Abstract:〗In the traditional precise point positioning(PPP),the integer ambiguity can only be estimated as float value,which restricts the further enhance of PPP accuracy for the existence of fractional cycle biases(FCB)in the carrier phase observations from the receiver and satellite ends.In the study,the ionospherefree ambiguity is decomposed into widelane(WL)and narrowlane(NL)ambiguities.The betweensatellitedifference(BSD)operation can remove the FCB included in WL and NL ambiguities at the receiver end.The satellitebased FCB contained in the WL ambiguity provided by the international GNSS service(IGS)analysis center CNES can be used to recover the integer nature of the WL ambiguity.Due to the precise satellite clock corrections provided by CNES assimilate the satellitebased FCB of the NL ambiguity,the integer nature of NL ambiguity can also be recovered after applying the precise clock corrections.The analysis results based on the IGS observation data indicate that the positioning accuracy of BSD PPP fixed resolution is significantly better than the zerodifference(ZD)PPP float resolution.The improvement rate of 3dimensional positioning accuracy reaches 63.8%.
Pan Lin,Cai Changsheng,Zhu Jianjun. THE METHODS AND RESULTS OF PRECISE POINT POSITIONING
WITH BETWEENSATELLITEDIFFERENCE INTEGER AMBIGUITY FIXING[J]. jgg, 2014, 34(5): 90-93.