First-Order Rear-Wall Multipath Positioning and Suppression for Through-Wall Imaging Radar

This paper deals with the positioning and suppression problem for the first-order rear-wall multipath ghosts exploiting a time-division multiple-input multiple-output through-wall imaging radar (TWIR). Based on the specular reflecting assumption, the positions of the multipath ghosts are obtained mathematically, and the defocusing of the multipath ghosts in TWIR image is proved theoretically. In addition, a correlation-weighted sub-aperture-based multipath suppression algorithm is proposed to subdue the first-order rear-wall multipath ghosts, improving the quality of the TWIR image significantly. Numerical simulations and experimental data verify the positioning theory and validate the proposed algorithm.