ADJUSTING THE DATA OF A TWO-ANTENNA GNSS SYSTEM TO THE IMU-FIXED COORDINATE FRAME

摘要

A two-antenna GNSS/INS system is considered. The equations have been derived to calculate the heading of the IMU frame using the data from the two-antenna system with proper account for the misalignment of the antenna baseline with respect to the IMU axes. Formulas for the error of this calculated heading and the error variance are given. A procedure proposed for calibration of antenna baseline angular deviations does not need any external measurement equipment. It relies on the pitch and roll generated by the IMU, aided with the data from one GNSS antenna and the antenna baseline geographical components derived from the differences in phase measurements from two antennas. The test results are presented.