SAR superresolution imaging algorithm based on Spatially Variant Apodization

The paper develops a new technique enhancing synthetic aperture radar (SAR) resolution as well as suppressing sidelobes based on adaptive weighting technique. Spatially Variant Apodization (SVA) is a nonlinear sidelobe reduction method without lose the resolution of mainlobe. The paper's method applies 2D SVA on the SAR image. And then it is detailed analyzed about the effect of extrapolated signal bandwidth after the processing. An inverse weight function is used to equalize the spectrum to obtain the extrapolated signal bandwidth. A modified noninteger Nyquist SVA formulation is used to suppress sidelobes after extrapolation. Examples of 1D case and 2D case demonstrate enhanced image resolution with sidelobe reduction.