Vortex Radar Super-resolution Imaging Based on Iterative Adaptive Approach

The vortex radar transmits electromagnetic waves carrying orbital angular momentum (OAM), which obtains more azimuthal information than the plane wave, and has great application potential in the field of radar detection and imaging. However, the azimuth resolution is limited to OAM modes. In this paper, an iterative adaptive super-resolution method is proposed for vortex radar imaging. Firstly, the azimuthal targets detection problem is transformed into a parameter estimation problem, the echo autocorrelation matrix is reconstructed. Then the weighted cost function is updated iteratively based on the weighted least-squares criterion. Finally, the targets are obtained after iterations. Simulation results showed the effectiveness of the iterative adaptive approach on azimuth super-resolution of vortex radar with fewer OAM modes.