An Airborne SAR with 0.1 m Resolution Using Multi-channel Synthetic Bandwidth

In order to meet the growing demands for high resolution SAR imaging, this paper describes a new single channel transmit, multi-channel parallel receive high resolution SAR system. The system operates with 8 parallel receive channels to obtain a wide bandwidth up to 3.2 GHz, and also features high resolution, InSAR and PolSAR imaging capability. A novel method of transfer error measurement and compensation is presented in the paper. This method based on radiation calibration and frequency shift correction estimation could implement multi-channel amplitude and phase correction effectively. For the first time in China, a resolution of better than 0.1 m is achieved with the airborne SAR system. This paper introduces the architecture and main specifications of the SAR system, and discusses several important aspects of high resolution imaging in detail, including the bandwidth synthesis, transfer error correction, motion compensation and image formation. Flight experiments demonstrate the high resolution imaging capability of the SAR system.