Collaborative Code-Based Differential GNSS for Multi-User Positioning

Helena Calatrava, Daniel Medina, and Pau Closas

Peer Reviewed

Abstract:	This paper introduces a collaborative differential GNSS (C-DGNSS) method designed to enhance positioning accuracy in scenarios with limited satellite visibility, relying solely on GNSS pseudorange measurements and requiring no interranging information. C-DGNSS exploits the correlation among single difference observations from multiple users to a common base station, which are not leveraged by conventional DGNSS. The estimation problem is formulated as an iterative weighted least squares (WLS) estimator, known to be optimal under the Gaussian assumption, and its variance lower bound is derived from the Cramer-Rao bound (CRB). C-DGNSS is compared ´ against conventional DGNSS and the ideal DGNSS bound, the latter assuming noiseless pseudorange measurements for the base station. Simulation results demonstrate that the proposed scheme outperforms standard DGNSS even with a single aiding user, approaching the ideal bound as the number of aiding users grows and their geometry improves. Accuracy gains of up to 28.5% are achieved. Index Terms—Differential GNSS, Collaborative Positioning, Cramer-Rao Bound
Published in:	2025 IEEE/ION Position, Location and Navigation Symposium (PLANS) April 28 - 1, 2025 Salt Lake Marriott Downtown at City Creek Salt Lake City, UT
Pages:	473 - 480
Cite this article:	Calatrava, Helena, Medina, Daniel, Closas, Pau, "Collaborative Code-Based Differential GNSS for Multi-User Positioning," 2025 IEEE/ION Position, Location and Navigation Symposium (PLANS), Salt Lake City, UT, April 2025, pp. 473-480.
Full Paper:	ION Members/Non-Members: 1 Download Credit Sign In