International Journal of Engineering, Applied and Management Sciences Paradigms, Vol. 22, Issue 01 Publishing Month: March 2015 An Indexed and Referred Journal ISSN (Online): 2320-6608 www.ijeam.com IJEAM www.ijeam.com 117 QOS of Short Call Drive Test Atif Mugdam Jaheldeen1, Dr. Khalid Hamid Bilal2 and Dr. Amin Babiker A/Nabi Mustafa3 1,3Department of Communication, Al-Neelain University, Khartoum, Sudan 2University of Science and Technology, Khartoum, Sudan 1mugdam000@gmail.com, 2dr.Khalidbilal@gmail.com, 3amin31766@gmail.com Abstract Theobjectivesofthispaperistostudyanalyze measureshortcalldrivetestforGSMnetworkto evaluatetheperformanceofQOSofGSMnetwork using teems software program the survey were due for two sectors A&B to introduce log file for short call for mobile Service provider . Keywords:DriveTest,KPI,Teems,GSM, Simulation, short call. 1. IntroductionGSMnetworkusuallycalledascellular network(asthewholecoverageareaisdivided into different cells and sectors) is comprised of a mobileStation(MS)whichisconnectedtothe Base Transceiver Station (BTS) via air interface. Inadditiontootherhardware,BTScontainsthe equipmentcalledTransceiver(TRX),whichis responsible for the transmission and reception of severalradiofrequency(RF)signalsto/fromthe end user [1]. PerformanceProblemsthatoften encountered: - Cell Dragging, Dropped Call,-Ping-Ponging, System Busy, Handover boundary Dropped Calls - Caused by either RF environments or incorrect system parameters. Suggestions:Checkifanappropriateneighbour cell list is defined Check HO parameters existing or new coverage holes Interference, Co-channels, AdjacentchannelsorExternalinterference serving cells might go down, coverage smaller as beforeAbnormalitiessuchascallsetupfailure [2] RX Level: a)IssuesObserved:LowRXlevelmightarise duetofollowingissues:1)Antennaorientation and tilt 2) High VSWR value 3) TX power b)ImprovementMethodologies:Following measuresareusedtominimizetheRXLevel problemsinlivenetwork:1)Physicalcheckof orientationandtilt2)CheckRFconnectorsand RF cables RX Quality: a) Issues Observed: Low RX Quality might arise due to following issues: 1)Interference2)LowRxlevel3)H/Ofailure 4)Assignment failure ratio 5)Hardware problem b)ImprovementMethodologies:Following measuresareusedtominimizetheRXQuality problemsinlivenetwork:1)Defineproper neighbors2)CheckDRXpowerandconnectors 3)CheckBCCHandMAIOfrequency4) Reductionofantennaheight,orientationandtilt 5)Checktheneighborlistanddefinition6) Checktheneighborparameters7)CheckDRX andcheckVSWRandRFcableconnectivity8) Check DRX hardware [3] Duetothemobilityofsubscribersand complexityoftheradiowavepropagation,most ofthenetworkproblemsarecausedby increasingsubscribersandthechanging environment.RFOptimizationisacontinuous processthatisrequiredasthenetworkevolves. RFoptimizationiscarriedoutinorderto International Journal of Engineering, Applied and Management Sciences Paradigms, Vol. 22, Issue 01 Publishing Month: March 2015 An Indexed and Referred Journal ISSN (Online): 2320-6608 www.ijeam.com IJEAM www.ijeam.com 118 improvethenetworkperformancewiththe existingresources.ThroughRFOptimization, theservicequalityandresourcesusageofthe networkaregreatlyimprovedandthebalance amongcoverage,capacityandqualityis achieved [4] 2. Drive Test Setup EverygoodRFdesignafteritsimplementation shouldbeevaluatedtherearefewwaystodo this,forexamplethroughanalysisofKPI(Key performanceIndicator)orthroughprediction toolsandsignalinterference.Othervery commonandefficientwaytoevaluatethe networkisconductingaDriveTest.Butwhatis it?DriveRouteandsiteDataforthesitestobe drivenistakenfromcustomer.DriveTestLOG FileofthespecifiedDriveRoute\siteissaved andthesamewillbehandovertocustomerat the end of the day [5] DriveTestResourceidentifyroutinefield optimizationissuescableswappingmissing neighbors etc, and rectify the same with the help of the customer. How to companies can decide to improvetheirnetworkcoverageinacertain geographical area? Thesedrivetestingengineersfirstreachtothe towerlocationandmakephysicaloptimization byinspectingissueslikecableswapping, improperhardware,alarms,antennatilting (mechanicalandelectrical),antennaorientation. Afterfieldorphysicaloptimizationhestarts drivetestingbyhisvehicle.Drivetesting engineer collects network data by making a lot of calls(shortandlong).Thedatacollected includesdataforservingcellaswellasthe neighbours.Thisdatacollectedhelpsustofind and analyze the problems in the network.DriveTestperformance measurementsare carriedout forthefollowingreasons: Testthe networkfromthesubscriberspointof view. Testthecompletesystem,endtoend. Benchmarkperformanceagainstcompetitor networks.Testspecificimportantroutesand areas.Testin-buildingcoverageforspecific buildings(Metro,Airport,officeetc.)called walk test. 3. Objective StudyanalyzeshortcalldrivetestforGSM networktoevaluatetheperformanceofQOSof GSM network.4. Implementation Equipment Necessary for Drive test: Tems software Drive test mobile phone (e.g. Ericsson TEMS) External vehicle mounted GPS Laptop with drive test software and GPS connection capability and data cables, multi-connector port etc. Inverter Car TEMSInvestigationisthetoolfor troubleshooting,verification,optimizationand maintenanceofwirelessnetworks.TEMSoffers singleequipmentwithmultiplefunctionslike datacollection,real-timeanalysis,andpost-processing,TEMSInvestigationeliminatesthe needformultipletools,reducingcostsand savingtimeandeffortforoperationsstaff. TEMSinvestigationsupportsallmajor technologies,makingit the ideal testing solution bothforrollingoutnewnetworksandfor ensuringseamlessintegrationwithexisting networks.UsingTEMSInvestigation,operators can increase accessibility, improve retain ability, andachievebetterserviceperformance.TEMS InvestigationsupportforLTE(FDDandTDD), GSM, GPRS, EDGE, WCDMA, HSPA, HSPA+, TD-SCDMA,CDMA(IS-95TOEV-DORevB) andWiMAX,togetherwithsupportforawide rangeofservices.Thetoolensuresseamless integrationamongLTE,WCDMA/HSPA,and GSM/GPRS/EDGEnetworksaswellasLTE, CDMA EV-DO, CDMA200 and IS95 Networks. International Journal of Engineering, Applied and Management Sciences Paradigms, Vol. 22, Issue 01 Publishing Month: March 2015 An Indexed and Referred Journal ISSN (Online): 2320-6608 www.ijeam.com IJEAM www.ijeam.com 119 Figuer (1) Drive Test System Figure (2): Drive Test Tools International Journal of Engineering, Applied and Management Sciences Paradigms, Vol. 22, Issue 01 Publishing Month: March 2015 An Indexed and Referred Journal ISSN (Online): 2320-6608 www.ijeam.com IJEAM www.ijeam.com 120 5. Results Table 1GSM Radio Parameters Table 2 Rx lev:Measured signalstrength (-10 >-115)Rx Qual:Voicequality (0 > 7) depend onBER(bit error rate) Ranges (Legend): International Journal of Engineering, Applied and Management Sciences Paradigms, Vol. 22, Issue 01 Publishing Month: March 2015 An Indexed and Referred Journal ISSN (Online): 2320-6608 www.ijeam.com IJEAM www.ijeam.com 121 Table 3 FER(FrameErasureRate):PercentageofframesbeingdroppedBERactual:(Numberofbit errors / Number of bit transmitted) SQI: Speech Quality Index Ranges (Legend): MS Power control level: Power control (0 > 8) depend on network design.DTX: Discontinuous Transmission. TA:Timingadvance(0>63)EnableMStoadvanceitstransmissiontocompensatethe propagation delay 0: 500m 1: 1 K, and so on. Table 4 GSM Hopping Channels International Journal of Engineering, Applied and Management Sciences Paradigms, Vol. 22, Issue 01 Publishing Month: March 2015 An Indexed and Referred Journal ISSN (Online): 2320-6608 www.ijeam.com IJEAM www.ijeam.com 122 ARFCN:Trafficcarriers.RxLev:measuredsignalstrengthofeachcarrier.C/I:Carrierto Interference rationInterference: Co-Channel or Adjacent interference Ranges (Legend): Table 5: Interference Interference >>>> bad C/I >>>> Bad Rx qual>>>> Bad SQI 6. Results of Simulation Figure (3): Short Call scter a International Journal of Engineering, Applied and Management Sciences Paradigms, Vol. 22, Issue 01 Publishing Month: March 2015 An Indexed and Referred Journal ISSN (Online): 2320-6608 www.ijeam.com IJEAM www.ijeam.com 123 Figure (4): Short call Scter c 7. Conclusion ThestudyanalyzeandsimulationForshort calldrivetestintwosectorsofonesiteof GSM Net work have been doneusing teems softwareprogramthatintroducelogfileto achieve the QOS of GSM networks . References [1]HalonenT.,RomeroJ.,MeleroJ.:GSM, GPRSandEDGEPerformance.JohnWiley & Sons Ltd, 2003 [2]PapersofInternationalJournalof EngineeringandAdvancedTechnology (IJEAT) [3]K.SandeepRajeevetalInt.Journalof Engineering Research and Applications [4]WorkofB.VenkataSaiSireesha,Dr.S. Varadarajan [5]Work of Ahmed Omar Abd albadea