US 5,847,892 A · Servoing and formatting magnetic recording tape in an arcuate scanner system

Abstract

An arcuate scanner in accord with the invention records information on a longitudinal tape in a predetermined format. The format includes a top servo region and a lower servo region approximately twice as wide as one data track width. The top servo region contains a burst of recorded servo signal at a predetermined location. The lower servo region contains another burst of recorded servo signal at a predetermined location. Between each pair of top and lower servo regions, the information format includes two arcuate data tracks, containing a series of data blocks of a specified format. The locations of the servo bursts in the respective servo regions alternate between two lateral positions in adjacent servo tracks. During reading operations, a read head centered over one data track will pass both the servo regions around that data track and a portion of each of the servo regions around an adjacent track. A circuit samples the amplitude of the servo signal, taken during different time windows corresponding to passage over the various servo bursts in the two tracks. One or more relationships between the amplitudes of predetermined pairs of samples are used to produce one or more position error signals. Control elements, such as a tape drive motor and a position alignment controller (e.g. tilt motor) adjust the operation of the scanner system in response to the position error signal(s).

Claims17

Dependent claims

A method of controlling operations of a scanner system scanning a moving recording medium comprising the steps of:

passing a read head over a predetermined track recorded on the medium and partially overlapping a track adjacent the predetermined track on the medium;
determining a first time window and a second time window based on a detected passage of the read head over a detectable stripe that is prerecorded substantially along a length of the medium;
during the first time window in which the read head completely passes over a servo burst region of the predetermined track taking a first sample amplitude of servo burst signal from the read head;
during the second time window in which when the read head completely passes over a servo burst region of the adjacent track, taking a second sample amplitude of servo burst signal from the read head, wherein passage of the read head over the servo burst region of the adjacent track is excluded during the first time window and passage of the read head over the servo burst region of the predetermined track is excluded during the second time window;
and
controlling a parameter of operation of the scanner system in response to a relationship of the first sample amplitude to the second sample amplitude.

3 more elements

An arcuate scanning system, comprising:

an arcuate scanner having a plurality of scanner heads, the arcuate scanner performing read and write operations on a recording tape;
a circuit responsive to read signals from one of the heads for detecting signals of a predetermined frequency;
a circuit responsive to read signals from the head for detecting a passage of the head over a detectable stripe that is prerecorded substantially along a length of the recording tape, and determining a first time window and a second time window based on the detected passage of the head over the detectable stripe;
a circuit for (1) sampling amplitude of the detected signals of a predetermined frequency during the first time window to produce a first sample amplitude and (2) sampling amplitude of the detected signals of a predetermined frequency during the second time window to produce a second sample amplitude, wherein the signals detected during the first time window, in which the read head completely passes over the servo burst region of the predetermined track, are excluded from being detected during the second time window, in which the read head completely passes over the servo burst region of the adjacent track, and wherein the signals detected during the second time window are excluded from being detected during the first time window;
a circuit responsive to a relationship between the first and second sample amplitudes for generating a position error signal;
and
a control circuit for controlling at least one operational parameter of the arcuate scanning system in response to the position error signal.

4 more elements

Dependencies are inferred from the claim text.

Servoing and formatting magnetic recording tape in an arcuate scanner system

Life of this patent

Servoing and formatting magnetic recording tape in an arcuate scanner system

Life of this patent

Abstract

Claims17