Echo-Based SAR Imaging Simulation for Typical Target Assisted by Ray Tracing

To achieve high-fidelity synthetic aperture radar (SAR) simulated images of typical target, we propose an echo-based SAR imaging simulation method assisted by ray tracing. The method incorporates multiple scattering mechanisms and establishes a backscattering model under the far-field plane wave assumption. A ray tracing algorithm is employed to capture the amplitude and phase of multiple backscattering components from numerous microfacets distributed across the target surface. The total backscattering field is then computed through vector superposition. Based on the principle of azimuthal synthetic aperture, we account for the real-time relative motion between the sensor and the target. A global phase correction is performed by leveraging the slant range history. This process transforms the local far-field scattering phase, which is referenced to the target modeling center, into a globally coherent scattering field. Then, the target’s global backscattering field is accurately reconstructed and serves as the raw echo signal. The range-Doppler (RD) imaging algorithm is subsequently applied to focus the simulated echo signal and generate the final SAR image. We select a typical aircraft carrier target for testing evaluation. The target is placed in the beam radiation scene and subjected to multi-angle rotation to produce corresponding multi-angle simulated SAR images. Qualitative and quantitative comparisons are conducted against both the RaySAR commercial software and real SAR image to verify the effectiveness of the proposed method.