Abstract:

Rotor synthetic aperture radar (ROSAR) is a new mode of imaging radar. Under the condition of high resolution, range cell migration (RCM) has significant effects on the image. The wavenumber-domain imaging algorithm involves precise RCM correction by means of interpolation, but it is hard to use interpolation for two-dimensional wavenumber spectrum acquired by the traditional wavenumber-domain method, due to the complex expression of distance history. To deal with this problem, a modified wavenumber-domain imaging algorithm for ROSAR is proposed. The wavenumber vector is rebuilt in azimuthal angle domain, the 2-D wavenumber spectrum which is proper to perform interpolation can be obtained by solving implicit function, the reference function is designed to eliminate effects from high frequency modulation, the well-focused image and RCM correction with no approximation for wide-beam and large-scale scene are obtained by Stolt interpolation. The simulation results validate the effectiveness and feasibility of the proposed algorithm.