一种北斗混合系统单点定位随机模型的优化方法

针对北斗混合系统中不同轨道类型、BDS-2/BDS-3卫星间观测值的差异,提出利用基于北斗UERE的Helmert方差分量估计模型对北斗混合系统定位的随机模型进行优化。对基于等权模型、普通Helmert方差分量估计模型及本文提出的优化模型进行单点定位实验,从定位精度与定位成功率上对3种模型的解算结果进行对比分析。结果表明,相比于等权模型和普通Helmert方差分量估计模型,优化模型能提高在E、N、U方向上的定位精度,同时减少因卫星星座空间几何构型较差而导致的定位精度较低的情况,从而提高定位成功率。

An Optimization Method for Single Point Positioning Stochastic Model of Beidou Hybrid System

Abstract: There is a difference between the different orbit types and BDS-2/BDS-3 satellites observation values in the Beidou hybrid system, so this paper proposes a method, based on Helmert variance component estimation model of Beidou UERE, to optimize the stochastic model of the Beidou hybrid system. The single point positioning experiments based on the equal weight model, the ordinary Helmert variance component estimation model, and the proposed optimization model are carried out. The calculation results of the three models are compared and analyzed with respect to the positioning accuracy and the positioning success rate. The results show that the proposed optimization model has high positioning accuracy on the E, N and U directions compared with the equal weight model and the ordinary Helmert variance estimation model. It can reduce situations in which the positioning accuracy is low due to the poor spatial geometry of the satellite constellation, and it improves the positioning success rate.