Non-uniformly sampled signal reconstruction of DPC-MAB FMCW SAR based on fractional fourier transform

Combining Frequency-Modulated Continuous-Wave Synthetic Aperture Radar (FMCW SAR) and Displaced Phase Center Multi-beam in Azimuth (DPC-MAB) technology together can realize high-resolution wide-swath SAR imaging and take the advantages of FMCW SAR in the same time. However, when the platform velocity deviates from the theoretical speed, the azimuth signal will be periodic non-uniformly sampled which will produce ambiguities in azimuth direction; therefore the non-uniformly sampled signal must be reconstructed. In this article the non-uniformly sampled signal of DPC-MAB FMCW SAR is presented, and the non-uniformly sampled signal reconstruction algorithm based on Fractional Fourier Transform (FrFT) is introduced to reconstruct the non-uniformly sampled signal.