Orbit Determination using Radio Interferometer of Small-Diameter Antennas for LEO Satellites

The method of orbit determination using radio interferometer of small-diameter antennas for low-Earth-orbit (LEO) satellites is proposed. In this method, cross correlation phases are measured between received signals by two antennas. From numerical simulations and real observations analyses using a new software we have developed, orbit determination filter (ODEF), it is confirmed that the satellite position and velocity can be estimated with an accuracy of a few tens of meters and a few tens of mm/s for baseline length of 75 m and the altitude of the satellite of 1400 km. In addition, a numerical simulation makes clear that the position error becomes smaller as the baseline length gets longer.