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公开(公告)号：GB2490778A
公开(公告)日：2012-11-14
申请号：GB201207690
申请日：2011-02-18
Applicant: IBM
Inventor： HANCOCK REED ALAN , BUI NHAN XUAN , JELITTO JENS , CHERUBINI GIOVANNI , TSURUTA KAZUHIRO
IPC: G11B5/584
Abstract: An alternative time interval is taken of a timing based servo band to determine lateral position of a servo read head. The servo band is arranged in a sequence bursts with non- parallel servo stripes in sequentially adjacent sub-frames of a linear tape. The timing intervals comprise at least a first time interval (A) between a first pair of non-parallel servo stripes of a sub-frame; and an alternative time interval (C) between a pair of non-parallel servo stripes intermediate the first time intervals (A), the alternative interval servo stripes of sequentially adjacent sub-frames comprising a second servo stripe of the first pair, and a first servo stripe of a sequentially succeeding first pair. Position signals are ratios involving the first and second time intervals.
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52.发明专利
公开(公告)号：DE112010002334T5
公开(公告)日：2012-08-02
申请号：DE112010002334
申请日：2010-06-02
Applicant: IBM
Inventor： JELITTO JENS , HUTCHINS ROBERT ALLEN , SANDBERG MELANIE JEAN , CHERUBINI GIOVANNI
IPC: G11B5/584
Abstract: Verfahren zur Überwachung einer Vielzahl von Servokanälen, Bereitstellen eines endlichen Automatens (FSM) umfassend eine Einzelservokanal-Betriebsart und eine kombinierte Servokanal-Betriebsart und Bewegen eines sequenziellen Informationsspeicherungsmediums, das eine Vielzahl von Servobändern umfasst, über einen Lese-/Schreibkopf, der eine entsprechende Vielzahl von Servosensoren umfasst. Das Verfahren setzt ferner einen Erfassungsflag durch einen Servokanal, wenn dieser Servokanal einem Servomuster folgt, und ersetzt einen Bitflag durch einen Servokanal, wenn ein neuer LPOS-Bit decodiert wurde. Wenn zumindest ein Erfassungsflag gesetzt ist, bestimmt das Verfahren, ob ein Bitflag durch einen mit dem gesetzten Erfassungsflag assoziierten Servokanal gesetzt wurde, und ob ein Erfassungsflag und ein Bitflag durch einen Servokanal gesetzt wurde. Das Verfahren bestimmt eine relative Positionierung jedes Servosensors in Bezug auf ein assoziiertes Servomuster.
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公开(公告)号：CA2780235A1
公开(公告)日：2011-09-01
申请号：CA2780235
申请日：2011-01-19
Applicant: IBM
Inventor： CHERUBINI GIOVANNI , JELITTO JENS , LANTZ MARK A , HUTCHINS ROBERT A
IPC: G11B5/584
Abstract: Timing based servo bursts of servo frames, in which the frames are arranged to be symmetric with the same number of servo stripes in each burst of a frame, are synchronized by shifting selected bits. For example, servo frames are arranged with four servo bursts with an equal number of servo stripes in each burst, the servo frames comprising two symmetric sub-frames, each sub-frame comprising two bursts of servo stripes that are parallel to each other within a burst, and the bursts are non-parallel with respect to each other; each servo burst is arranged to comprise at least one reference servo stripe; and each servo burst is arranged to comprise at least one shifted servo stripe, wherein the shift is in the same longitudinal direction with respect to at least one reference servo stripe for each burst of a frame and the opposite longitudinal direction for bursts of sequentially adjacent frames.
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公开(公告)号：CA2765148A1
公开(公告)日：2011-01-13
申请号：CA2765148
申请日：2010-06-02
Applicant: IBM
Inventor： JELITTO JENS , CHERUBINI GIOVANNI , HUTCHINS ROBERT ALLEN , SANDBERG MELANIE JEAN
IPC: G11B5/584
Abstract: A method for monitoring a plurality of servo channels, providing a finite state machine ("FSM") comprising a single servo channel mode and a combined servo channel mode, and moving a sequential information storage medium comprising a plurality of servo bands across a read/write head comprising a corresponding plurality of servo sensors. The method further asserts an acquisition flag by a servo channel if that servo channel is tracking a servo pattern, and asserts a bit flag by a servo channel if a new LPOS bit is decoded. If at least one acquisition flag is asserted, the method determines if a bit flag is asserted by a servo channel associated with said asserted acquisition flag, and if an acquisition flag and a bit flag are asserted by a servo channel, the method determines a relative positioning of each servo sensor with respect to an associated servo pattern.
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公开(公告)号：DE602006009123D1
公开(公告)日：2009-10-22
申请号：DE602006009123
申请日：2006-07-03
Applicant: IBM
Inventor： ELEFTHERIOU EVANGELOS , OELCER SEDAT , JAQUETTE GLEN ALAN , JELITTO JENS , HUTCHINS ROBERT ALLAN
Abstract: A read channel and method using that read channel are disclosed. The read channel comprises an analog to digital converter which asynchronously samples at a fixed rate an analog signal formed by reading a data track, where that data track was written to a data storage medium at a symbol rate and an interpolator interconnected with the analog to digital converter. The read channel further comprises a fractionally-spaced equalizer, where the interpolator provides an interpolated signal to the fractionally-spaced equalizer at an interpolation rate, where that interpolation rate is greater than the symbol rate. The fractionally-spaced equalizer forms a synchronous equalized signal. The read channel further comprises a gain control module interconnected with the fractionally-spaced equalizer, and a sequence detector interconnected with the gain control module.
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Patent Agency Ranking
公开(公告)号：AT442651T
公开(公告)日：2009-09-15
申请号：AT06792475
申请日：2006-07-03
Applicant: IBM
Inventor： ELEFTHERIOU EVANGELOS , OELCER SEDAT , JAQUETTE GLEN , JELITTO JENS , HUTCHINS ROBERT
Abstract: A read channel and method using that read channel are disclosed. The read channel comprises an analog to digital converter which asynchronously samples at a fixed rate an analog signal formed by reading a data track, where that data track was written to a data storage medium at a symbol rate and an interpolator interconnected with the analog to digital converter. The read channel further comprises a fractionally-spaced equalizer, where the interpolator provides an interpolated signal to the fractionally-spaced equalizer at an interpolation rate, where that interpolation rate is greater than the symbol rate. The fractionally-spaced equalizer forms a synchronous equalized signal. The read channel further comprises a gain control module interconnected with the fractionally-spaced equalizer, and a sequence detector interconnected with the gain control module.
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公开(公告)号：DE602004006537T2
公开(公告)日：2008-01-31
申请号：DE602004006537
申请日：2004-11-19
Applicant: IBM
Inventor： FURRER SIMEON , JELITTO JENS , SCHOTT WOLFGANG , WEISS BEAT
Abstract: The invention relates to a method for modulating sub-carrier symbols to an intermediate-frequency OFDM signal having even and odd samples, including following steps: transforming a number N of the sub-carrier symbols to pre-processed sub-carrier symbols; performing a complex inverse discrete Fourier transformation (IDFT) on the pre-processed sub-carrier symbols to generate complex output symbols; and transforming the complex output symbols to the intermediate-frequency OFDM signal, wherein the sub-carrier symbols are transformed so that the even and odd samples of the intermediate-frequency OFDM signal are given by real and imaginary parts of the complex output symbols.
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公开(公告)号：DE60302160T2
公开(公告)日：2006-07-13
申请号：DE60302160
申请日：2003-06-17
Applicant: IBM
Inventor： JELITTO JENS , NOLL BARRETO ANDRE , TRUONG LINH
Abstract: The present invention discloses an apparatus and method for adapting a transmission parameter in a transmitting node of a data communication system to the current link quality of a data communication channel. The adapted transmission parameter is selected by the transmitting node from a set of transmission parameters in dependence on a number of successful transmissions. The number of successful transmissions is compared in the transmitting node against one of a first threshold value corresponding to a first state of the transmitting node and a second threshold value corresponding to a second state of the transmitting node. The method comprises in the transmitting node the steps of (a) counting the number of successful transmissions; (b) selecting the adapted transmission parameter (b1) in response to the number of successful transmissions equaling or exceeding the first threshold value when the transmitting node is in the first state, and (b2) in response to the number of successful transmissions equaling or exceeding the second threshold value when the transmitting node is in the second state; and in dependence of the result of a following transmission, operating the transmitting node in one of the first state and the second state.
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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：CA2780235C
公开(公告)日：2018-05-29
申请号：CA2780235
申请日：2011-01-19
Applicant: IBM
Inventor： CHERUBINI GIOVANNI , JELITTO JENS , LANTZ MARK A , HUTCHINS ROBERT A
IPC: G11B5/584
Abstract: Timing based servo bursts of servo frames, in which the frames are arranged to be symmetric with the same number of servo stripes in each burst of a frame, are synchronized by shifting selected bits. For example, servo frames are arranged with four servo bursts with an equal number of servo stripes in each burst, the servo frames comprising two symmetric sub-frames, each sub-frame comprising two bursts of servo stripes that are parallel to each other within a burst, and the bursts are non-parallel with respect to each other; each servo burst is arranged to comprise at least one reference servo stripe; and each servo burst is arranged to comprise at least one shifted servo stripe, wherein the shift is in the same longitudinal direction with respect to at least one reference servo stripe for each burst of a frame and the opposite longitudinal direction for bursts of sequentially adjacent frames.
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