5G-Aided RTK Positioning in GNSS-Deprived Environments

This paper considers the localization problem in a 5G-aided global navigation satellite system (GNSS) based on realtime kinematic (RTK) technique. Specifically, the user's position is estimated based on the hybrid measurements, including GNSS pseudo-ranges, GNSS carrier phases, 5G angle-of-departures, and 5G channel delays. The underlying estimation problem is solved by steps that comprise obtaining the float solution, ambiguity resolution, and resolving the fixed solution. The analysis results show that the involvement of 5G observations can enable localization under satellite-deprived environments, inclusive of extreme cases with only 2 or 3 visible satellites. Moreover, extensive simulation results reveal that with the help of 5G observations, the proposed algorithm can significantly reduce the estimation error of the user's position and increase the success rate of carrier-phase ambiguity resolution.

I. Introduction

Accurate localization has become an essential requirement for a broad variety of applications, such as intelligent transportation, precision agriculture, surveying and mapping, and smart cities [1]–[3]. The development of advanced unmanned systems in recent years motivates a further increase in the demand for high positioning accuracy and reliability [4], [5]. Although plenty of navigation techniques have been developed for outdoor positioning, global navigation satellite system (GNSS)-based positioning is the most prevalent thanks to its advantages of high accuracy, global coverage, low cost, and all-weather capability.