The carrier phase measurement method is used in the satellite compass, which is to measure the instantaneous phase received by the antenna at both ends of the baseline, and compare the phase difference. Two GPS receivers receive the radio wave information of the same satellite respectively, take out the pseudo range and phase parameters from them, and calculate the distance between the satellite and two GPS antennas by GPS compass. Then take out the position parameters of the satellite from the radio wave, so as to calculate the position from the satellite to the geocentric coordinate system. It is better to get the coordinates of the satellite in the horizontal coordinate system with the reference antenna as the origin through coordinate transformation. Instead of setting the position of the nonreference antenna as the position parameter, the distance difference between the satellite and the two antennas can be calculated according to the distance formula between the two points, and the calculated distance can be calculated The difference is compared with the distance difference from the previous observation, and the difference can be minimized by changing the unknown parameter value of the antenna position. Thus, the unknown parameter of the nonreference antenna position can be solved, and the azimuth of the baseline connecting the two antennas in the horizontal coordinate system can be obtained, that is, the bow azimuth of the satellite compass.