Antenna Phase Center Offset and Attitude Control during Eclipse for GPS Block III Satellites

Abstract

While the precise ephemeris used for precise positioning by the satellite navigation system is generally referencing navigation satellite's center of mass, fundamentally satellite's antenna phase center should be used and they have difference up to a few meters. The antenna phase center offsets of GPS Block III satellites are investigated and reported. The variation of yaw attitude of GPS Block III satellite is also investigated, which is necessary to apply the antenna phase center offset and useful for the correction of phase wind-up effects due to relative rotation of transmitting and receiving antennas. It is shown that the yaw angle of Block III satellite is controlled in the way different from older satellites during eclipse periods when satellite attitude variates largely.