ISAR imaging of uniformly rotating targets via parametric matching pursuit

Abstract

Inverse synthetic aperture radar (ISAR) imaging of maneuvering targets via matching pursuit (MP) can produce high resolution and remove sidelobe effect, providing that the target rotation rate is already known. For non-cooperative uniformly rotating targets, the rotation rate is unknown and should be retrieved together with the ISAR image. In this paper, a computational efficient parametric MP is proposed to simultaneously retrieve the rotation rate and the high-resolution ISAR image. The joint estimation of ISAR image and rotation rate is converted into alternate independent estimations, i.e. alternately estimating the ISAR image and rotation rate in an iterative manner. With the iterations, the rotation rate estimate converges to the true value and meanwhile the clear ISAR image with high resolution and low sidelobes may be obtained. Numerical examples show that the approach is efficient in estimating the real target rotation rate and recovering the high resolution ISAR image.