Open Access

Digital Waveguides versus Finite Difference Structures: Equivalence and Mixed Modeling

EURASIP Journal on Advances in Signal Processing20042004:561060

Received: 30 June 2003

Published: 27 June 2004


Digital waveguides and finite difference time domain schemes have been used in physical modeling of spatially distributed systems. Both of them are known to provide exact modeling of ideal one-dimensional (1D) band-limited wave propagation, and both of them can be composed to approximate two-dimensional (2D) and three-dimensional (3D) mesh structures. Their equal capabilities in physical modeling have been shown for special cases and have been assumed to cover generalized cases as well. The ability to form mixed models by joining substructures of both classes through converter elements has been proposed recently. In this paper, we formulate a general digital signal processing (DSP)-oriented framework where the functional equivalence of these two approaches is systematically elaborated and the conditions of building mixed models are studied. An example of mixed modeling of a 2D waveguide is presented.

Keywords and phrases

acoustic signal processinghybrid modelsdigital waveguidesscatteringFDTD model structures

Authors’ Affiliations

Laboratory of Acoustics and Audio Signal Processing, Helsinki University of Technology


© Karjalainen and Erkut 2004