Nonlinear digital circuits and waveshaping are active areas of study,
specifically for what concerns numerical and aliasing issues. In
the past, an effective method was proposed to discretize nonlinear
static functions with reduced aliasing based on the antiderivative of
the nonlinear function. Such a method is based on the continuoustime convolution with an FIR antialiasing filter kernel, such as a
rectangular kernel. These kernels, however, are far from optimal
for the reduction of aliasing. In this paper we introduce the use
of arbitrary IIR rational transfer functions that allow a closer approximation of the ideal antialiasing filter, required in the fictitious continuous-time domain before sampling the nonlinear function output. These allow a higher degree of aliasing reduction and
can be flexibly adjusted to balance performance and computational
cost.