ISAR imaging of space objects based on stepped frequency modulation

Inverse synthetic aperture radar (ISAR) imaging using stepped frequency modulation (SFM) signal is an important approach to achieve 2-dimensional high resolution. The range imaging method and the motion compensation method in ISAR imaging based on SFM signal are presented. The antidromic discarding method is adopted in range imaging to find a suitable starting point and to spell the range profiles. The least squares interpolation method based on prior information is used to estimate object´s range and velocity. The processing flow of the ISAR imaging approach base on the Range-Doppler method is showed. The final simulation results demonstrate that this approach can obtain high quality and high resolution 2-dimensional images.