Research On GPS-based Three Dimensional Attitude Determination Technology

Multi-Antenna attitude determination system using GPS/GNSS is gradually replacing traditional methods due to its high precision, free accumulated error, no-misalignment, and low-cost. Attitude determination using GPS is a new area of applications of GPS, and more and more be applied in aero and navigation. Two or three dimensional attitudes of the vehicles can be achieved in real-time mode by processing differential carrier-wave phase measurement from different GPS antennas.Based on the research of theory of attitude determination using GPS, technology of differential carrier-wave, algorithm of ambiguity resolution, and the research on universal ambiguity resolution is highlighted, a new optimal AFM (ambiguity function method) was applied, and complete attitude determination software was accomplished. Theoretical analysis and experiments unanimously indicates that this novel algorithm requires less calculation and boasts higher reliability than those traditional ones. Empirical data are collected through abundant experiments conducted on an attitude determination platform composed by three Superstar II OEM boards. The experimental results show that, an accuracy of about 0.1°(1σ) for yaw, 0.3°(1σ) pitch and roll was achieved, and can fulfill system's strict requirements on real-time response. The reasons behind some problems and errors are suggested through careful investigations and potential solutions are proposed to further enhance the attitude determination system.