Sub-meter Level Initial Position Estimation for Multipath Mitigation in Deep Urban Environments (Using Time-Differenced Code-Minus-Carrier)

Yonghwan Bae, Hojoon Jeong, and Changdon Kee

Abstract:	The growing demand and market size for location-based services on various platforms have led to a significant increase in interest in navigation systems. To provide reliable services, navigation information from these systems must be robust against environmental changes to ensure precise and consistent performance. The most popular navigation system in use today is GNSS, and as positioning methods continue to develop, it is being used in many areas. However, receiving satellite signals remains difficult, especially in urban environments where the highest demand for services is found. In these areas, multipath errors caused by surrounding tall buildings significantly reduce the stability of the navigation system. This study presents a method for estimating and compensating for multipath errors in urban environments, using only measurements from a GNSS receiver, without the need for additional sensors or information. Specifically, we employ time-differenced CMC measurements to counteract the multipath error in the pseudorange measurements and achieve a level of accuracy comparable to that in open fields. Our experiments demonstrate an improved precision in estimating the initial position, addressing a common limitation in many urban navigation studies. The results of these preliminary tests suggest that a GNSS receiver alone could provide decimeter-level initial position information within urban centers. Furthermore, we show that the proposed method can be integrated with other urban precision positioning systems, as well as used for GNSS-only navigation in urban centers.
Published in:	Proceedings of the ION 2024 Pacific PNT Meeting April 15 - 18, 2024 Hilton Waikiki Beach Honolulu, Hawaii
Pages:	281 - 292
Cite this article:	Bae, Yonghwan, Jeong, Hojoon, Kee, Changdon, "Sub-meter Level Initial Position Estimation for Multipath Mitigation in Deep Urban Environments (Using Time-Differenced Code-Minus-Carrier)," Proceedings of the ION 2024 Pacific PNT Meeting, Honolulu, Hawaii, April 2024, pp. 281-292. https://doi.org/10.33012/2024.19599
Full Paper:	ION Members/Non-Members: 1 Download Credit Sign In