Exploiting temporal proximity for moving target identification using bistatic/passive SAR

Abstract

Geo-locating moving targets using sequential imaging while exploiting their spatio-temporal proximity is addressed in this paper for bistatic Linear Frequency Modulation (LFM) and Orthogonal Frequency-Division Multiplexing (OFDM) scenes. The approach consists of three major steps (i) Synthetic Aperture Radar/Along-Track Interferometry (SAR/ATI) imaging for moving target detection; (ii) target velocity estimation from ATI phase, and (iii) exploiting spatio-temporal connectivity using sub-aperture outputs for target geo-locations. The bistatic OFDM is more problematic than the bistatic LFM case because of the poor detection performance due to the presence of dominant target sidelobes. The results are demonstrated for various moving target sets in moderate clutter.