Research on the Weight Distribution of Helmert Variance Component Estimation in Beidou + 5G Integrated Positioning

摘要

In the complex environment of the city, the visible Beidou satellites are distributed along the road in a strip, which causes a significant decline in positioning performance. The high-density deployment of 5G systems provides an opportunity to improve the geometric distribution of satellites. However, due to the difference in the noise of the pseudo-range measurement between systems, there exists a large positioning error in the traditional solution to the least squares. As a result, this paper introduces the elevation prior determination weight and Helmert variance component estimation model to assign weights to Beidou and 5G systems to improve joint positioning accuracy. The simulation results show that compared to the equal weight model, the PDOP value is reduced by 11.76%, the circular probability error is reduced by 6.8%, and the positioning errors in the three directions of East North Down are reduced by 0.8%, 36.6% and 4.6% respectively. At the same time, the positioning stability has been improved.