Richard Crane Schneider

An improved pulse-slimming method for magnetic recording

This paper briefly summarizes various pulse-slimming methods for enhancing magnetic recording signals. It then describes the compensation methods used in a recently announced mass storage system. The advantages of the new methods of compensation are compared with previous methods. A key feature of the new design is a basic pulse-slimming block that enables the leading and trailing edges of an isolated read pulse to be slimmed independently. This, combined with an integrator to convert peaks to zero crossings, equalizes the phase and amplitude of the recording channel.

Pulse compression recording

Small media defects are a major limitation to data reliability at high magnetic recording densities. One way of overcoming this limitation is to use an error correction code. In this paper, Pulse-Compression Recording (PCR) is proposed as a method in which the energy of each data bit is spatially dispersed in such a manner that the recorded information is insensitive to small media defects or short bursts of noise.