Approximating the magnetic recording step response using a Voigt function

Abstract

A simple, closed-form expression for the step response or pulse shape of a magnetic recording channel is described. The step responses of inductive and magnetoresistive heads with thin-film media are shown to be well approximated by a Voigt function (the convolution of a Lorentzian and a Gaussian function). For convenience, an accurate approximation to the Voigt function (the linear superposition of a Lorentzian and a Gaussian function with appropriate weighting) was fit to the step responses using one adjustable parameter. The improved accuracy of this approximation to the step response has a strong impact on channel performance analysis and modeling.