Imaging and Detection of Moving Targetsbased on Spaceborne Video SAR Mode

Video synthetic aperture radar (Video SAR, ViSAR) is a new imaging mode, which can realize continuous observation over the interesting area with the radar operated in spotlight mode for an extended period of time, acquiring sequential SAR images with different squint angles. ViSARprocessing mode is analyzed in detail at first. The result shows thatecho data overlappingmodecanmeet the demand of ViSAR frame rate, ensuring fluency of avideo. Then moving targetsazimuth velocity and range velocity detection method is roughly introduced, respectively. After that, arefinedimproved fastback projection (BP) algorithm is proposed in detail. Fast BP algorithm can avoid unnecessary calculation for the overlapping data to realizeViSAR's high effectiveness. It can not only save resources, but also improve computing efficiency. Moreover, the obtained sequential SAR images can be used to estimate moving target velocity. Simulation results are provided to validate the effectiveness of the proposed algorithm.