一种基于定位误差的多星座快速选星算法

对于GPS/SBAS/QZSS/BDS的多星座卫星导航系统,分别分析了几何精度因子(GDOP)与系统时间差以及与定位误差之间的关系,并在此基础上,进一步提出了一种快速选星算法。该算法基于定位误差进行选星,并考虑了系统时间差对GDOP的影响。仿真结果表明,该算法的计算量相对于最佳GDOP选星有了显著降低,选星后的GDOP值非常接近最佳GDOP选星的结果,从而在定位精度损失不大的条件下降低了定位解算的运算量。

A Fast Satellite Selection Algorithm Based on Positioning Error for Multi-constellation Satellite Navigation System

For GPS/SBAS/QZSS/BDS multi-constellation satellite navigation system, this paper analyzes the relationships between the Geometric Dilution of Precision (GDOP) value and system time bias as well as positioning error, respectively. According to the analysis, a fast satellite selection algorithm based on positioning error is further proposed. The effect of system time bias is taken into account in the algorithm. Simulation results show that, the computational complexity of the algorithm has reduced greatly compared with the best GDOP algorithm, and the GDOP value of the proposed algorithm is very close to that of the best GDOP algorithm after satellite selection. Thus, the proposed algorithm reduces the computational complexity of position solution at the expense of little position accuracy loss.