🤖 AI Summary
To address the low computational efficiency, high memory overhead, and elevated noise in far-field electromagnetic scattering simulation of complex multilayer dielectric materials, this paper proposes an enhanced Shooting-and-Bouncing Rays (SBR) method integrating Monte Carlo integration with variance reduction techniques. For the first time, advanced variance reduction strategies from computer graphics rendering are incorporated into the SBR framework to explicitly emphasize high-contribution propagation paths, model multipath effects and long-range reflections. Coupled with GPU-accelerated parallelization, the method overcomes traditional SBR bottlenecks in numerical integration and memory consumption. Validation on 3D canonical models and aircraft targets in ISAR imaging demonstrates a 10–15× reduction in memory usage and a 4× speedup in computation, while preserving low noise levels and high accuracy. The proposed approach significantly enhances downstream electromagnetic imaging fidelity and quantitative analysis capability.
📝 Abstract
We introduce a Monte Carlo integration-based Shooting and Bouncing Ray (SBR) algorithm for electromagnetic scattering, specifically targeting complex dielectric materials. Unlike traditional deterministic SBR methods, our approach is the first to reformulate the SBR integral equations using Monte Carlo techniques and advanced variance reduction strategies adapted from photorealistic rendering. This enables efficient, massively parallel computation on modern GPUs, resulting in up to a 10-15x reduction in memory usage and a 4x speed up in runtime, particularly for multilayer dielectric structures. Our method emphasizes high-energy propagation paths, efficiently capturing long multipath and interreflection effects. Verification on canonical 3D geometries and ISAR imaging of both conducting and dielectric representative aircraft models demonstrates that our Monte Carlo SBR achieves high accuracy while maintaining low noise, making it suitable for downstream imaging and analysis tasks.