Estimating moving target information using single-channel synthetic aperture radar (SAR)

Simultaneously estimating position x and velocity v of moving targets using only the measured phase phi from single-channel SAR is impossible because the mapping from (x, v) to phi is many-to-one. This paper defines classes of equivalent target motion and solves the GMTI problem up to membership in an equivalence class using single-channel SAR phase data. Definitions are presented for endo-and exo-clutter that are consistent with the equivalence classes, and it is shown that most target motion can be detected, i.e. the set of endo-clutter targets is very small. We exploit the sparsity of moving targets in the scene to develop an algorithm to resolve target motion up to membership in an equivalence class, and demonstrate the effectiveness of the proposed technique using simulated data.