Progress in studies on ISAR signal processing methods in NUAA

The main progress in studies on ISAR signal processing in Nanjing University of Aeronautics and Astronautics (NUAA) in recent years is described, including the observation model of radar imaging based on the view-point of multiple scatter-point localization, the simultaneous motion compensation and image formation based on the ML principle. The modified Doppler centroid tracking phase compensation, the superresolution range-Doppler imaging, and the multiple moving target resolution and imaging based on the ML principle and time-frequency analysis, respectively. Real data have been acquired in a series of field tests of an experimental ISAR. Three kinds of aircraft, including propeller plane and jet plane were involved in the tests. High quality images of the aircraft were obtained. Also, multiple moving target resolution is demonstrated using real data in field test of a narrowband coherent radar for estimating the number of aircraft in formation flight