导航定位精度与所选卫星数目多少有关,而卫星数目过多虽可改善定位精度,但带来巨大的运算量。通过研究行列式绝对值与几何精度因子的关系,给出改进选星算法,且将该算法应用于双星定位系统中,并对比分析两种不同组合卫星数目下定位精度,以及运算量大小。结果表明改进选星算法运算量小,定位精度高,且用最小二乘算法在5次迭代后定位误差非常小,表明改进选星算法的可行性。

Navigation positioning accuracy is related with the number of satellite, although too much satellite can improve positioning accuracy, but this may cause huge computation. By studying the relationship between absolute value of determinant and geometric dilution of precision, an improved satellite selection algorithm was presented, which was applied to combined constellation system, and the positioning accuracy in different combination satellite number was analyzed. Simulation results indicate that improved satellite selection algorithm has low computational complexity, high positioning accuracy, and positioning error is very small by using least squares algorithm after 5 iterations, all of these can indicates the feasibility of improved algorithm.