An Improved RD Imaging Algorithm for FMCW SAR

As a kind of high resolution radar, Synthetic Aperture Radar (SAR) is very important in many military applications. Frequency modulated continuous wave (FMCW) synthetic aperture radar (SAR), combining FMCW technique with synthetic aperture imaging methods, is a newly proposed imaging radar system, and has the advantages such as small cubage, light weight, cost-effective, high-resolution, etc. However, for FMCW SAR, the platform continuously moves while transmitting and receiving signal. The duration of the transmitted pulse increases. The stop-and-go approximation is invalid. So the proper algorithms have to be used to achieve the expected results. For the peculiarity of FMCW SAR, the signal processing is deduced in detail when stop-and-go approximation is invalid, and a modification to RD is presented in order to compensate Doppler frequency shift. The simulation results are finally presented.