Effect mitigation of satellite clock bias interpolation error on PPP by using time-differenced positioning technique
Aiming at the problem that satellite clock bias interpolation has to be conducted in precision point positioning(PPP)when the sampling interval of global navigation satellite system(GNSS)receiver is smaller than that of the satellite clock bias product,resulting in satellite clock bias interpolation(SCBI)error,which causes the deterioration of PPP accuracy,the paper proposed a method to mitigate SCBI error's effect on PPP accuracy by using time-differenced positioning(TDP)technique:the shortcomings of existing methods to deal with SCBI error,including the conventional method,the high sampling rate satellite clock bias difference method,the downsampling positioning method and the stochastic modeling method,were analyzed;and the PPP was conducted with satellite clock bias interval(not affected by the SCBI error)to obtain the PPP positioning results consistent with the satellite clock bias sampling rate;then,the TDP was used to obtain high sampling rate coordinate difference between epochs;finally,the PPP positioning results with the satellite clock bias interval were combined with the high sampling rate coordinate differences between epochs to obtain the GNSS positioning results in which the SCBI error was reduced.Experimental results showed that when the satellite clock bias interval is 30 s(300 s),the stochastic modeling method would improve the positioning accuracy by about 0.2%(14.1%)compared with the conventional method,while the TDP method would improve the positioning accuracy by about 7.7%(19.1%)compared with the conventional method;in general,the proposed method could be simple and easy to use for effectively mitigating SCBI error's effect on PPP accuracy and improve positioning accuracy for kinematic PPP.
global navigation satellite system(GNSS)precise point positioning(PPP)satellite clock bias interpolation errortime-differenced positioning
NETL
NSTL
万方数据
