DGPS Kinematic Carrier Phase Signal Simulation Analysis for Precise Aircraft Velocity Determination

A Northern Telecom STR2760 phase coherent differential GPS simulator is used to analyse the velocity accuracy achievable under aircraft dynamics using selected receiver technologies. The results of two C/A code L1 receiver types are presented herein, namely an Ashtech G-12 TM , and a NovAtel PowerPack OEM2 equipped with special Precise Velocity (PV) firmware which improves the receiver generated Doppler measurements. Simulated aircraft trajectories with velocities up to 120 m/s, accelerations up to 50 m/s 2 , and jerks up to 25 m/s 3 , are used. The code and carrier phase observables are processed in single difference mode with the velocity estimates based solely on the Doppler observables. The accuracy of receiver generated Doppler-derived velocities and that of integrated carrier phase-derived velocities are tested as a function of aircraft dynamics.