Efficient Raw Data Generation for Bistatic Sar Based on 2-D Inverse Wavenumber Mapping

摘要

Raw data generation of SAR echo is important for the evaluation of both imaging algorithms and SAR system design. Common time-domain echo generation methods (represented by projection method) are accurate for most of SAR modes but usually inefficient, while the existing FFT-based methods can only adapt to some relatively ideal configurations for bistatic SAR. Hence, this article will focus on FFT-based methods and try to solve the limitation of adaptability. For bistatic SAR with complicated configuration or maneuvering platform trajectories, 2-D spatial variation and difficulty on obtaining the 2-D spectrum of echo signal are the major problems to be faced with. To solve these problems, this article proposes an efficient raw data generation method based on 2-D inverse wavenumber mapping. This method first performs a 2-D FFT on the raw image to generate its 2-D wavenumber spectrum, then induces the space-variant phase using the 2-D inverse wavenumber mapping. Simulation results are presented to verify the validity of the proposed method.