We studied the magnetic read/write channel with a magnetoresistive (MR) rea
d head at a normalized channel density range of 2.5-3.0, observing and mode
ling partial erasure and nonlinear transition shift. The asymmetry of the M
R head had a significant effect on the channel. We applied the transition-w
idth-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 nonlin
ear MR head model into the read/write channel, These modified models achiev
ed higher accuracy. Of all the models considered, the Volterra model provid
es the largest improvement over the linear model.