基于DSP+FPGA的超紧组合导航系统研究

Research and Realization of GNSS/SINS Ultra-Tightly Coupled Integrated Navigation System Based on DSP + FPGA

载体在飞行过程中遇到高动态、障碍遮挡等情况时,GNSS接收机由于环路失锁或者收星数小于4颗无法正常工作。为改善组合导航系统性能,设计了一种基于DSP+FPGA的GNSS/SINS超紧组合导航系统,在利用惯性信息辅助GNSS跟踪环路的同时,引入外部高度信息,采用全维滤波方式进行信息融合。实验结果表明:该系统改善了接收机的动态性能,可在加速度为60g、加加速度为20g/s的高动态仿真环境下正常工作;在收星数少于4颗时,引入的外部高度信息可改善少星情况下的导航精度。

When aircraft run under the situation such as high dynamic flying, receiver signal being blocked and so on, the GNSS receiver can not work normally due to losing lock or getting less than four satellites. In order to improve the performance of integrated navigation system, GNSS/SINS ultra-tightly coupled integrated navigation system based on DSP ＋ FPGA is designed in this paper. It not only use inertial information aided for the tracking loop with the predicted frequency, but also adopt full dimension filtering to achieve information fusion by introducing external height information. The experimental results show that the method can meet the dynamic requirement of 60g acceleration regarding the satellite. When the satellites number is getting less than four, the navigation precision can be imporoved by the external height information introduced.