Research On Single Point Positioning Algorithm Based On GPS And BDS

This paper mainly explores the correction method of GNSS single point positioning error model,the cycle slip detection and repair of carrier phase observation value and the estimation method of location parameter.On this basis,the theory and algorithm of single point positioning of GPS/BDS single system and its combination system are studied.The data processing software is compiled.The theory and algorithm are verified by the actual data.The main research contents are:(1)Due to the transformation of small areas of the geocentric coordinate system and reference center coordinate system the existence of ill conditioning problems and after the center of gravity of the sick only reduction cannot be eliminated,in order to eliminate the ill posed by generalized cross rule,combined with the biased estimate of coordinate conversion,and thus put forward transformation model of coordinate centralization based on generalized cross rule and biased estimate.(2)The error correction model: the correction of satellite,the correction of signal propagation,and the correction of signal receiving are studied.Besides,this thesis focuses on the signal delay correction and the hardware delay correction,tropospheric error correction model and how the observations are affected by the earth rotation correction.(3)The observed value of cycle slip detection and repair: to analyze the data of cycle slip detection by using different methods containing combined MW combination method,TECR,polynomial quasi legal and Doppler method to make the detection more accurate and effective.(4)Parameter estimation method: locating GPS and BDS single and combined system by least square method,Bancroft direct and extended Kalman filtering method.(5)GPS/BDS combination of single point positioning: exploring the GPS and BDS unification of time datum and Coordinate Datum;resolving of combined pseudo range observation using the least square method and the Extended Kalman Filtering.(6)For the single GPS and BDS system,equal rights and high Angle weighting model was applied to analyze single point positioning with pseudo range;for the combined GPS and BDS system,in addition to the use of these two sets,Helmer's model was added to analyze.