简介:CombinedGPS/GLONASScanincreasetheaccuracyandreliabilityofpositioningespeciallyinsomeapplicationswithmanyimpediments.Duetotheatmospheredelay,thecommonlyusedmethodsforprocessingshortdistancebaselinescannotbeimplementedinlongdistancebaselines.Inthispaper,anewdataprocessingstrategyforlongdistancebaselinesisproposed,whichusesthepropertiesofsomecombinationobservablesofcombinedGPS/GLONASSanddistancebaselinesmaycometotheorderof10-8andcombinedGPS/GLONASSimprovestheaccuracyoverthatofGPS-onlypositioning,whichbringsbenefittocrustdeformationmonitoringandresearchongeodynamics.
简介:DuetothedifferentsignalfrequenciesfortheGLONASSsatellites,thecommonly-useddouble-differencingprocedureforcarrierphasedataprocessingcannotbeimplementedinitsstraightforwardform,asinthecaseofGPS.Inthispaperanoveldataprocessingstrategy,involvingathree-stepprocedure,forintegratedGPS/GLONASSpositioningisproposed.Thefirstispseudo-range-basedpositioning,thatusesdouble-differenced(DD)GPSpseudo-rangeandsingle-differenced(SD)GLONASSpseudo-rangemeasurementstoderivetheinitialpositionandreceiverclockbias.ThesecondisformingDDmeasurements(expressedincycles)inordertoestimatetheambiguities,byusingthereceiverclockbiasestimatedintheabovestep.ThethirdistoformDDmeasurements(expressedinmetricunits)withtheunknownSDintegerambiguityfortheGLONASSreferencesatelliteastheonlyparameter(whichisconstantbeforeacycleslipoccursforthissatellite).Areal-timestochasticmodelestimatedbyresidualseriesoverpreviousepochsisproposedforintegratedGPS/GLONASScarrierphaseandpseudo-rangedataprocessing.Otherassociatedissues,suchascycleslipdetection,validationcriteriaandadaptiveprocedure(s)forambiguityresolution,isalsodiscussed.Theperformanceofthisdataprocessingstrategywillbedemonstratedthroughcasestudyexamplesofrapidstaticpositioningandkinematicpositioning.Fromfourexperimentscarriedouttodate,theresultsindicatethatrapidstaticpositioningrequires1minuteofsinglefrequencyGPS/GLONASSdatafor100%positioningsuccessrate.Thesingleepochpositioningsolutionforkinematicpositioningcanachieve94.6%successrateovershortbaselines(<6km).
简介:一、概述实时动态RTK定位技术是GPS测量技术与数据处理技术、数据传输技术相结合的产物,是GPS测量技术发展中的一个新的突破。在RTK测量技术出现之前,GPS相对定位的作业模式有静态定位作业模式、快速静态定位模式、准动态定位模式和动态定位模式,其测点坐标需通过测后处理,即必须将观测数据传输到计算机解算才能获得。无法实时获取定位结果,而且也无法对观测数据的质量进行实时检核,因而出现在数据后处理中发现观测成果不合格进行重测的情况。对此采取的措施主要是延长观测时间,获取冗余观测数据,以保障测量结果的可靠件,由此降低了GPS测量的工作效率。
简介:一、引言自从GPS技术应用于测量工作以来,因其精度高、全天候、成本低和效率高等特点被广泛应用于测绘及其它领域。它作为野外定位的最佳工具已成为建立平面控制网的主要测量技术手段,应用的范围越来越广泛。尤其在野外地质勘查找矿方面的一些应用越来越受到野外一线技术人员的重视和青睐。GPS技术能适应地质勘查中矿区预查、普查阶段各类勘查工程放样、定测的技术要求;同时也节省了人力、物力、财力,提高了测量工作在矿区预查、普查阶段的工作效率。下面简单介绍在国土资源大调查及矿区普查中利用GPS技术进行控制测量、剖面测量以及地质点和钻孔放样定测的应用情况。