Diffraction modeling for interactive virtual acoustical environments

Since the dimensions of many of the objects/surfaces encountered in our daily lives are within an order of magnitude of the wavelength of audible sounds, diffraction is an elementary means of sound propagation. Despite its importance in the real-world, diffraction effects are often overlooked by acoustical modeling methods leading to a degredation in immersion or presence. This paper describes an acoustical diffraction method based on the Huygens-Fresnel principle. The method is simple and efficient allowing it to be incorporated in interactive acoustical environments including virtual environments. Experimental results are presented that illustrate the performance and effectiveness of the method and its conformance to theoretical diffraction models.