SAR image formation via semiparametric spectral estimation

A new algorithm, referred to as the SPAR (Semiparametric) algorithm, Is pre sented herein for target feature extraction and complex image formation via synthetic aperture radar(SAR). The algorithm is based on a flexible data m odel that models each target scatterer as a two-dimensional (2-D) complex s inusoid with arbitrary: unknown amplitude and constant phase in cross-range and with constant amplitude and phase in range. By attempting to deal with one corner reflector, such as one dihedral or trihedral, at a time, the al gorithm can be used to effectively mitigate the artifacts in the SAR images due to the flexible data model. Another advantage of SPAR is that it can b e used to obtain initial conditions needed by other parametric target featu re extraction methods to reduce the total amount of computations needed. Bo th numerical and experimental examples are provided to demonstrate the perf ormance of the proposed algorithm.