Design of missile-borne GNSS/SINS tightly-coupled integrated navigation system

Aiming at the characteristics of large volume, low degree of integration in traditional missile-borne distributed tightly-coupled navigation system, a compact integrated navigation system is designed. Low cost IMU(inertial measurement unit) and GNSS receiver are used as navigation sensors, and the algorithm is programmed on a navigation computer designed based on DSP C6747+FPGA shallow-parallel architecture, the size of the whole system is only 13cm∗14cm∗12cm without external antenna. In terms of algorithms, an adaptive Kalman filter algorithm is adopted for information fusion. Meanwhile the status of GNSS is judged by a new proposed algorithm before Kalman filter to avoid the affect of abnormal values of pseudo-range and pseudo-range rate. In addition, satellite-selection algorithm is designed and used step by step to avoid the influence of long time cost of satellite-selection algorithm. Finally, the results of vehicle experiments show that the designed system has very high navigation precision, the dynamic level positioning error is less than 2m(1σ) and velocity error is less than 0.2m/s(1σ).