资源描述：
《美赛论文模板》由会员上传分享，免费在线阅读，更多相关内容在工程资料-天天文库。
1、TeamControlNumberForofficeuseonlyT1T2—T3T40000ProblemChosenAForofficeuseonlyFlF2—F3—F4—2014MathematicalContestinModeling(MCM)SummarySheet(Attachacopyofthispagetoeachcopyofyoursolutionpaper.)RepeatersCoordinationAndDistributionFebruary6,2015AbstractInthispaper,itaimstocomputingprob
2、lemonRelayStrategy(repeaterscoordinationanddistribution).Accordingtoadvancedradiocellularcoveragetechnology,usageoffrequencyattenuationandgeometricmappingmethods,Hatamodel.cellularcoveragesolutionandFDM(FrequencyDivisionMultiplexing)modelwereestablished.ThealgorithmsusedMATLABtosi
3、mulate,withthefinalmodelingresultsofsensitivityanalysisandimprovement&promotiononmodels.Questionone:Foracircularflatareaofradius40milesradius,determinetheminimumnumberofrepeatersnecessarytoaccommodateL000simultaneoususers.Assumethatthespectrumavailableis145to148MHz,thetransmitterf
4、requencyinarepeateriseither600kHzaboveor600kHzbelowthereceiverfrequency,andthereare54differentPLtonesavailable.Answer:BasedonFrequencyattenuationexpressionandcalculationwithMATLAB,itfiguredouttheeligiblecoverageradiuses,whichare30kmforBS(basestation),and14.9kmforrepeater.Assumingt
5、heusersinagivenareaunderuniformdistribution,usingadvancedcellularcoveragesolution,wecancalculatethatminimumnumberofrequiredrepeateris36undercellularfeatures.BasedontheUSVHFspectrumallocationstandard,theminimumspacingforadjacentchannelsis30kHz.Andwithupto54differentPLtones,maximum4
6、320channelscanbeallocatedtoprovide1000simultaneoususerstouseatthesametime.Conclusion:Theminimumnumberofrepeatersnecessarytoaccommodate1,000simultaneonsusersis36.QuestionTwo:Howdoesyoursolutionchangeifthereare10,000users?Answer:Sincethegivenspectrumisinafixedrange,evenif54different
7、PLtonescannotbeallocatedenoughchannelsfor10,000simultaneoususers.Sothenumberofrepeaterswillbeincreased,meanwhile,thegivenareawillbedividedintodifferentparts.Ontheassumptionthatuniformdistributionofthepopulationinthegivenarea,itwillbedividedinto3sub-regionsequallybyanalyzingthebind
8、ingdomain,frequencyspectrumandPLt
