Abstract：To realize the high-resolution wide-swath mapping capability of spaceborne SAR, this paper presents a parabolic cylinder reflector based MIMO SAR system. According to the analysis of system configuration and Short-Term Shift-Orthogonal (STSO) transmitting waveforms, the specific processing method are elaborated. Taking advantage of parabolic characteristics in elevation, the narrow beams with high gain can be easily realized by the parabolic cylinder reflector. This facilitates the efficient separation of STSO transmitting waveforms by using the digital beam-forming technique, therefore, more azimuth equivalent phase centers can be obtained. After the multichannel reconstruction processing in azimuth, the echo signals from illuminated scene can be imaged by conventional imaging algorithms. The simulation results show that, the proposed system has satisfactory performance for MIMO SAR imaging.
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