GPS英文介绍

SummarizingTheGlobalPositioningSystemAbstract:GlobalPositioningSystemisbasedonthebackgroundoftheUnitedStatesDepartmentofDefense.Itisdesigned,invested,developed,andoperatedbytheUnitedStatesDepartmentofDefense,GPSisasatellite-basedpositioningandtimetransferingGPSpositioningfunctionhasawiderangeofapplicationsinthemodernmeasurementandamoremodernbuilding.GPS-RTKtechnologyisalsowidelyusedinmodernizationbuilding,andnowGPShasalsobeenshowntobeanimportantciviliancommunitiesofinterest,andincreasinglywiderangeofapplicated.Keyword:GPS,Locating，RTK，Layout，Survey1.BackgroundThe50s,theformerU.S.S.Rhasnotlaunchedhumanitiesfirstartificialearthsatellite,theAmericanscientistsinalongitstrackresearchin,haddiscoveredtheDopplershiftphenomenon,andhasfacilitatedDopplersatellitenavigationposi-tioningsystemcompletingusingthisprinciple,hasobtainedtheenormoussuccessinthemilitaryandtheciviaspect,wasinanavigationlocalizationhistoryleap,ourcountryoncehasalsointroducedmanyDopplerreceiver,appliedtotheislandassociationmeasured,theEarthexploredandsoontheappliedtotheislandassociationmeasured,theEarthexploredandsoonthedomain.ButbecauseDopplersatelliteorbithighlylow,signal-carrierfrequencylow,thetrackprecisionenhanceswithdifficulty,causesthepointingaccuracylowly,satisfiesthegeodeticsurveyortheprojectsurveyrequest,ismoreimpossibletouseintheastronomyEarthdynamicsresearch.Inordertoenhancethesatellitepositioningtheprecision,USstartedfrom1973toprepareforconstructionglobalpositioningsystemGPS(GlobalPositioningSystem).Afterhasenteredtheplanproof,thesystemteststage,startedin1989tolaunchtheofficialworksatellite,andcompletelycompletedin1994,investmentuse.TheGPSsystemspaceartiallyiscomposedbytwentyonesatellites,evenlydistributesinsixorbit,thegroundlevelis20,000Kilometers,theinclinationoforbitis55,theflatheartrateapproximatelyis0,theweekcontractis12hours,thesatellitetotheearthlaunchingtwowavebandsintelligencesignals,theintelligencesignalfrequencyrespectivelyis1575.442megacyclespersecond(theL2waveband),onthesatellitehasinstalledtheprecisionveryhighatomicclock,guaranteesthefrequencythestability,modulatesinthecarrierhastheexpressionsatellitepositionthebroadcaststarexperience,useintherangefinderC/AcodeandPyard,aswelladothersysteminformation,canintheglobalscope,towillfullymulti-userprovidethehighaccuracy,all-weather,iscontinual,real-timethreedimensionalmeasuresfast,thethreedimensionallocalizationandthetimeservice.TheGPSsystemcontrolsectionbyislocatedintheAmericanfoundationsofthestates5monitoringstationstobecomposed,thesestanddidnotaskbreaksCarriesontheobservationtoGPSsatellite,andwillcalculateandtheforecastinformationbytheinfusionstandsrenewstothesatelliteinformation.TheGPSsystemuserisextremelycovert,itisonekindofone-waysystem,theuseronlyreceivesbutdoesnotneedthetransmittingmessage,andthereforeuser'squantityalsoisnotlimited.AlthoughGPSistheunificationstartsis,butveryquantityalsoisnotlimited.AlthoughGPSreceiverandprocessingsoftwareemergeinabundance.AtpresentthereceiverwhichappearsintheChinesemarketmainlyhasROGUE,ASHTECH,TRIMBLE,LEICA,SOKKIA,TOPCONandsoon..Cancarryontheobservationtotwofrequenciesthereceivertobecalledthedoublefrequencyreceiver,onlycancarryontheobservationtoafrequencythereceivertobecometheinference.Saysregardingthemappinguser,GPShascausedtherevolutionarychangeinthemappingdomain,atpresent,inthescopeseveralthousandkilometerscontrolsnetwork,intheprecisionfromhundredtothemillimeterlevellocalization,generallyallGPStookthefirstchoicemethod,isdaybydaymaturealongwiththeRTKtechnology,GPSstartedtodecimeterandevenacentimeterlevellayout,domainseepageandsoonhighaccuracydynamiclocalization.TheinternationalGPSgeodeticsurveyservedIGSwithEarthdynamicsfrom1992,hasestablishedmanydatastorageandtheprocessingcenterinthewholeworld,yeartoyearobservedastationwithhundred,ourcountryhasalsosetupShanghaiYuShan,Wuhan,Xian,Taiwanandsoonmanyyeartoyearmeasuringplatformsstation,thesestationsobservationdatapassedoneverydaythroughtheinternetnettoUS'Sdatastoragecenter,IGSalsonearlyreal-timesynthesizesvariousdataprocessingcentertheresult,andtheparticipantinternationalearthrotationservedtheIERSglobalcoordinatesreferencesystemmaintenanceandtheearthrotationparameterissue.Theuseralsomayfreeon-lineobtainproductandsoonobservationdataandprecisestarexperiencefrominternet.TheGPSsystemreal-timenavigationpointingisveryhigh,UShasimplementedtheso-calledSApolicyin1992,namelyreducesthebroadcaststartoundergothestarpositionprecision,reducesthestarclocktochangethepositivenumbertheprecision,addsonthehighfrequencyvibrationtothesatellitedatumfrequency(tocausefalsedistancemeasuringaccuracytoreducewithphase),latterhasimplementedtheA-Spolicy,soonPyardchangeisYyardnamelyfurtherlimitstotheprecisefalsedistancesurvey,butAmericanmilitaryandspecialpermissionusernotthesepolicesinfluences,butUSinordertoobtainthebiggercommercialinterest,thesepolicyendsarecancelled.2.GPSlocalizationprincipalTheGPSreceivermayreceiveanduseinthetimeserviceaccuratelytothenanosecondleveltimeinformation;willuseintoforecastthefutureforseveralmo