A novel ISAR alogrithm for the imaging of ship targets based on AM-LFM model

Rang-Instaneous-Doppler (RID) processing is widely used in ISAR imaging of maneuvering target and acceptable image can be achieved when the amplitude modulation effect of scatterers echoes can be neglected during intergation time, whereas, the RID method based on the assumption above does not work properly when the variant amplitude modulation of scatterers´ echoes involved, such as ship target. In this paper, a multicomponent amplitude modulation and linear frequency modulation (AM-LFM) signal model developed and a fast parameter estimation technique-DechirpClean method proposed. To achieve the best quality in DechirpClean ISAR image, a new effective optimum imaging interval selection scheme addressed. The performance of proposed method is verified by comparing the result with the image produced by conventional RID method from the real data processing.