By Reproduced Control Signal Patents (Class 360/73.12)
  • Patent number: 9390759
    Abstract: An apparatus for operating a tape storage device comprises a tape skew estimation unit for estimating a value related to a skew of a tape storage medium arranged in the tape storage device relative to a head module of the tape storage device. A servo pattern decoder is configured to decode information encoded in a servo pattern written to one or more servo bands of the tape storage medium based on read-back signals of at least two servo readers of the tape storage device arranged for reading the servo pattern from the one or more servo bands and based on the estimated skew related value.
    Type: Grant
    Filed: April 6, 2015
    Date of Patent: July 12, 2016
    Assignee: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: Giovanni Cherubini, Simeon Furrer, Jens Jelitto, Kazuhiro Tsuruta
  • Patent number: 9177571
    Abstract: In a method for operating a tape storage system, readback signals are simultaneously received from a set of data readers reading from data tracks of a set of adjacent data tracks extending along a longitudinal extension of a tape storage medium, wherein each data track of the set has a width and each data reader of the set has a width equal to or less than the width of a data track. Simultaneously to receiving the readback signals from the set of data readers readback signals are received from a servo reader arrangement containing at least one servo reader arranged laterally offset from one of the data readers by less than the width of a data track. At least one of lateral position, velocity, gain and timing information is determined dependent on the readback signals of each servo reader in the servo reader arrangement.
    Type: Grant
    Filed: September 17, 2014
    Date of Patent: November 3, 2015
    Assignee: International Business Machines Corporation
    Inventors: Giovanni Cherubini, Simeon Furrer, Jens Jelitto, Mark A. Lantz
  • Patent number: 8780484
    Abstract: A method according to one embodiment includes setting a default friction value to a predetermined value, determining whether a primary velocity is valid, determining a velocity error, determining whether the velocity error is in a predetermined range, accumulating the velocity error when the velocity error is determined to be in the predetermined range, repeating, until a time period has elapsed, each of: the determining the velocity error, the determining whether the velocity error is in the predetermined range, and the accumulating the velocity error when the velocity error is determined to be in the predetermined range, and calculating a new friction value based on the accumulated velocity error.
    Type: Grant
    Filed: August 30, 2012
    Date of Patent: July 15, 2014
    Assignee: International Business Machines Corporation
    Inventors: Reed A. Hancock, Randy C. Inch, Eiji Ogura
  • Patent number: 8488267
    Abstract: A system and method for positioning a sensor relative to a storage medium. A system includes a first sensor and a second sensor arranged so that a point of a storage medium traverses each sensor at a different time. A processor is coupled to the sensors. The processor varies the timing of a sample representing a noise signal received from the sensors in accordance with medium velocity. The processor adjusts the position of the sensors based on the sample.
    Type: Grant
    Filed: June 6, 2008
    Date of Patent: July 16, 2013
    Assignee: Hewlett-Packard Development Company, L.P.
    Inventor: Donald J. Fasen
  • Publication number: 20090219645
    Abstract: A method to decode linear position (“LPOS”) information encoded in a sequential information storage medium, by detecting each of one or a plurality of sequential first LPOS servo patterns encoded in a first servo band using a first servo sensor in communication with a first servo channel. While detecting that one or a plurality of first LPOS servo patterns, the method fails to detect (n) second LPOS servo patterns encoded in a second servo band. The method determines a value for (n), and then syncs the first servo channel with the second servo channel using that value of (n).
    Type: Application
    Filed: February 29, 2008
    Publication date: September 3, 2009
    Applicant: INTERNATIONAL BUSINESS MACHINES CORPORATION
    Inventors: NHAN XUAN BUI, ROBERT ALLEN HUTCHINS, MALANIE JEAN SANDBERG, KAZUHIRO TSURUTA
  • Patent number: 7480114
    Abstract: A fully synchronous servo channel for a data tape drive is provided which includes the initial acquisition of synchronous servo channel parameters, generation of a timing basis for signal interpolation, generation of a tape velocity estimate and a y-position estimate and an optimum detection of longitudinal position (LPOS) symbols embedded in servo bursts.
    Type: Grant
    Filed: March 8, 2008
    Date of Patent: January 20, 2009
    Assignee: International Business Machines Corporation
    Inventors: Giovanni Cherubini, Evangelos Eleftheriou, Robert Allan Hutchins, Jens Jelitto
  • Patent number: 7365929
    Abstract: A fully synchronous servo channel for a data type drive is provided which includes the initial acquisition of synchronous servo channel parameters, generation of a timing basis for signal interpolation, generation of a tape velocity estimate and a y-position estimate and an optimum detection of longitudinal position (LPOS) symbols embedded in servo bursts.
    Type: Grant
    Filed: July 30, 2006
    Date of Patent: April 29, 2008
    Assignee: International Business Machines Corporation
    Inventors: Giovanni Cherubini, Evangelos Eleftheriou, Robert Allan Hutchins, Jens Jelitto
  • Patent number: 7245450
    Abstract: A fully synchronous longitudinal position (LPOS) detection system is provided for improving the reliability of servo channels in tape systems. The system is based on the interpolation of the servo channel output signal, which is sampled by an analog-to-digital converter (ADC) at a fixed sampling rate, using a clock at a nominal frequency, so that interpolated signal samples are obtained at a predetermined fixed rate, independent of tape velocity. This predetermined fixed rate is defined in terms of samples per unit of length, as opposed to samples per unit of time, which is the measure of the ADC sampling rate. The resolution with which the servo channel signal is obtained at the interpolator output is thus determined by the step interpolation distance.
    Type: Grant
    Filed: January 26, 2006
    Date of Patent: July 17, 2007
    Assignee: International Business Machines Corporation
    Inventors: Giovanni Cherubini, Evangelos S. Eleftheriou, Robert A. Hutchins, Jens Jelitto
  • Publication number: 20030016466
    Abstract: A method and apparatus for performing position error signal conditioning of LTO media servo format written-in velocity variation is disclosed. According to the present invention only the signals demonstrating velocity deviations are filtered. A magnetic recording tape includes servo signal bursts of flux transitions recorded thereon. The servo bursts include a configuration of stripes of A spacings and B spacings and a servo head disposed proximate the magnetic recording tape senses the flux transitions of the servo signal bursts. A servo controller, coupled to the servo head, receives the sensed signals from the servo head. The servo controller further includes a filter for filtering the B time interval servo signal components.
    Type: Application
    Filed: July 17, 2001
    Publication date: January 23, 2003
    Applicant: International Business Machines Corporation
    Inventors: Nhan X. Bui, John Alexander Koski, Akimitsu Sasaki, Kazuhiro Tsuruta
  • Patent number: 6301069
    Abstract: A servo control apparatus controls operation of a to-be-controlled object through execution of software based on control data and reference data. An operation-signal generating portion generates an operation signal having a frequency representing the operation of the to-be-controlled object. A clock-signal generating portion generates a clock signal having a frequency controlled in accordance with the control data. A counting portion measures a time corresponding to the period of the operation-pulse signal by counting pulses of the clock signal, and generates a count value. A controlling portion controls the operation of the to-be-controlled object through execution of software based on the count value and the reference data.
    Type: Grant
    Filed: September 29, 1998
    Date of Patent: October 9, 2001
    Assignee: TEAC Corporation
    Inventor: Eiji Ueda
  • Patent number: 6236526
    Abstract: A sealed audio cassette player for playing a single permanently installed audio tape. The player is primarily intended for use with cassettes containing a spoken book, such as the Bible. In one embodiment, frequency indicia are provided on the tape for indicating tape linear speed. A drive motor drives the cassette take up spindle at a predetermined tape linear speed of less than about 0.5 inch per second with rotation of the drive motor varied in accordance with the indicia to maintain a constant tape linear speed. In an alternate embodiment a drive motor drives the cassette take up reel at a constant speed, so that the speed of movement of the tape past an audio pickup head constantly varies. The cassette is recorded with an identical constant speed take up, so that only cassettes so made will work in the player. The cassette is recorded with an identical constant speed take up, so that only cassettes so made will work in the player.
    Type: Grant
    Filed: September 28, 1998
    Date of Patent: May 22, 2001
    Inventors: Harvey Hoekstra, Mark Hoekstra
  • Patent number: 6198588
    Abstract: The present invention relates to apparatus for reading and writing data to a storage medium, wherein the data is written to the medium in tracks, each track having a predetermined trigger signal pattern, the apparatus comprising: structure for detecting the predetermined trigger signal pattern; an adaptive filter for signals read from the medium; and structure for triggering adaptive filtering for a track of data on detection of the predetermined trigger signal pattern in that track. In this way, during a read operation adaptive filtering is triggered on commencement of data with spectral characteristics suitable for adaption of the filter. In the embodiment to be described, each track comprises data fragments each having a header containing ancillary information wherein at least a header in an initial data fragment in the track comprises the predetermined trigger signal pattern. Preferably, at least the header of the initial data fragment in the track comprises the predetermined trigger signal pattern.
    Type: Grant
    Filed: September 23, 1997
    Date of Patent: March 6, 2001
    Inventor: Stephen Langford