BDS/GPS差分系统间偏差估计算法及性能分析

基于BDS/GPS单频紧组合相对定位模型,提出联合卡尔曼滤波与粒子滤波估计差分系统间偏差(DISB)的算法,并利用实测短基线数据对比分析卡尔曼滤波算法与本文算法估计DISB的效果。实验表明,载波DISB的整数部分会影响参考卫星站间单差模糊度的估计,从而影响载波DISB小数部分的估计结果;利用本文算法估计并改正DISB后得到的模糊度解算的可靠性和固定解精度均优于卡尔曼滤波,固定解精度最大可提高10%～20%。

Estimation Algorithm and Performance Analysis of the Differential Inter-System Bias of BDS and GPS

In this paper, based on the relative positioning model of BDS/GPS single-frequency tight combination, we propose a combination algorithm of Kalman filter and particle filter to estimate the differential inter-system bias (DISB) of BDS/GPS tightly combined, and then analyze the algorithm performance by contrast with Kalman filter algorithm using short baseline data. The results show that the integer part of the phase DISB can affect the estimation of the DISB fractional part by changing the single-differenced ambiguity of pivot satellite. Further, the DISB of the proposed algorithm estimation corrects the tight combination and can improve the reliability of ambiguity resolution and fixed solution precision. Fixed solution precision can be increased by 10%~20%.