The Attitude Measurement Technique Based On GPS

In the field of Guidance, Navigation and Control Technologies, the attitude determination based on GPS has the advantage of real-time efficiency and stable accuracy. At present, the method of attitude determination using carrier phase has created a new part for GPS navigation. Real-time attitude determination is derived from extremely precise differential carrier phase measurements among multiple GPS antennas mounted on the vehicle. This thesis investigates the attitude determination using carrier phase differencing technique with an emphasis on theoretical aspects and algorithms. The implementation of a determination system is also discussed.The attitude determination technique suggested in the thesis consists of three vital stages, which contain data acquisition and processing, ambiguity resolution and attitude calculation. In the stage of data acquisition, the necessary information for attitude determination is extracted from GPS receivers in binary format, including dual-differential carrier phase and ephemeris of GPS satellites. In the stage of ambiguity resolution, QR decomposition algorithm builds the smaller search space and the restrictions, such as length of baseline, integrity of ambiguity and RATIO inspection, examines the solution of search space and reaches to the real solution.Based on the theoretical study, the attitude determination technique is using two SUPERSTAR II OEM receivers for hardware. The system software is based on Visual C++ 6.0 dialogue mode and CserialPort class, and applys the Matcom to accomplish programming mixed VC with MATLAB. Finally, a lot of field tests are employed and the results proved the good feasibility of the system.