Extended wavenumber domain algorithm for equivalent squinted linear frequency modulated continuous wave SAR imaging

Abstract. Ability to acquire high-resolution, phase-preserved images is an important requirement in modern synthetic aperture radar (SAR) applications. Wavenumber domain algorithms are good choices to achieve this objective without approximation in the wavenumber reversal process. However, when squint angle gets larger, even wavenumber domain algorithms suffer from resolution and computational efficiency degradations. In order to accommodate wavenumber domain algorithms to highly squinted SAR imaging by exploiting squint minimization and two-dimensional interpolation schemes, the proposed extended wavenumber domain algorithm possesses the advantages of maximum spectrum utilization, processing efficiency, and good interpretation of the two-dimensional interpolation. It can also be easily incorporated with motion compensation without complicating the motion analysis. Simulations and real data experiments validate our proposed algorithm.

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