Ray tracing for efficient simulation of curved sound propagation paths: Towards real-time auralization of aircraft noise

Thanks to modern auralization methods, simulated aircraft flyovers can be experienced in virtual environments. Listening to such an auralization provides a more sophisticated impression of annoyance of aircraft noise in real scenarios than reading averaged sound pressure levels or noise maps. For proper auralization results, translation and refraction due to wind and to inhomogeneity of the atmosphere should be taken into account, which leads to curved sound propagation paths. However, state of the art auralization tools including these effects do not allow real-time simulations on CPUs. In this work, an efficient ray tracing tool for simulating curved propagation paths between an aircraft and a listener is introduced. The performance and limitations are discussed for a typical aircraft trajectory. The benchmark results suggest that real-time auralization of aircraft noise using ray tracing is possible if the processing of propagation paths in the overlying auralization framework is extended accordingly.