基于北斗卫星组合导航精度优化设计研究

Design of Accuracy Optimization Based on COMPASS Integrated Navigation System

研究北斗卫星组合导航系统实时性和定位精度优化问题。针对UPF算法由于计算量大而不满足组合导航系统实时性要求的问题,通过在采样阶段减少状态变量及重构Sigma点和在重采样阶段利用范数"剔除"无效观测量等手段对UPF算法进行改进,并应用于北斗/INS组合导航系统中。为了验证改进算法的有效性,将改进UPF算法和传统UPF算法进行对比,并通过相对时间、状态估计误差和均方差对实验结果进行定量分析。实验结果表明,改进算法能够有效地缩短组合导航系统的解算时间,提高定位精度,并且稳定性较高,达到了预期的要求。

The improvement of the real-time and the positioning accuracy for the COMPASS/INS integrated navigation system is studied. Aiming at to solve the problem that the UPF algorithm cannot satisfy the application demand of the real-time in the COMPASS/INS integrated navigation system, the paper proposes an improved UPF algorithm which will be improved by reducing the state variables and reconstructing Sigma points in the importance sampling stage and ＂eliminate＂ the use of abnormal observations based on the norm in the resampling stage, and applies it to the COMPASS/INS integrated navigation system. In order to verify the effectiveness of the proposed algorithm, the paper compares the improved UPF algorithm with the traditional UPF algorithm and then gives quantitative analysis of the experiment＇ s result through the relative time, the state estimation error and the mean square error. The simulation results show that, compared with the traditional UPF, the improved UPF can not only effectively shorten the operation time of the integrated navigation system, but also improve the positioning accuracy and the stability.