Joint Estimation of Vehicle's Position and Velocity With Distributed RSUs for OFDM Radar System

Abstract

We develop a vehicle motion state estimation algorithm based on an orthogonal frequency division multiplexing radar system suitable for vehicle-to-infrastructure (V2I) communications scenarios. Due to the transverse movement with respect to the direction from the target to roadside unit (RSU), the measured velocity is distorted as the Doppler shift depends on the angle formed between the vehicle position and RSU. To compensate for the distorted velocity, the exact vehicle position is required. However, this cannot be obtained in a system with a single RSU. In this paper, we develop an efficient cooperative vehicle state estimation algorithm that reduces the number of RSUs required for localization compared to conventional schemes by eliminating unnecessary RSUs to overcome the degradation of target detection performance in low signal-to-noise ratio regimes. Furthermore, the singularity problem due to the absence of Doppler shift when the vehicle travels near the tangential direction can be addressed with spatially distributed RSUs. Numerical results verify that the proposed estimation algorithm outperforms the existing schemes in V2I scenarios.