Rotational motion compensation for wide-angle ISAR imaging based on integrated cubic phase function

To obtain high cross-range resolution in the inverse synthetic aperture radar (ISAR) image, it is necessary to increase the rotation angle of the target with respect to radar line of sight during the coherent integration interval. However, for a wide-angle target, the rotational motion will generate the migration through resolution cells (MTRC) inevitably which may lead to image defocusing in both the range and cross-range domain. The rotational motion compensation can be realized by two steps: the migration through range resolution cells (MTRRC) compensation and migration through cross-range resolution cells (MTCRRC) compensation. A new technique based on the integrated cubic phase function (ICPF) for the correction of MTCRRC in wide-angle ISAR imaging is addressed in this paper. The ICPF is an extension of the standard cubic phase function (CPF) to handle cases involving low signal-to-noise ratio (SNR) and multi-component LFM signals. Experiments with simulated data verify the validity of this algorithm.