Maximum likelihood synthetic aperture radar image formation for highly nonlinear flight tracks

This paper develops a flexible time-domain SAR imaging algorithm that is capable of accounting for somewhat arbitrary flight track geometries and platform orientations. The proposed technique casts SAR imaging as a maximum likelihood estimation problem where the ground reflectivities are taken as the parameters to be estimated. It is shown that conventional back projection is one of two steps required to form the optimal maximum likelihood image. Simulation examples are given that compare images and impulse response functions for back projection and the maximum likelihood algorithm.