Open Access
ARTICLE
Modeling and Prediction of Inter-System Bias for GPS/BDS-2/BDS-3 Combined Precision Point Positioning
Zejie Wang1, Qianxin Wang1,*, Sanxi Li2
1
School of Environment Science and Spatial Informatics, China University of Mining and Technology, Xuzhou, 221116, China
2
Beijing Railway Electrification School, Beijing, 102202, China
* Corresponding Author: Qianxin Wang. Email:
(This article belongs to this Special Issue: Data Acquisition and Electromagnetic Interference Detection by Internet of Things)
Computer Modeling in Engineering & Sciences 2022, 132(3), 823-843. https://doi.org/10.32604/cmes.2022.020106
Received 04 November 2021; Accepted 11 January 2022; Issue published 27 June 2022
Abstract
The combination of Precision Point Positioning (PPP) with Multi-Global Navigation Satellite System (MultiGNSS), called MGPPP, can improve the positioning precision and shorten the convergence time more effectively
than the combination of PPP with only the BeiDou Navigation Satellite System (BDS). However, the Inter-System
Bias (ISB) measurement of Multi-GNSS, including the time system offset, the coordinate system difference, and
the inter-system hardware delay bias, must be considered for Multi-GNSS data fusion processing. The detected
ISB can be well modeled and predicted by using a quadratic model (QM), an autoregressive integrated moving
average model (ARIMA), as well as the sliding window strategy (SW). In this study, the experimental results
indicate that there is no apparent difference in the ISB between BDS-2 and BDS-3 observations if B1I/B3I signals
are used. However, an obvious difference in ISB can be found between BDS-2 and BDS-3 observations if B1I/B3I
and B1C/B2a signals are used. Meanwhile, the precision of the Predicted ISB (PISB) on the next day of all stations
is about 0.1−0.6 ns. Besides, to effectively utilize the PISB, a new strategy for predicting the PISB for MGPPP is
proposed. In the proposed strategy, the PISB is used by adding two virtual observation equations, and an adaptive
factor is adopted to balance the contribution of the Observed ISB (OISB) and the PISB to the final estimations of ISB.
To validate the effectiveness of the proposed method, some experimental schemes are designed and tested under
different satellite availability conditions. The results indicate that in open sky environment, the selective utilization
of the PISB achieves almost the same positioning precision of MGPPP as the direct utilization of the PISB, but the
convergence time of MGPPP is reduced by 7.1% at most in the north (N), east (E), and up (U) components. In
the blocked sky environment, the selective utilization of the PISB contributes to more significant improvement of
the positioning precision and convergence time than that in the open sky environment. Compared with the direct
utilization of the PISB, the selective utilization of the PISB improves the positioning precision and convergence
time by 6.7% and 12.7% at most in the N, E, and U components, respectively.
Keywords
Cite This Article
Wang, Z., Wang, Q., Li, S. (2022). Modeling and Prediction of Inter-System Bias for GPS/BDS-2/BDS-3 Combined Precision Point Positioning.
CMES-Computer Modeling in Engineering & Sciences, 132(3), 823–843.