An energetic interpretation of nonlinear wave digital filter lookup table error (invited paper)

In this paper, we study error in wave digital filter nonlinearities from an energetic perspective. By ensuring that power dissipation corresponding to this error is non-negative, we respect the basic wave digital filter premise that errors should not correspond to an increase in system energy. In particular, this has implications for the formation of lookup tables and the choice of lookup table interpolation method. We give recommendations for both based on the sign and second derivative of the wave-domain function which is to be tabulated. These recommendations are used to study interpolation of a diode characteristic.