Low angle estimation in diffuse multipath environment by time-reversal minimum-norm-like technique

This study presents a novel method for low angle estimation in diffuse multipath environment by the time-reversal (TR) minimum-norm-like (MNL) technique. In recent studies, the diffuse multipath is always regarded as the interference which is tried to be eliminated or weakened in low angle estimation for very high-frequency radar. However, it is difficult to establish the accurate model of the multipath environment. The common methods usually ignore the diffuse multipath and use the mirror reflection as the approximate model, but the ideal assumption would cause great errors. The proposed method makes the radar array working in the TR setup and the MNL technique is applied to estimate the low angle. In the proposed method, the exact model of the multipath environment does not need to be established completely but the accuracy performance of low angle estimation can be improved by making use of the multipath. Simulation results are presented to demonstrate the effectiveness of the proposed method. In addition, the performance degradation with respect to target motion is also shown in simulation results.