Generation of High-Quality Spaceborne Interrupted FMCW SAR Images via Singular Value Threshold-Based Matrix Completion

The concept of spaceborne interrupted frequency-modulated continuous-wave (IFMCW) synthetic aperture radar (SAR) subverts the design principles of the traditional frequency-modulated continuous-wave (FMCW) SAR system, which uses a single physical antenna to transmit signal and receive echo alternatively. Due to the demand of turning off the receiver in the process of transmitting signal, periodical data-missing phenomena will be aroused in the echo data, and the missing ratio is close to 50%. When traditional imaging algorithms were used to process the echo data, the artifacts, appearing as periodically replicated false targets, will be generated in the focused SAR image due to the periodical missing data, thus affecting the image interpretation. In order to effectively suppress the artifacts, a novel method exploiting singular value threshold-based matrix completion (SVT-MC) technology was proposed in this letter, where the singular value decomposition of the Hankel matrix was utilized to recover the missing data with high precision. Finally, the experimental results based on both point targets and distributed targets verify the effectiveness and superiority of the proposed method.