Incorporating Inter-System Bias in Single Point Positioning Based on GPS, Galileo and BeiDou System

Dawid Łukasz Kwaśniak,Sławomir Cellmer

doi:10.7494/geom.2021.15.1.97

Dawid Łukasz Kwaśniak, Sławomir Cellmer

Open Access

https://doi.org/10.7494/geom.2021.15.1.97

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Abstract

The increasing number of satellites provides new opportunities. In the experiment presented in this paper, the Single Point Positioning technique is tested. Data from four different receivers were used in the tests. The GPS, Galileo and BeiDou System observations were collected over a three day long observational session. The computational process was carried out using self‑made software and point positions were obtained as the result. The goal of the test was to verify the impact of the Inter‑System Bias (ISB) on the final results. For this purpose, two cases of processing data were compared: with estimating ISB and without taking into account this parameter. In the paper the formulas of the mathematical models used are presented and, in both of the considered cases, a combination of GPS, BDS and Galileo was used. The results show that in the case where the ISB was taken into account, the accuracy and precision in the positioning was much better than in the approach where the ISB was not considered. Estimating the ISB allows for more precise positioning results to be obtained for car-navigation or GIS purposes.

Highlights

For many years, there were only two operating Global Navigational Satellite Systems (GNSS) – GPS and GLONASS
The results show that in the case where the Inter‐System Bias (ISB) was taken into account, the accuracy and precision in the positioning was much better than in the approach where the ISB was not considered
It is visible that the number of available Bei Dou System (BDS) satellites is higher in the NNOR and JFNG stations than in the case of GPS when on sta‐ tions WROC and WTZ2 number of BDS satellites is comparable with number of Galileo satellites, a result of the BDS constellation characteristics

Summary

Introduction

There were only two operating Global Navigational Satellite Systems (GNSS) – GPS and GLONASS. BDS will became fully operational in 2020 All satellites of this system are already in space, some of them are still in their test phase. For the MEO orbit planes period is Incorporating Inter‐System Bias in Single Point Positioning Based on GPS, Galileo. XCnC − xA ρCnC where in (2) and (3): xyzC, xyzE, xyzG are BDS, Galileo and GPS satellites coordinates, ρGA0, ρEA0, ρCA0 are geometric distances between approximate point position and satel‐ lites, n stands for the number of observable satellites, xyzA0 are approximate point co‐ ordinates.

Experiment Description

Experiment Results

Summary and Conclusions