Space-Doppler processing for multichannel ISAR imaging of non-cooperative targets embedded in strong clutter

Abstract

Non-cooperative moving targets appear defocussed in SAR images and the blurring effect due to the unknown motion leads to low detection capabilities. In this work, clutter suppression and ISAR processing are combined to obtain well focused images of extended non-cooperative moving targets embedded in strong clutter, by exploiting Multichannel SAR (M-SAR) systems. Clutter mitigation and radar motion compensation are performed by means of the proposed Space Doppler Adaptive Processing. Then ISAR processing is used to compensate the unknown target motion. Two principal issues will be addressed. First, a technique to apply ISAR processing after clutter mitigation is presented, and then a suboptimal approach for clutter mitigation is proposed to overcome computational and statistical issues associated with estimation of clutter cross-power spectral matrix. Results of the processing applied to simulated data are provided in order to show the effectiveness of the proposed techniques.