PHY Layer for 5G Radio-Based Precise Positioning in 5GCAR Vulnerable Road User

New 5G communication systems will have much higher bandwidth enabling new applications. One of those application is higher accuracy localization which in turn will support autonomous driving and protection of vulnerable road users (VRU), like pedestrians. Such applications require localization accuracies of approximately 1 m for the VRU and for the vehicles. Localization accuracies of roughly 1 cm are possible with GNSS (Global Navigation Satellite Systems) that employ RTK (Real Time Kinematic), but in dense urban environments, multipath impairments and the lack of visible satellites limits the usefulness of these systems. Current 4G systems lack the accuracy needed for the VRU application. Larger 5G bandwidth offer the potential for new functionalities and significant higher localization accuracy. However, terrestrial based localization remains a challenge due to impairments such as multipath, Non-Line of Sight (NLoS) conditions, poorly synchronized base stations, and inaccurate knowledge of the location of the base station antennas. To address these issues, we have engaged in an EU-funded project, 5GCAR [1], and demonstrate new radio-based positioning features through synchronized sniffer nodes. In this paper we present the details of the system that makes accurate Time of Arrival (ToA) possible, lab tests to evaluate the system performance, and a field trial on a real test track in Linas-Montlhéry, France.