Apply Super-SVA to SAR Imaging with Both Aperture Gaps and Bandwidth Gaps

Synthetic aperture radar (SAR) imaging usually requires echo data collected continuously pulse by pulse with certain bandwidth. However in real situation, data collection or part of signal spectrum can be interrupted due to various reasons, i.e. there will be gaps in spatial spectrum. In this case we need to find ways to fill out the resulted gaps and get image with defined resolution. In this paper we introduce our work on how to apply iterative spatially variant apodization (Super-SVA) technique to extrapolate the spatial spectrum in both azimuthal and range directions so as to fill out the gaps and get correct radar image.

Authors:

• Wenshuai Zhai
• Yunhua Zhang

Keywords:

• SAR imaging
• Sparse aperture
• Stepped frequencychirp signal
• high resolution
• Super-SVA

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