网优疑难试题.docx
《网优疑难试题.docx》由会员分享,可在线阅读,更多相关《网优疑难试题.docx(8页珍藏版)》请在冰豆网上搜索。
网优疑难试题
无线接入信道属于随机和突发干扰并存的变参信道,因此一般都要使用差错控制编码技术以保证数字信令和信号的可靠传输。
B 是其主要采用的差错控制方式。
A.ARQ B.FEC C.BCH-------FEC前向纠错编码
一个功率为20dBm的输入信号经过一个4功分器后,它的信号强度变为:
D
A.23dBm B.17dBm C.15dBm D.14dBm4功分相当于信号衰减为原来的1/4,衰减1/2为3DB.
天线方向图是由多少数量波瓣组成。
D
A.1个 B.2个 C.3个 D.多个
设定两个频率f1,f2,下列哪种情况属三阶互调 B
A.f1-f2, B.2f1-f2, C.3f1-f2
测量信号标准阻抗为:
A
A.50欧姆 B.75欧姆 C.120欧姆
1个2M传输不用信令压缩的情况下最多可以开通几个载波:
B
A.9个 B.10个 C.12个 D.15个
在切换中,“HANDOVERPERFORMED”这条消息是从 D 的。
A.MSC发向BSC B.BSC发向MSC C.MS发向BSC D.BSC发向MS
TheSS7signalingismadeupofaMassagePart(MTP)andanumberofUser/ApplicationParts(UP).WhatUserorApplicationPartisusedforsignalingbetweentheBSCandtheMSCintheGSMnetwork?
B
A.MAP B.BSSAP C.OMAP
WhatpartwasaddedtotheMTPintheSS7signalingsystemtoenableittosupportconnection-orientatedandconnection-lesssignaling?
A 正确答案应该是C
A.ISUP B.TCAP C.SCCP
CALLCONFIRMEDisasignalsentfromtheMStotheMSCforthepurposeof?
A
A.RespondingtoSETUPsignalfromtheMSC B.RespondingtotheAUTHENTICATIONREQUESTsignalfromMSC C.RespondingtothePAGINGCOMMANDfromtheMSC
WhichofthefollowingisusedbytheBTSandMSinprovidingsecurityforthespeechanddataovertheairinterface?
B
A.K1 B.Kc C.SRES
WhyisTMSIused?
B
A.Asatemporarypersonalcodetoaccessthenetwork B.Forsecurityreasons C.Forusewitharentedmobiletelephone
TimersareusedforPeriodicLocationUpdating.Wherearethesetimerslocated?
a
A.A)MSandMSC B.B)MSandBSC C.C)BSCandMSC
HowmanyTSsandE1sarerequiredtoconnectthefollowingaccessnetworktoaBSCwhenaDXCisusedtogetmaximumutilizationoftheE1s?
Accessnetworkwith30sitesoftype3/3/3and20sitesoftype2/2/2.LAPD-multiplexingandLAPD-concentrationisused. C
A.870TSs,29E1s B.848TSs,28E1s C.780TSs,26E1s
Whatisthedifferencebetweenmessagetransferona)MTPandb)SCCPlevelinSTP?
A.a)GTTisinSTP,b)noGTTinSTP B.a)noGTTinSTP,b)GTTinSTP C.nodifference
CalculatethesignalingvolumegeneratedontheAinterfaceinthePLMNshownbelow
Inputdata:
50000subscribers,trafficpersubscriberis25mE,MHT=100s,numberoflocationupdates=1per/subscriber/busyhour,octets/call(toBSC/TRC)=270,octets/call(fromBSC/TRC)=280,octets/locationupdating(to,BSC/TRC)=130,octets/locationupdating(fromBSC/TRC)=87. A
A.79,1kbit/s B.42,4kbit/s C.41,4kbit/s
Blockingsupervisionmeasurementstakeplaceevery A
A.100sec B.90sec C.60sec D.30sec E.25sec
HowmanyTRXscantheEricssonBSCsupport?
D
A.128 B.256 C.512 D.1020 E.1024
1毫瓦与1瓦约相差多少?
B
A.20dB B.30dB C.1000dB D.100dB
Whatisthenameofthetypeoffadingwhichisduetoshadowing?
D
A.Multipath B.Atmosphericfading C.Rayleighfading D.Log-normalfading E.Pathloss
Whatisthemostcommonvalueofthehysteresisusedwhenestimatingmarginsforlog-normalfading?
A
A.3dB B.5dB C.6dB D.8dBThepurposeoframpingistoavoidhandoverdecisionstoanewneighborbasedononlyafewsamples.Whatisacommonparametersettingformacrocells?
D
A.SSRAMPSI=10andSSRAMPSD=20。
B.SSRAMPSI=10andSSRAMPSD=10。
C.SSRAMPSI=5andSSRAMPSD=2。
D.SSRAMPSI=2andSSRAMPSD=5。
从统计发现某小区掉话率偏高,仔细分析其掉话原因,发现弱信号掉话率占近100%,那么以下分析错误的是 D 答案应该是C
A.该小区可能漏定义了重要邻区 B.该小区可能覆盖太远 C.该小区的ACCMIN设得太低 D.该小区有硬件故障
MAIO是为了减小频率干扰的,分为人工配置和缺省配置。
哪一种复用形式建议采用人工配置的:
C
A.1/3 B.3/9 C.1/1
HowmanyTSsandE1arerequiredfortrafficontheAatrinterfacewhenthetraffictobesupportedis710ErlangandGoS=1%
A.738TSs,24E1s B.185TSs,6E1s C.683TSs,23E1s
WhichofthefollowingSignalingSystemNo.7Protocolsareusedforroutingofsignalingmessages?
B
A.MAP,TCAP B.TCAP,SCCP C.MTP,SCP
1.Calculatetheprocessorcapacityintermsofcalls/swhenthetrafficloadis72%andtheloadpercallis25ms.
A.28,8calls/s B.31,4calls/s C.33,8calls/s
Whichofthesedifferent“droppedcallrates”givesa“subscriberperceived”droprate?
B
A.DroppedTCHconnectionsofthetotalnumberofTCHconnections B.Droppedcallsofthetotalnumberofcallsterminatedinthecell C.ErlangminutesperdroppedTCHconnection D.Averagecalldropsexperiencedduringonehourtalktime E.Allofthese
WhatisaddedtotheMSsensitivityleveltoobtaintherequiredsignalstrength,SSreq?
C
A.Rayleighfadingmargin B.Rayleighfadingmarginandinterferencemargin C.Rayleighfadingmargin,interferencemargin,andbodyloss D.Rayleighfadingmarginandbodyloss E.Interferencemarginandbodyloss
UsetheenclosedErlangTabletoworkoutwhichistheoptimumSDCCHconfigurationusingfourTRXs,iftheSDCCH/TCHtrafficratiois30%andtherequiredGoSontheTCHis2%.(AssumenocellbroadcastandnoimmediateassignmentontheTCH.) C
A.SDCCH/8 B.SDCCH/8+SDCCH/4 C.2*SDCCH/8 D.2*SDCCH/8+SDCCH/4 E.3*SDCCH/8
AGBLKmustbesettoanon-zerovalue(thatis=1inEricsson’sGSMsystem),if:
A
A.Cellbroadcastisusedinacellwithanon-combinedconfiguration. B.Cellbroadcastisusedinacellwithacombinedconfiguration. C.Systeminformation,type4,issentontheBCCH. D.Systeminformation,type5,issentontheBCCH. E.MFRMS=2orMFRMS=9
2.WhichisthemostimportantfactorfordeterminingthepagingcapacityintheBTS?
D
A.MFRMS(controlsthenumberofpaginggroups) B.AGBLK(reservesapagingblockforaccessgrant) C.Pagingstrategy(forexample,secondpageintheMSCserviceareaorintheLA) D.Combinedornon-combinedmapping E.Theuseofcellbroadcast
!
AretheULsignalstrengthmeasurementsusedinthelocatingalgorithm?
E
A.Yes,ofcourse. B.No,notatall. C.Yes,butitisusedonlytocheckifconditionsforintra-cellandurgencyhandoversarefulfilled. D.No,itisusedonlyforpowercontrolofthemobile. E.Yes,butitisusedonlytocheckiftheconditionsforintra-cellhandoverarefulfilled.
WhatisthebasicrankingintheEricsson1locatingalgorithmbasedon?
A
A.Relativesignalstrength B.Absolutesignalstrength C.Minimumsignalstrength D.Sufficientsignalstrength E.Quality
WhatisthepurposeofsettingBSRXSUFFto–150dBmandMSRXSUFFto0dBminallcells?
D
A.Tomakesurethattheuplinksignalstrengthinfluencesthebasicranking. B.Toenablepathlossranking. C.Toensurethatthesignalstrengthontheuplinkisalwayssufficient. D.Toobtainanabsolutesignalstrengthranking. E.Todisablepathlossranking.
Cellsinthebasicrankinglistaredividedintocategories.Howmanycategoriesarethere,iftheservingcellisconsideredasacategoryofitsown?
B
A.2 B.3 C.8 D.10 E.11
Whatisoneofthedifferencesbetweenthephase1andphase2establishmentcauses?
D PHASE1不能支持起呼的呼叫与SMS.其它类型的接入可区别
A.Phase2establishmentcausesdistinguishbetweenanswertopagingandcallre-establishment. B.Phase2establishmentcausesdistinguishbetweenMSoriginatedcallandanswertopaging. C.Phase2establishmentcausesdistinguishbetweenlocationupdatingandanswertopaging. D.Phase2establishmentcausesdistinguishbetweenMSoriginatedcallsandSMS. E.Phase2establishmentcausesdistinguishbetweencallre-establishmentandSMS.
WhichofthecriteriabelowisnotinfluencedbythevalueofCHAP?
A (影响用户信道分配的功能是微分信道分配,用于做品牌接入)
A.Prioritizingofdifferentusersornot. B.ImmediateassignmentontheTCHallowedornot. C.TCHorSDCCHfirst. D.Overlaidsubcellasalastresortornot. E.Phase1orphase2mobiles
3.Ifthepathlosscompensationparameter,LCOMPDL,issettoten,thedownregulationintheBTSoutputpower,duetopathlosscompensation,islimitedto:
A
A.6dB B.10dB C.12dB D.20dB E.30dB
4.Assumethatthereare12frequencies(f1-f12)inthehoppingfrequencyset.WhatdefaultMAIOvaluesareallocatedtothefirstsevenTRXsinthecell”?
C
A.0,1,2,3,4,5,and6 B.1,2,3,4,5,6,and7 C.0,2,4,6,8,10,and1 D.1,3,5,7,9,11,and0 E.0,3,6,9,1,4,and7
WhatisnottakenintoaccountwhenderivingSQI?
E
A.BER B.FER C.HOevents D.Speechcoder E.Timingadvance
WhichdropcounterissteppedwhenacallisdisconnectedbecauseMAXTAisexceeded?
E (TA掉话原因是与TALIM比较,大于MAXTA的掉话为不明原因掉话)
A.SSdropcounter B.Qdropcounter C.TAdropcounter D.Allofthese E.Noneofthese
5.Whatexpressionisusuallyusedforthepagingsuccessrate?
D
(PAGING成功率为(第1次+第2次寻呼成功数)/第1次寻呼申请,因为第二次寻呼申请是重复第一次的)
A.Successfulrepeatedpageattempts(inlocationarea)oftotalnumberoffirstandrepeatedpageattempts(inlocationarea). B.Successfulrepeatedpageattempts(inlocationarea)oftotalnumberofrepeatedpageattempts(inlocationarea). C.RateofdiscardedpagingmessagesintheBSC. D.Successfulfirstandrepeatedpageattempts(inlocationarea)oftotalnumberoffirstpageattempts(inlocationarea). E.Successfulfirstandrepeatedpageattempts(inlocationarea)oftotalnumberoffirstandsecondpageattempts(inlocationarea).
如果将T3101设置抬高,可能会造成什么影响?
A
A.riskofSDCCHCongestion B.riskofPCHCongestion C.riskofTCHCongestion D.riskofAGCHCongestion
‘CallProceding’是在以下哪个过程中被用到?
A
A.MOC B.MTC C.LocationUpdate D.handover
Whichofthefollowingstatementsabouttheurbanmodelisnottrue?
D
A.Permanentscreens,usedinthehalf-screenpartoftheurbanmodel,areusedtodefinetheenvironmentalongthecalculationprofileinageneralwayand,therefore,thelo