Satellite orbit determination using GPS carrier phase in pure kinematic mode

The mainstream approach to satellite orbit determination has been a dynamic one. This approach is fine as long as the satellite dynamic model is accurate. When the dynamics model is not accurate, the reduced dynamic approach is better suited for orbit determination. Even a purely kinematic solution can be obtained by using the reduced dynamic approach. However, this method is computationally very extensive and still requires a reasonably good satellite dynamics model to compute its reference orbit.;A new algorithm and computer program, KODAC (Kinematic Orbit Determination And Comparison), was developed for satellite orbit determination using a kinematic approach with the GPS carrier phase as observable. Since the GPS signal has enough spatial geometric information, it is possible to determine the satellite orbit using a purely kinematic approach. In this method both double and triple differenced GPS carrier phases are used as observables, and epoch by epoch satellite positions and DD ambiguities are estimated by assuming GPS ephemerides and ground station positions are known. TOPEX GPS data is used for this study, and the final radial rms orbit accuracy of 5 cm with respect to the MSODP (Multi Satellite Orbit Determination Program) dynamic solution is achieved. This new kinematic approach has the advantage of having consistent orbit accuracy regardless of satellite altitude. The same algorithm can be applied to any satellite with a GPS receiver due to the algorithm's non-dynamic approach. The TOPEX on-board receiver has only six channels, and its signal view angle is limited. With an improved on-board receiver equipped with more channels and a wider GPS view angle, an improvement in orbit accuracy can be expected for future satellite missions.