Magnetic recording as a communications channel

Summary form only given. An often used model for a digital magnetic recording channel is to describe the input as a continuous waveform that takes on only one of two values (say +A and -A) and to describe the output as the sum of a linearly filtered version of the input and independent Gaussian noise. One aim of the article is to explain how this simple model need to be modified to take into account some of the important phenomena that occurs in high density recording. A second aim is to describe some of the coding schemes that are presently being used (or are about to be used) in digital recording systems