Outdoor sound propagation with analytic ray curve tracer and Gaussian beam.

Outdoor sound propagation benefits from algorithms that can handle, in a computationally efficient manner, inhomogeneous media, complex boundary surfaces, and large spatial expanse. One recent work by Mo, Yeh, Lin, and Manocha [Appl. Acoust. 104, 142-151 (2016)] proposed a ray tracing method using analytic ray curves as tracing primitives, which improved the performance of propagation paths computation over rectilinear ray tracers. In this paper, an algorithm is developed that extends the performance improvement to field computation; it combines the analytic ray curve tracer with fast pressure computation based on the Gaussian beam model. The algorithm is validated against published results on benchmarks in atmospheric and ocean acoustics, and its application is demonstrated on a scene with terrains and buildings of realistic complexity and under a variety of atmospheric conditions. This algorithm is able to compute characteristic sound fields for fully general media profiles and complex three dimensional scenes at close-to-interactive speed.