Ray Tracing Augmented With Monte Carlo Diffuse Scattering for Dense Multipath Components Simulation

Accurately modelling dense multipath components (DMCs) is essential for wireless propagation, yet traditional ray tracing (RT) becomes impractical when every diffuse reflection is enumerated. This letter augments conventional RT with a Monte Carlo diffuse scattering (MCDS) module that launches a single diffuse ray per interaction according to a prescribed probabilitydensity function and applies Russian-roulette termination, yielding an unbiased estimate of infinitely recursive diffuse paths while keeping the deterministic RT treatment of specular reflections. The fully RT-embedded formulation accommodates any physically realistic scattering pattern, including directive models. In a synthetic single-room scenario, MCDS preserves delayspread fidelity with near-constant run-time. Institute hallway measurements from the DICHASUS dataset further confirm that MCDS reproduces the diffuse tail more accurately than a hybrid propagation-graph approach, validating both its efficiency and predictive accuracy for high-frequency indoor propagation