A Survey on Cooperative Positioning Using GNSS Measurements

With the advancements of communication technologies and the Global Navigation Satellite Systems (GNSS), research and development in GNSS-based Cooperative Positioning (CP) is growing increasingly due to its potential of performance improvement compared to single-agent positioning. This paper presents a comprehensive survey that provides an overview of the state-of-the-art works on GNSS-based CP, categorizing them into six blocks: architecture, data sharing, measurements, estimation algorithms, performance evaluation, and integrity monitoring. Multiple solutions for each block are analyzed and compared if possible. Given that GNSS faces challenges mainly in urban areas, such as non-line-of-sight (NLOS), multipath, and cycle-slip, the discussions primarily focus on vehicular networks within urban environments. Finally, the challenges of practical applications and academic experiments of GNSS-based CP are discussed, and some potential research directions are outlined.