Browse Prior Art Database

Adjustment of Adaptive Digital Equalizer

IP.com Disclosure Number: IPCOM000037559D
Original Publication Date: 1989-Mar-01
Included in the Prior Art Database: 2005-Jan-29

Publishing Venue

IBM

Related People

Authors:
Galbraith, RL Kerwin, GJ [+details]

Abstract

This technique affords a means to provide independent coarse and fine adjustment to the adaptive equalizer used in a recording channel of a magnetic storage device. The coarse adjustment is made via an injected initial condition value (programmed), while the fine adjust is an adaptive (close loop) adjustment. The value programmed for each attempted read is derived from knowledge of the near optimum value gained from previous performance testing. This predetermined set of values can be chosen for each head and for various recording radius bands. The four bit coarse adjust value is loaded into the digital equalizer during an operation prior to a data read so that throughput performance is not compromised.