Patent ID: 6839197
Filing Date: 2005-01-04
Classification: G11B

Abstract:
1. A method to calibrate a servo sensor disposed on a magnetic tape head disposed adjacent a magnetic tape moving along a tape path, wherein said magnetic tape includes at least one servo edge comprising an interface between a first recorded signal and a second recorded signal, wherein said servo sensor detects said first recorded signal and said second recorded signal, and wherein an independent position sensor provides an IPS signal comprising the position of said tape head with respect to said tape path, said method comprising the steps of: moving said tape head alternatingly in a first direction and an opposing second direction along a first axis as said tape moves along a second axis, wherein said first axis and said second axis are substantially orthogonal, wherein the position of said magnetic head along said first axis as a function of time comprises a periodic function having a reference frequency; providing an IPS signal; providing a servo signal comprising the ratio of said detected first recorded signal and said detected second recorded signal; establishing a sampling rate; sampling said servo signal at said sampling rate; sampling said IPS signal at said sampling rate; forming a measured servo signal waveform; forming a measured IPS signal waveform; determining the real components and the imaginary components of said measured servo signal waveform; forming a filtered servo signal waveform; determining the real components and imaginary components of said measured IPS signal waveform; forming a filtered IPS signal waveform; calculating a transfer function comprising the mathematical relationship between said filtered IPS signal waveform and said filtered servo signal waveform; and calculating one or more expected position error signals using said transfer function.