A Novel Wide Area Multiple Azimuth Beam ISAR Imaging System

A novel multiple azimuth beams (MAB) inverse synthetic aperture radar (ISAR) system, as well as, the corresponding processing algorithms are proposed in this paper, which is a promising technology for wide area surveillance (WAS). This system concept is intended to obtain wide area ISAR images of multiple moving targets, which would greatly increase the surveillance velocity range compared with the single beam system. The antenna transmits a sequence of high-gain and narrow radar beams to quickly scan a wide area, and receives the echoes from all the subswaths simultaneously. Two processing methods based on digital beamforming (DBF) are presented to separate the overlapped signals for achieving the wide area ISAR images. The performance of the proposed system is analyzed from the perspectives of the surveillance area, surveillance velocity range, and steering angle error. Finally, an exemplary ISAR system is presented and verified by the simulation experiments.