Magnetoresistive read/write channel models

We studied the magnetic read/write channel with a magnetoresistive (MR) read head at a normalized channel density range of 2.5-3.0, observing and modeling partial erasure and nonlinear transition shift. The asymmetry of the MR head had a significant effect on the channel. We applied the transition-width-reduction model, the partial-erasure-plus-transition-shift model, and the Volterra model to the MR read/write channel, and evaluated the accuracy of these models on the basis of parameters obtained from experimental data. In order to consider the asymmetry of the MR head, we introduced a nonlinear MR head model into the read/write channel. These modified models achieved higher accuracy. Of all the models considered, the Volterra model provides the largest improvement over the linear model.