Quality Control for GPS-Based Attitude Determination Systems: Analysis and Simulations

For high accuracy real-time GPS-based attitude determination, the carrier phase ambiguities must be resolved as quickly as possible. The use of GPS for determining attitude through the differencing of carrier phase measurements from multiple antennas, which may be aided by INS or a gyro sensor, has been investigated by many researchers. So far investigations have mainly focused upon improving the time-to-ambiguity resolution and in improving the accuracy of the derived yaw, pitch and roll parameters. However, of equal importance are the issues relating to the quality control of the attitude solution, such as the reliability of the solution and the detection of errors. This may be influenced by such factors as the different antenna configurations, the type of GPS receiver used, the addition of navigation sensors for augmentation, and the data processing techniques used to determine the attitude parameters. This paper will investigate the effects of several factors that influence the precision, and reliability, of the estimated attitude parameters. A number of simulation studies will be described, that demonstrate what is theoretically expected of such attitude determination systems. These results will be compared with a series of experiments set-up to verify the outcomes of the simulations