are cover Naval base . We have identified that the interference came from the Military exercises .Naval baseEricsson Internal | 2015-08-01 | Page 13Case study3:LDE42Z000H covers the Golden Sands Attractions . Because of the number of users increased quickly and beyond cell cap

13、acity , the Radio Access Success Rate decreased sharply. Ericsson Internal | 2015-08-01 | Page 14After enlarge the capacity of the cell , the blocking problem was solved and the Radio Access Success Rate returned to normal .Case study3:Ericsson Internal | 2015-08-01 | Page 15Parameters OptimizationO

14、ther methods improve Radio Access Success Rate MO Class AttributeDefaultRecommendedDescriptionEUtranCellTDDpdcchCfiMode23Controls the CFI (Control Format Indicator) used for the control region. EUtranCellTDDnoOfPucchCqiUsers160The number of Channel Quality Indicator (CQI) resources available on the

15、PUCCH channel.EUtranCellTDDnoOfPucchSrUsers64360The number of Scheduling Request (SR) resources available on the PUCCH channel.SC 961maxNrOfPucchPrbsPerTtiAndBbm8Rx636Used to set max number of Pucch Prbs Pairs when 8 Rx antennas are used.SC 959maxNrOfPucchPrbsPerTtiAndBbm2Rx2436Used to set max numbe

16、r of Pucch Prbs Pairs when 2 Rx antennas are used.RrcT3016002000Increase the wait time for RRC Connection Reestablishment Reject and RRC Connection ReestablishmentRrcT30220Wait Time in RRCConnectionReject will be a random value range from 0 to 16 secondSC 1198maxArqRetxRrcReleaseDl02This parameter m

17、ust be set in case there is a big events (like concert)From CR3092,HS85095,Max number of ARQ retransmissions for message RRCConnectionRelease DL.SC 220pdcchLaGinrMargin10030Only suggested to use in heavily loaded cells.SC383maxNrOfPf1UsersPerTtiAndBbm2Rx136240Used to set max number of PUCCH format 1

18、 users when 1 or 2 Rx antennas are used. including SR and ACK.（0-244）SC384maxNrOfPf2UsersPerTtiAndBbm2Rx1725Used to set max number of PUCCH format 2 (CQI) users when 1 or 2 Rx antennas are used.（0-36）Ericsson Internal | 2015-08-01 | Page 16Load balanceThe feature distributes traffic load between inter-frequency (LTE) cells that cover the same geographical area . Users in connected mode are distributed by load triggered inter-frequency handovers.Other methods improve Radio Acc