A Phase Grating Approach to Modeling Surface Diffusion in FDTD Room Acoustics Simulations

Journal article


Publication Details

Author(s): Kowalczyk K, van Walstijn M, Murphy D
Journal: IEEE Transactions on Audio Speech and Language Processing
Publication year: 2011
Volume: 19
Journal issue: 3
Pages range: 528-537
ISSN: 1558-7916
Language: English


Abstract

In this paper, a method for modeling diffusive boundaries in finite-difference time-domain (FDTD) room acoustics simulations with the use of impedance filters is presented. The proposed technique is based on the concept of phase grating diffusers, and realized by designing boundary impedance filters from normal-incidence reflection filters with added delay. These added delays, that correspond to the diffuser well depths, are varied across the boundary surface, and implemented using Thiran allpass filters. The proposed method for simulating sound scattering is suitable for modeling high frequency diffusion caused by small variations in surface roughness and, more generally, diffusers characterized by narrow wells with infinitely thin separators. This concept is also applicable to other wave-based modeling techniques. The approach is validated by comparing numerical results for Schroeder diffusers to measured data. In addition, it is proposed that irregular surfaces are modeled by shaping them with Brownian noise, giving good control over the sound scattering properties of the simulated boundary through two parameters, namely the spectral density exponent and the maximum well depth.


FAU Authors / FAU Editors

Kowalczyk, Konrad Dr.
Professur für Nachrichtentechnik


How to cite

APA:
Kowalczyk, K., van Walstijn, M., & Murphy, D. (2011). A Phase Grating Approach to Modeling Surface Diffusion in FDTD Room Acoustics Simulations. IEEE Transactions on Audio Speech and Language Processing, 19(3), 528-537. https://dx.doi.org/10.1109/TASL.2010.2051830

MLA:
Kowalczyk, Konrad, M. van Walstijn, and D. Murphy. "A Phase Grating Approach to Modeling Surface Diffusion in FDTD Room Acoustics Simulations." IEEE Transactions on Audio Speech and Language Processing 19.3 (2011): 528-537.

BibTeX: 

Last updated on 2019-28-04 at 12:31