Accelerated, Memory-Efficient Far-Field Scattering Computation with Monte Carlo SBR

TL;DR

This paper presents a novel Monte Carlo-based SBR algorithm for electromagnetic scattering that significantly reduces memory usage and computation time, enabling efficient analysis of complex dielectric structures on GPUs.

Contribution

It introduces the first Monte Carlo reformulation of SBR integral equations with variance reduction, achieving high efficiency and accuracy for complex dielectric scattering problems.

Findings

Up to 10-15x memory reduction

4x faster runtime on GPUs

High accuracy with low noise in complex geometries

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.