Analysis of the performance of closely spaced low-cost multi-GNSS receivers

Chenyu Xue,Panos Psimoulis,Xiaolin Meng,Qiuzhao Zhang

doi:10.1007/s12518-021-00361-8

Abstract

The recent advances of low-cost GNSS receivers have broadened their application field not only in positioning and navigation, but also in deformation monitoring of civil engineering structures and geohazards. Even though some consumer-grade low-cost GNSS receivers can achieve cm-level accuracy, their lower performance compared to the dual-frequency high-end GNSS receivers restricts its systematic application of GNSS technology in monitoring projects. In this study, the noise level and performance of the low-cost GNSS receivers are assessed against geodetic receivers in terms of precision and availability when subjected to different measurements conditions, such as antenna grade, satellite constellation, and base station (antenna-receiver), based on zero- and short-baseline measurements. Furthermore, a new method is developed where a dual low-cost GNSS rover-system is formed by deploying two closely spaced low-cost GNSS receivers (30 cm apart), aiming to model their common error (multipath, satellite constellation, etc.) and reduce their noise level. The analysis of the zero- and short-baseline measurements reveals the potential improvement of the precision of the low-cost receiver by using multi-GNSS measurements and the importance of using a GNSS base station with geodetic antenna. However, development of a methodology which is based on adopting the sidereal filtering and the common mode error technique for the two closely spaced low-cost GNSS receivers may lead to precision of mm-level. The proposed methodology may broaden the application of low-cost GNSS receivers in monitoring networks and mainly for slowly developed deformations.

Highlights

The novelty of this study is that we developed a method where two low-cost GNSS receivers are combined in closely spaced formation and by applying combination of different approaches, the precision of lowcost GNSS receivers is enhanced significantly reaching even up to 1–2 mm-level, making more applicable for shortbaseline deformation monitoring applications
For the performance of the Leica receivers, it is generally observed that the two multi-GNSS solutions, GPS+GLONASS+Galileo and GPS+Galileo, result to the best precision regardless the antenna which was used
Potential weak geometry of GLONASS satellite constellation or problematic function of GLONASS satellite could result to lower precision of multi-GNSS solution, which was proved by Msaewe et al (2017)

Summary

Introduction

The GNSS technology has been established in the last decades for deformation monitoring applications, as the development of the GNSS receivers and processing methods led towards a more precise and accurate positioning, especially in shortbaseline (SBL) applications (Häberling et al 2015; MoschasThe recently developed commercial single-frequency lowcost GNSS receivers have improved performance achieving cm-level or even higher accuracy for static positioning (CinaAppl Geomat (2021) 13:415–435 and Piras 2015; Takasu and Yasuda 2009), and it is found that under favorable circumstances, such as long acquisition time, short baseline length, and use of external antenna, the difference between consumer-grade (u-blox 5T, etc) and geodetic grade receivers is not large (Cina and Piras 2015). The recently developed commercial single-frequency lowcost GNSS receivers have improved performance achieving cm-level or even higher accuracy for static positioning The difference in the design/configuration between the two types of the receivers/antennas results to the high noise level, low multipath resistance, and poor ambiguity resolution of the low-cost receiver relatively to the high-end GNSS stations (Takasu and Yasuda 2009). Recent studies have focused on the evaluation of the performance of the low-cost GNSS receivers in deformation monitoring (Caldera et al 2016; Jo et al 2013; Zhang and Schwieger 2016). Zhang and Schwieger (2016) analyzed the temporal and spatial correlation of an array of GPS stations consisted of low-cost receivers

Objectives

Results

Discussion

Conclusion