Evaluation of a regional real-time precise positioning system based on GPS/BeiDou observations in Australia

Abstract

The performance of real-time (RT) precise positioning can be improved by utilizing observations from multiple Global Navigation Satellite Systems (GNSS) instead of one particular system. Since the end of 2012, BeiDou, independently established by China, began to provide operational services for users in the Asia-Pacific regions. In this study, an regional RT precise positioning system in Australia is developed to evaluate the performance of GPS/BeiDou observations in providing high precision positioning services for users. Fixing three hourly updated satellite orbits, RT correction messages are generated and broadcasted by processing RT observation/navigation data streams from AUSCORS at the server side. At the user side, RT PPP is realized by processing RT data streams and the RT correction messages received. RT clock offsets, for which the accuracy reached 0.07 and 0.25 ns for GPS and BeiDou, respectively, can be determined. Based on these corrections, an accuracy of 12.2, 30.0 and 45.6 cm in the North, East and Up directions was achieved for the BeiDou-only solution after 30 minutes while the GPS-only solution reached 5.1, 15.3 and 15.5 cm for the same components at the same time. A further improvement of 43.7, 36.9 and 45.0 percent in the three directions, respectively, was achieved for the combined GPS/BeiDou solution. After the initialization process, the North, East and Up positioning accuracies were 5.2, 8.1 and 17.8 cm, respectively, for the BeiDou-only solution, while 1.5, 3.0, and 4.7 cm for the GPS-only solution. However, we only noticed a 20.9% improvement in the East direction was obtained for the GPS/BeiDou solution, while no improvements in the other directions were detected. It is expected that such improvements may become bigger with the increasing accuracy of the BeiDou-only solution.

Continuity Enhancement Method for Real-Time PPP Based on Zero-Baseline Constraint of Multi-Receiver

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An algebraic method for moving source localization using TDOA, FDOA, and differential Doppler rate measurements with receiver location errors

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“…Then, replace W 1 and covðθ 1 Þ in (40) by (27) and (29), substitute W 2 in (47) by (40), the inverse of (47) can be further approximately rewritten as…”

Vulnerabilities and integrity of precise point positioning for intelligent transport systems: overview and analysis

“…In addition to IGS and ACs, other institutes also provide real-time products with comparable accuracies (Ding et al 2018;Fu et al 2019), as well as some companies which provide their commercial users with real-time PPP services (Jokinen et al 2018;Leandro et al 2011;Liu 2018;Tobías et al 2014). Apart from satellite orbit and clock corrections, some of these companies also provide global/regional ionospheric corrections and/or regional tropospheric corrections.…”