Signal Reconstruction Approach for Multichannel SAR in Azimuth Based on Multiframe Super resolution

Abstract

To achieve high-resolution wide-swath imaging, the use of multichannel techniques in azimuth is effective for spaceborne Synthetic Aperture Radar (SAR). For azimuth multichannel systems, the signal in azimuth is nonuniformly sampled if the uniform sampling condition related to Pulse Repetition Frequency (PRF) is not satisfied, which makes it important to reconstruct the azimuth signal prior to image formation. In this study, to solve the azimuth signal reconstruction problem in multichannel SAR, we propose the innovative use of a multiframe super-resolution method in Digital Image Processing (DIP) and summarize the general multiframe super-resolution process. Our simulation results and real data experiments verify the effectiveness of the proposed method, which demonstrates some advantages in complexity performance. By establishing linkages between the problem of signal reconstruction of nonuniformly sampled signals and the multiframe superresolution concept, we provide a new approach to this traditional signal reconstruction problem.

Keywords

• Synthetic Aperture Radar (SAR)
• Azimuth multichannel
• High resolution wide swath
• Pulse Repetition Frequency (PRF)
• Nonuniform sampling
• Multiframe super-resolution