High Accuracy Multi-Antenna Ranging Algorithm and Performance Analysis for FMCW Radar

This paper categorizes existing single-antenna ranging algorithms for Frequency Modulated Continuous Wave (FMCW) radar based on the maximum likelihood principle into frequency, phase, and coherent methods and extends them to cover multi-antenna regimes. A new frequency compensation beamforming algorithm for multi-antenna ranging is proposed, which can achieve micron-level ranging accuracy compared to multi-antenna ranging algorithms without frequency compensation. The paper also derives the Cramér-Rao Bounds (CRBs) for distance estimation of the single-antenna ranging algorithms and the multi-antenna ranging algorithms. Finally, simulation experiments verify the correctness of the CRBs derived in this paper. The proposed multi-antenna ranging algorithms achieve the theoretical CRBs in Root Mean Square Error (RMSE) and demonstrate higher ranging accuracy compared to their single-antenna counterparts.