Improved integrated navigation method of micro position and orientation system based on installation error angle calibration

Micro position and orientation systems (POSs) are motion compensation equipment for airborne remote sensing systems, and are composed of an inertial navigation system (INS) and a global navigation satellite system (GNSS) with double antennas. INS/GNSS integrated navigation is a key technology to measure micro POS motion information. However, the installation error angle between the INS and dual antennas seriously reduces the navigation accuracy. To solve this problem, an improved integrated navigation method of micro POS based on installation error angle calibration is proposed. First, a calibration method for the installation error angle based on a high-precision POS and the dual antennas is presented. Then, an improved real-time navigation algorithm based on error angle compensation is established. Finally, the flight experiment results indicate that the proposed method can effectively improve the navigation accuracy compared to the uncalibrated method, especially the attitude and velocity accuracies, which are improved by 36% and 27%, respectively.