A Spatially Variant Point Spread Function for Near-field Radar Image Simulation

Conventional radar image simulation requires electromagnetic (EM) scattering data over two-dimensional (2D) domain of wideband frequencies and observation angles. The repeated EM scattering calculation results in high computation complexity. In this work, a fast technique for 2-D near-field radar image simulation based on the shooting and bouncing ray (SBR) is proposed. Under the narrow band and small angle approximations, a closed form expression for the spatially variant point spread function (SVPSF) is derived to compute image domain contributions of the ray tubes. Simulation results demonstrate that the correlation coefficient between the radar images generated using the proposed fast technique and the conventional technique are over 0.98.