A high squint airborne SAR imaging algorithm with low PRF

In this paper, we analyze the geometry and the echo characteristic of the airborne squint mode Synthetic Aperture Radar (SAR), and propose an imaging algorithm which can adapt to the high squint case. Due to the large range-azimuth coupling, the spectrum of the rang-azimuth is tilted and a larger pulse repetition frequency (PRF) is needed to avoid azimuth ambiguities. This will increase the amount of calculation and decrease the swath width. Furthermore, the change of PRF will lead to spectrum folding. In this algorithm, a linear range cell migration correction (RCMC) is performed to correct the spectrum and an azimuth demodulation is taken to move the spectrum in the baseband. Finally, simulation results validate the effectiveness of the algorithm.