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公开(公告)号:EP2862170A4
公开(公告)日:2015-08-12
申请号:EP13806537
申请日:2013-06-18
Applicant: IBM
Inventor: PANTAZI ANGELIKI , BUI NHAN XUAN , JELITTO JENS
CPC classification number: G11B5/584
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公开(公告)号:JP2001067847A
公开(公告)日:2001-03-16
申请号:JP2000215615
申请日:2000-07-17
Applicant: IBM
Inventor: BUI NHAN XUAN , FUKUDA JUNICHI , JAQUETTE GLEN ALAN , KOSKI JOHN ALEXANDER , TSURUTA KAZUHIRO
Abstract: PROBLEM TO BE SOLVED: To obtain a data detection method and a data detection apparatus for performing robust detection of data modulated into a servo pattern of a timing base. SOLUTION: First, a timing interval between sequential change stripes is detected, and then, an interval comparison logic circuit 112 determines whether '0' or '1' is represented. Thereafter, a first counter 106 increments the number of the compared intervals that represent '0', while a second counter 107 increments the number of the compared intervals that represent '1'. Then, a bit comparison logic circuit 123 compares the incremented number with a predefined reference value 122 for every frame. When either one is fitted to the reference value 122, the corresponding '0' or '1' is identified as a bit value for the frame.
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公开(公告)号:JP2001006140A
公开(公告)日:2001-01-12
申请号:JP2000139485
申请日:2000-05-12
Applicant: IBM
Inventor: BUI NHAN XUAN , FUKUDA JUNICHI , JAQUETTE GLEN ALAN , KOSKI JOHN ALEXANDER , TSURUTA KAZUHIRO
Abstract: PROBLEM TO BE SOLVED: To effectively and precisely identify the serve gap by dividing a detected group timing gap by a specified divisor, feeding a timing interval gap detection threshold, and measuring the timing intervals between detected transition stripes. SOLUTION: A divider 170 divides a detected group B timing interval by a specified divisor to output a divided timing interval gap detection threshold. The divisor is selected by a divisor selector 174 to generate longer thresholds than the timing interval between transition stripes of burst one by one, and this involves values for generating shorter thresholds than the timing intervals of a min. interval gap at the edge of a servo pattern. A servo gap output value of a comparator 110 is fed back to an interval counter 120, and the count is fixed to latch the detection. When a pulse detector 122 detects the next stripe transition, the interval counter is reset to zero again.
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公开(公告)号:GB2490219B
公开(公告)日:2014-07-16
申请号:GB201206620
申请日:2011-01-20
Applicant: IBM
Inventor: HANCOCK REED ALAN , BUI NHAN XUAN , TSURUTA KAZUHIRO , JUDD KEVIN BRUCE , INCH RANDY CLARK
IPC: G11B5/584
Abstract: A servo detection system for detecting servo tracks of a longitudinal tape. In a read/write head, two servo read heads are spaced laterally on a first head module, and a servo read head is on a second head module spaced longitudinally from the first module. A method comprises initially sensing a tape servo track with one servo read head of the first module and the servo read head of the second module to determine skew misalignment of the servo track. A zero reference value is stored representing the determined skew misalignment. The detection system switches from the one servo read head of each module, to the two servo read heads of the first module, and employs the stored value to position the read/write head in the zero skew position. The two servo read heads are then employed to read two servo tracks to identify the data band and to control skew.
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公开(公告)号:CA2874225A1
公开(公告)日:2013-12-27
申请号:CA2874225
申请日:2013-06-18
Applicant: IBM
Inventor: PANTAZI ANGELIKI , BUI NHAN XUAN , JELITTO JENS
Abstract: A tape drive configured to accurately position a head actuator in the presence of physical disturbances is disclosed. The tape drive includes a track-follow controller to position a head actuator over data tracks on magnetic tape. The tape drive further includes a disturbance observer configured to estimate a vibration disturbance and output a compensation signal to assist the track- follow controller to accurately position the head actuator over the data tracks in the presence of vibration. When estimating the vibration disturbance, the disturbance observer takes into account vibration frequency characteristics, such as frequency characteristics derived from a vibration specification associated with the tape drive, or frequency characteristics derived from known vibration disturbances experienced by the tape drive. A corresponding method is also disclosed.
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公开(公告)号:DE112011102447T5
公开(公告)日:2013-06-13
申请号:DE112011102447
申请日:2011-07-14
Applicant: IBM
Inventor: HANCOCK REED ALAN , INCH RANDY CLARK , TSURUTA KAZUHIRO , OGURA EIJI , NADE-HARA SHUHEI , BUI NHAN XUAN
Abstract: Offenbart wird ein Verfahren zum Betrieb eines Magnetbandlaufwerks. Das Bandlaufwerk weist eine Vielzahl von Gleichstrommotoren auf, von denen jeder eine Vielzahl von Hall-Sensoren aufweist und unter der Steuerung eines Servosystems steht, das so konfiguriert ist, dass es Positionsangaben vom Magnetband liest. Das Servosystem berechnet eine primäre Bandgeschwindigkeit aus der Positionsangabe und erfasst ein sekundäres und ein tertiäres Geschwindigkeitssignal und berechnet anhand dieser eine Bandgeschwindigkeit. Wenn die Positionsangabe der primären Geschwindigkeit verfügbar ist, wird sie verwendet, wenn nicht, wird eines von dem sekundären oder tertiären Geschwindigkeitssignal verwendet. Das sekundäre Geschwindigkeitssignal wird verwendet, wenn ein Absolutwert eines auf die Bandgeschwindigkeit bezogenen Terms kleiner als ein vorbestimmter Wert ist, und das tertiäre Geschwindigkeitssignal wird verwendet, wenn ein Absolutwert des auf die Bandgeschwindigkeit bezogenen Terms größer als der vorbestimmte Wert ist.
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公开(公告)号:CA2874225C
公开(公告)日:2020-09-22
申请号:CA2874225
申请日:2013-06-18
Applicant: IBM
Inventor: PANTAZI ANGELIKI , BUI NHAN XUAN , JELITTO JENS
Abstract: A tape drive configured to accurately position a head actuator in the presence of physical disturbances is disclosed. The tape drive includes a track-follow controller to position a head actuator over data tracks on magnetic tape. The tape drive further includes a disturbance observer configured to estimate a vibration disturbance and output a compensation signal to assist the track- follow controller to accurately position the head actuator over the data tracks in the presence of vibration. When estimating the vibration disturbance, the disturbance observer takes into account vibration frequency characteristics, such as frequency characteristics derived from a vibration specification associated with the tape drive, or frequency characteristics derived from known vibration disturbances experienced by the tape drive. A corresponding method is also disclosed.
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公开(公告)号:DE112011100154T5
公开(公告)日:2012-10-04
申请号:DE112011100154
申请日:2011-02-18
Applicant: IBM
Inventor: CHERUBINI GIOVANNI , HANCOCK REED ALAN , JELITTO JENS , TSURUTA KAZUHIRO , BUI NHAN XUAN
IPC: G11B5/584
Abstract: Ein veränderliches Zeitintervall wird von einem zeitabhängigen Servoband erfasst, um die seitliche Position eines Servolesekopfs zu ermitteln. Das Servoband ist in einer Folge von Blöcken mit nichtparallelen Servostreifen in sequenziell angrenzenden Unterrahmen eines linearen Magnetbands angeordnet. Die Zeitintervalle umfassen mindestens ein erstes Zeitintervall (A) zwischen einem ersten Paar nichtparalleler Servostreifen eines Unterrahmens; und ein veränderliches Zeitintervall (C) zwischen einem Paar nichtparalleler Servostreifen zwischen den ersten Zeitintervallen (A), wobei die Servostreifen des veränderlichen Intervalls der sequenziell angrenzenden Unterrahmen einen zweiten Servostreifen des ersten Paars und einen ersten Servostreifen eines sequenziell nachfolgenden ersten Paars umfassen. Bei Positionssignalen handelt es sich um Verhältnisse, an denen das erste und das zweite Zeitintervall beteiligt sind.
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公开(公告)号:GB2487135A
公开(公告)日:2012-07-11
申请号:GB201200428
申请日:2010-09-13
Applicant: IBM
Inventor: PANTAZI ANGELIKI , ELEFTHERIOU EVANGELOS , JELITTO JENS , BUI NHAN XUAN
IPC: G11B5/584
Abstract: Various embodiments for addressing time-varying periodic disturbances in a servo control system are provided. Each of a plurality of coefficients is updated based on an estimation of at least one disturbance frequency. The updated plurality of coefficients is provided to at least one peak filter modifying an input signal of the servo control system. The peak filter is operable in view of the updated plurality of coefficients to cancel at least 10 one of the time-varying periodic disturbances.
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公开(公告)号:CZ297495B6
公开(公告)日:2007-01-03
申请号:CZ20014146
申请日:2000-05-18
Applicant: IBM
Inventor: BUI NHAN XUAN , JAQUETTE GLEN ALAN , KOSKI JOHN ALEXANDER , TSURUTA KAZUBIRO
Abstract: Systém a způsob je určen pro přesnou registraci a synchronizaci datových skupin na záznamovémédium, které má předem zaznamenaný servo vzorek. Záznamové médium je podrobeno souvislémupohybu pro čtení a/nebo zápis datových skupin, přerušenému zastavením na konci zvolené datové sady a nově spuštěnému. Během souvislého pohybu záznamového média detektor připojenýk servo systému souvisle čte registrační datas lineární pozicí modulovaná do předem zaznamenaného servo vzorku. Interpolátor interpoluje předem zaznamenaná registrační data k zajištění přesných registračních informací pro datové skupiny. Poté co pohon zastaví záznamové médium, pak provede jednorázový posun zpět média a obnoví pohyb, jsou zajištěny zvolené přečtené a interpolované registrační informace.Detektor znovu přečte a interpoluje předem zaznamenaná registrační data a komparátor porovná znovu přečtené a interpolované registračníinformace se zajištěnými přečtenými a interpolovanými registračními informacemi a libovolný předem stanovený ofset, a indukuje shodu porovnání. Datový formátovač (54) připojený ke komparátoru (150), reagující na indikaci shody porovnání, synchronizuje čtení a/nebo zápis datových skupin na záznamové médium (70).
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