PROJECT TITLE :

A Modified $omega$– $k$ Algorithm for HS-SAR Small-Aperture Data Imaging

ABSTRACT:

Thanks to the skew data support region (DSR) of the 2-D wavenumber spectrum for top-squint artificial aperture radar (HS-SAR), the standard $omega$– $k$ algorithm cannot absolutely utilize the DSR and so degrades the resolution if merely taking a rectangle region. Meanwhile, for the little-aperture knowledge, direct azimuth imaging in the gap domain can cause serious aliasing. A changed $omega$– $k$ algorithm springs during this paper to unravel these issues. The maximum usage of DSR is achieved by the coordinate rotation. As for the azimuth dependence, the strategy of azimuth resampling is employed to induce the uniform focusing. Totally different from the traditional $omega$– $k$ method, the modified $omega$– $k$ algorithm focuses the tiny-aperture knowledge in the azimuth wavenumber domain by SPECAN processing, that avoids padding a massive number of zeros when imaging in the azimuth distance domain. Simulated and real-information results show the validity and effectiveness of the presented algorithm.