《数字测图》课件-1.3GNSS RTK认识

数字测图DigitalMappingGNSSRTKUnderstandingGNSSRTK认识是集计算机技术、数字通讯技术、无线电技术和GPS测量定位技术为一体的一种运用载波相位差分技术进行实时定位的GPS测量系统。Itisanintegratedsystemthatcombinescomputertechnology,digitalcommunicationtechnology,radiotechnology,andGPSmeasurementandpositioningtechnology.ItisaGPSmeasurementsystemthatusescarrierphasedifferentialtechnologyforreal-timepositioning.GNSSRTK测量系统GNSSRTKMeasurementSystemGNSSRTK测量系统GNSSRTKMeasurementSystem0102GPSreceiverGPS

接收设备数据传输设备Atatransmissiondevice03Software软件系统数据传输系统由基准站的发射电台与流动站的接收电台组成，它是实现实时动态测量的关键设备。AtaTransmissionDevice数据传输设备Thedatatransmissionsystemconsistsofatransmittingstation'sradiostationandamobilestation'sreceivingstation,itisakeydeviceforachievingreal-timedynamicmeasurement.AdvantagesofRTKMeasurementTechnologyRTK测量技术的优点除具有GPS测量的优点外，同时具有观测时间短，能实现坐标实时解算的优点，因此可以提高生产效率。HastheadvantagesofGPSmeasurementinadditiontoshortobservationtimeandtheabilitytoachievereal-timecoordinatesolution,whichcanimproveproductionefficiency.实时动态定位如采用快速静态测量模式，在15

km范围内，其定位精度可达1～2

cm，可用于城市的控制测量。Real-timedynamicpositioning,suchasusingarapidstaticmeasurementmode,canachieveapositioningaccuracyof1-2cmwithinarangeof15kmandcanbeusedforurbancontrolmeasurement.GNSSRTK的基本原理GNSSRTKBasicPrinciplesGPS静态测量的方法是各个接收机独立观测，然后用后处理软件进行差分解算。Eachreceivertoindependentlyobserveandthenusepost-processingsoftwaretoperformdifferentialcalculations.

两台接收机（一台基准站，一台流动站）都在观测卫星数据，同时，基准站通过其发射电台把所接收的载波相位信号（或载波相位差分改正信号）发射出去；那么，流动站在接收卫星信号的同时也通过其接收电台接收基准站的电台信号；在这两个信号的基础上，流动站上的固化软件就可以实现差分计算，从而精确地定出基准站与流动站的空间相对位置关系。GNSSRTK的基本原理GNSSRTKBasicPrinciplesBothreceivers(onereferencestationandonemobilestation)areobservingsatellitedata,andatthesametime,thereferencestationtransmitsthereceivedcarrierphasesignal(orcarrierphasedifferentialcorrectionsignal)throughitstransmittingstation;So,mobilestationsnotonlyreceivesatellitesignalsbutalsoreceiveradiosignalsfromreferencestationsthroughtheirreceivingstations;Onthebasisofthesetwosignals,thesolidificationsoftwareonthemobilestationcanachievedifferentialcalculation,therebyaccuratelydeterminingthespatialrelativepositionrelationshipbetweenthereferencestationandthemobilestation.GNSSRTK的基本原理GNSSRTKBasicPrinciples在这一过程中，由于观测条件、信号源等的影响会有误差，即为仪器标定误差，一般为平面1cm+1ppm，高程2cm+1ppm。Inthisprocess,theremaybeerrorsduetotheinfluenceofobservationconditions,signalsources,etc.,whichareinstrumentcalibrationerrors,generally1cm+1ppmintheplaneand2cm+1ppmintheelevation.近几年来，一些大城市开始建立网络RTKGPS系统，这种系统被称为连续运行参考站（ContinuouslyOperatingReferenceStations，CORS）。Inrecentyears,somelargecitieshavebeguntoestablishnetworkRTKGPSsystems,whicharecalledcontinuouslyoperatingreferencestations(ContinuouslyOperatingReferenceStations,CORS).连续运行参考站CORS系统ContinuouslyOperatingReferenceStationsCORSSystem连续运行参考站CORS系统ContinuouslyOperatingReferenceStationsCORSSystem一个或若干个连续运行的基准站Oneormorecontinuouslyoperatingbasestations数据处理中心Dataprocessingcenters数据发布中心Datapublishingcenters用户流动站UsermobilestationsSinglebasestation单基站多基站网络CORSMulti-basestationnetworkCORS连续运行参考站CORS系统ContinuouslyOperatingReferenceStationsCORSSystem连续运行参考站CORS系统ContinuouslyOperatingReferenceStationsCORSSystemCORS采用虚拟参考站法，是在一个市区（较大的区域）均匀地布设多个连续运行的参考站，根据各参考站长期跟踪的观测结果，反演出区域内GPS定位的一些主要误差模型，如电离层、对流层、卫星轨道等误差模型。CORSusesthevirtualreferencestationmethod,itistouniformlydeploymultiplecontinuouslyoperatingreferencestationsinacity(largerarea)basedonlong-termtrackingobservationsofeachreferencestation.ThemainerrormodelsofGPSpositioninginthearea,suchasionosphere,troposphere,satelliteorbit,etc.,canbeinferredfromtheobservationresultsofeachreferencestation.★基本工作原理Basicworkingprinciple连续运行参考站CORS系统ContinuouslyOperatingReferenceStationsCORSSystem系统运行时，将这些误差从参考站的观测值中减去，形成所谓的“无误差”观测值，再利用无误差观测值与用户流动站观测值的有效组合，在流动站附近（几米到几十米）建立起一个虚拟参考站。将流动站和虚拟参考站进行载波相位差分改正，就实现了RTK定位。Whenthesystemisrunning,theseerrorsaresubtractedfromtheobservationvaluesofthereferencestations,formingso-called"zero-error"observationvalues.Then,byeffectivelycombiningthezero-errorobservationvalueswiththeobservationvaluesoftheusermobilestationsnearthemobilestations(severalmeterstoseveraltensofmeters),avirtualreferencestationisestablished.Byperformingcarrierphasedifferentialcorrectiononthemobilestationandthevirtualreferencestation,RTKpositioningisachieved.★基本工作原理BasicworkingprincipleGNSSRTK直接反映的是WGS-84坐标，所以要通过坐标转换把GPS的观测成果变成我们需要的目标坐标系统下的坐标。更多的RTK原理一般在控制测量课程进行介绍，数字测图更多的则是应用。GNSSRTKdirectlyreflectstheWGS-84coordinatesystem,soweneedtousecoordinateconversiontoconverttheGPSobservationresultsintothecoordinatesofthecoordinatesystemweneed.MoreRTKprinciplesaregenerallyintroducedincontrolmeasurementcourses,whiledigitalmappingfocusesmoreonapplication.连续运行参考站CORS系统ContinuouslyOperatingReferenceStationsCORSSystem安置基准站特别注意远离电磁波发射源、远离有遮挡的建筑物。基准站安置好后安置移动站，包括连接碳纤对中杆，移动站主机和接收天线，完毕后主机开机；安装手簿托架，固定数据采集手簿，打开手簿，进行蓝牙连接，连接完毕后即可进行仪器设置操作。Whenplacingthebasestation,itisparticularlyimportanttokeepitawayfromelectromagneticwaveemittersandbuildingswithobstruction.Afterthebasestationisinstalled,themobilestationisi