A 16-parameter GEO Broadcast Ephemeris

Currently, the broadcast ephemerides used in GEOs are same as those of the MEOs and IGSOs in the BeiDou navigation constellation. However, a trade-off strategy, i.e. an orbital inclination of 5° rotation, is needed in the fitting algorithm to solve the ephemeris parameters as well as the user satellite position computation for GEOs. Based on the standard broadcast ephemerides, the representations of both the orbit and its perturbation were revised according to the second class of nonsingular orbital elements. In this research, a 16-parameter broadcast ephemeris is presented specifically for GEOs,and user satellite position computation formulas were derived correspondingly. Fit simulations show that the root of mean squares (RMS) of user range error (URE) with two hour and three hour data sets are better than 0.05m and 0.1m, respectively.