NONLINEAR CHANNEL MODELS FOR DIGITAL MAGNETIC RECORDING

We describe methods for identifying the digital magnetic recording channel in which data dependent nonlinear effects are present. The models that we use include the finite state machine (FSM), Volterra series and channel state dependent transition shifting. Procedures to compute the model parameters are described, and the models will be compared with a view to their accuracy and use for studying receiver performance. Results are included from prototype channels with various recording densities with significant nonlinear distortion