The method of ISAR image modulation based on corner reflector with phase-switched screen

In order to solve the problem of limited protection area and lack of flexibility of passive protection means against inverse synthetic aperture radar (ISAR) imaging reconnaissance, an inverse synthetic aperture radar (ISAR) image modulation method based on phase-switched screen (PSS) corner reflector is proposed. The ISAR imaging characteristics of the mutual-spin corner reflector structure with and without PSS period modulation are analyzed, and the jamming characteristics of the mutual-spin corner reflector structure on ISAR images are revealed. Based on the expansion requirements of jamming area in the distance direction, the spectrum characteristics of PSS bipolar modulation waveform and triangular-stepped phase modulation waveform are analyzed, and different jamming strategies are designed. Simulation experiments are designed to analyze the jamming effect of different modulation signals loaded on the mutual-spin PSS corner reflector structure. The simulation results show that the jamming extent of the mutual-spin corner reflector structure is limited only by its physical size without PSS modulation, and according to different strategies, the jamming extent can be extended to 3−7 times. The simulation results are consistent with the theoretical analysis. This method combines the advantages of active jamming and passive jamming, which means a simple structure, low cost, low exposure and flexible application. With the method, aerial targets equipped with small passive protection devices can countermine ISAR imaging reconnaissance.