Non-linear identification on the digital magnetic recording channel

The authors describe a method for identifying the digital magnetic recording channel in which data dependent nonlinear effects are present. The method can be extended to any discrete-input, discrete-time channel with finite memory. The channel is considered as a finite state machine or lookup table, in which the number of states is related to the memory length of the channel. The model parameters are derived by using linear least-squares estimation or by adaptation of the model to minimize mean-squared error. A simple linear transformation is used to convert the finite state machine outputs to the coefficients of a Volterra series model. The results of the channel identification process are shown