Modeling a class of multi-port nonlinearities in wave digital structures

Abstract

Wave Digital Structures (WDS) are particularly interesting for applications of interactive modeling of nonlinear (NL) elements in the context of Virtual Analog modeling. NL circuits, however, often include multiple nonlinearities or multi-port nonlinearities, which cannot readily be accommodated by traditional WDS. In this work we present a novel method for modeling in the WD domain a class of multi-port NL elements that are obtained as the interconnection of linear and NL resistive bipoles. Our technique is based on a Piece-Wise Linear approximation of the individual bipoles that constitute the multi-port element. The method generalizes the existing solutions that are available in the literature as it enables the modeling of arbitrary interconnections between outer ports of the nonlinearity and individual ports of the local NL bipoles.