摘要：Two methods for smoothing pseudorange observable by Carrier and Doppler are discussed. Then the procedure based on the RINEX observation files is tested using the Ashtech Z-XII3T geodetic receivers driven by a stable external frequency at UNSO. This paper proposes to adapt this procedure for the links between geodetic receivers, in order to take advantage of theP codes available onL1 andL2. This new procedure uses the 30-second RINEX observations files, the standard of the International GPS Service (IGS), and processes the ionosphere-free combination of the codesP1 andP2; the satellite positions are deduced from the IGS rapid orbits, available after two days.
关键词：GPS; time and frequency transfer; geodesy; smoothing
