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公开(公告)号：SG70556A1
公开(公告)日：2000-02-22
申请号：SG1996004914
申请日：1993-05-19
Applicant: IBM
Inventor： JAQUETTE GLEN ALAN , TAYEFAH MOROVAT
Abstract: A circuit for simultaneously detecting both MO and ROM signals reflected from an optical disk so that both signals are present and useable without switching from one to the other. The circuit eliminates switching time and switching transients. Two photodetectors are arranged to sense P and S components of polarized light in order to stimulate a differential amplifier and produce an output representative of MO recorded data. A second amplifier is connected to at least one of the photodetectors to produce an output representative of ROM recorded data and also representative of defects in the MO portion of the optical disk.
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公开(公告)号：ES2136112T3
公开(公告)日：1999-11-16
申请号：ES93300779
申请日：1993-02-03
Applicant: IBM
IPC: G11B7/004 , G11B7/00 , G11B7/0055 , G11B7/007 , G11B7/24 , G11B7/26 , G11B7/28 , G11B20/12 , G11B27/10
Abstract: The present invention relates to a data storage device comprising a circular disc (30), a data storage medium on at least one surface of the disc, a spiral track extending within the storage medium about the axis of the disc, and a plurality of data storage sectors formed on the track. According to the invention the storage device is characterised in that the storage medium is formed with a reference mark (100) extending radially from the axis of the disc, and the data storage sectors are arranged in groups extending along the spiral track, one end of each group of sectors being located adjacent to one of the points of intersection of the reference mark with the spiral track.
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公开(公告)号：DE69224936T2
公开(公告)日：1998-10-22
申请号：DE69224936
申请日：1992-06-16
Applicant: IBM
Inventor： CARDERO SILVIO ANTONIO , JAQUETTE GLEN ALAN
Abstract: When optical disk recorder having readback circuits is used with pulse width modulated (PWM) signals a phase error of a clocking system with respect to the phase of a data signal is used to generate an amplitude detection threshold offset for servoing of the amplitude detection threshold by the phase error signals tending to increase the probability of faithful detection of data carried by the PWM or other signals.
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公开(公告)号：DE69119855D1
公开(公告)日：1996-07-04
申请号：DE69119855
申请日：1991-09-16
Applicant: IBM
Inventor： BACA FRANCISCO ANTONIO , FENNEMA ALAN AUGUST , HANCOCK REED ALAN , JAQUETTE GLEN ALAN , TIPTON LAWRENCE DAVID , WINARSKI DANIEL JAMES
IPC: G11B7/00 , G11B7/0037 , G11B7/004 , G11B7/09 , G11B7/125 , G11B11/105 , G11B19/04 , G11B19/28 , G11B27/36 , G11B33/10
Abstract: The present invention relates to a data storage system (12, 13, 14, 15) of the type which comprises loading means (17,18) for loading a removable data storage disk into the system, driving means for rotating a disk loaded into the system up to an operational speed of rotation, and calibrating means (11) for calibrating the system in accordance with a disc loaded into the system. According to the invention the data storage system is characterised in that the calibrating means comprises sensing means for sensing the speed of rotation of a disk loaded into the system, means responsive to the speed sensing means for indicating when the speed of rotation is at a predetermined value less than the operational speed of rotation, and means for performing selected calibration operations on the system when the speed of rotation of said disk loaded into the system has reached the predetermined value.
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公开(公告)号：GB2400972B
公开(公告)日：2005-12-14
申请号：GB0418054
申请日：2003-01-17
Applicant: IBM
Inventor： JAQUETTE GLEN ALAN , GRECO PAUL MERRILL , KARP JAMES MITCHELL
Abstract: Synchronized data is written to magnetic tape while reducing the number of backhitches. A controller detects a pattern of synchronizing events for received data records to be written to tape; writes each transaction of data records to the magnetic; tape; accumulates the synchronized transactions in a buffer; and subsequently recursively writes the accumulated transactions of data records from the buffer to the magnetic tape in a sequence. A single backhitch may be employed to place the recursively written accumulated data records following the preceding data, maximizing performance and capacity.
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Patent Agency Ranking
公开(公告)号：AU2002358766A1
公开(公告)日：2003-07-15
申请号：AU2002358766
申请日：2002-12-19
Applicant: IBM
Inventor： BLAUM MARIO , JAQUETTE GLEN ALAN , MARCUS BRIAN HARRY , MELAS CONSTANTIN MICHAEL
Abstract: Provided is a method, system, and program for providing synchronization in a binary data stream. A binary data stream is received. A synchronization mark having at least one isolated peak is generated into at least one point in the data stream. An encoded data stream is formed by concatenating the synchronization mark with the received binary data. During decoding, the synchronization mark is detected based on error propagation occurring adjacent to the at least one isolated peak of the synchronization mark.
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公开(公告)号：MY114963A
公开(公告)日：2003-02-28
申请号：MYPI9804491
申请日：1998-09-30
Applicant: IBM
Inventor： JAQUETTE GLEN ALAN
Abstract: DISCLOSED ARE A METHOD AND APPARATUS FOR SWITCHING BETWEEN LOSSLESS DATA COMPRESSION MODES (40, 41), AND THE SWITCHING INDICATED BY AT LEAST ONE MULTIBIT MODE SWITCH CHARACTER. THE BINARY FORMAT INPUT DATA IS RECEIVED AND A FIFO DETERMINATION OF THE COMPRESSION EFFICIENCY OF THE INPUT DATA UNDER EACH MODE IS MADE ON AN ONGOING BASIS. THE ONGOING BASIS MAY BE FOR EACH COMPRESSED CODE WORD OR MORE. A FIFO COMPARISON OF THE COMPRESSION EFFICIENCIES UNDER EACH MODE ARE MADE, AND THE MODES FOR COMPRESSING THE INPUT DATA ARE SWITCHED ONLY UPON THE COMPARISON, OR ACCUMULATED COMPARISONS, INDICATING THE COMPRESSION EFFICIENCY OF THE PRESENT MODE IS GREATER THAN THE COMPRESSION EFFICIENCY OF THE OTHER MODE BY A THRESHOLD VALUE (60, 61) THE TRESHOLD VALUE DIRECTLY RELATED TO THE NUMBER OF BITS IN THE MULTIBIT MODE SWITCH CHARACTER. ONE OR BOTH OF THE DATA COMPRESSION MODES MAY COMPRISE A LEMPEL-ZIV COMPRESSION, SUCH AS ALDC (LZ-1 DERIVATIVE) OR DCLZ (LZ-2 DERIVATIVE), FOR COMPRESSING THE INPUT DATA INTO VARIABLE SIZED TOKENS, AND THE FIFO COMPRESSION EFFICIENCY MAY BE DETERMINED BASED ON THE BIT LENGTH FOR EACH VARIABLE SIZED TOKEN.
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公开(公告)号：GB2360678A
公开(公告)日：2001-09-26
申请号：GB0027315
申请日：2000-11-09
Applicant: IBM
Inventor： JAQUETTE GLEN ALAN
Abstract: An adapter and a method for adapting a programmable digital maximum likelihood detector to a variable channel output and a calibration system for calibrating a programmable digital maximum likelihood detector from unknown data in a known code at a variable channel output, the maximum likelihood detector having a number of maximum likelihood states. A detector detects a digital sample of the recorded analog signals as corresponding to one of the maximum likelihood states. An accumulator partially accumulates the detected digital sample with prior detected digital samples corresponding to the one of the maximum likelihood states. Logic coupled to the accumulator employs the accumulated digital samples for the corresponding maximum likelihood state to determine at least one numerical metric coefficient matching the digital samples to the one of the maximum likelihood states, and updates or sets the numerical metric coefficient. Wherein the numerical metric coefficents are applied to the digital samples to generate the metrics used in determining which of the maximum likelihood states the sample corresponding to.
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公开(公告)号：AU4599000A
公开(公告)日：2000-12-12
申请号：AU4599000
申请日：2000-05-18
Applicant: IBM
Inventor： JAQUETTE GLEN ALAN , KOSKI JOHN ALEXANDER , TSURUTA KAZUHIRO
IPC: G11B27/28 , G11B27/10 , G11B27/32 , G11B27/36 , G11B15/087
Abstract: A system and method for precisely registering and synchronizing data sets on a recording media having a prerecorded servo pattern. The recording media is subject to continuing movement for reading and/or writing the data sets, interrupted by stopping at the end of a selected data set and restarting. During the continuing movement of the recording media, a detector coupled to the servo system continuously reads linear position registration data modulated into the prerecorded servo pattern. An interpolator interpolates the prerecorded registration data to provide precision registration information for the data sets. Upon the drive stopping the recording media, then back hitching the media and the movement restarting, selected read and interpolated registration information is provided. The detector again reads and interpolates the prerecorded registration data, and a comparator compares the again read and interpolated registration information to the provided read and interpolated registration information and any predetermined offset, and indicates a comparison match. A data formatter coupled to the comparator, responsive to the comparison match indication, synchronizes the reading and/or writing of data sets on the recording media.
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公开(公告)号：SG70149A1
公开(公告)日：2000-01-25
申请号：SG1999000142
申请日：1999-01-22
Applicant: IBM
Inventor： HUTCHINS ROBERT ALLEN , JAQUETTE GLEN ALAN , TSURUTA KAZUHIRO
Abstract: Disclosed is a digital edge processor frequency control for estimating the center frequency of a recorded signal having a known format, such as data recorded on a CLV optical disk or on magnetic tape. The read channel includes a sampling detector which samples the recorded signal at a known rate to provide edge position signals (PAT) indicating the location of recorded pulse edges. An edge pattern identifier detects whether the edge signals of the recording signal match a predetermined element of the known format. Examples of predetermined elements include a pulse of a known length and whose edges are spaced a known distance, a predetermined pulse pattern, or a pulse or pattern at a known location. An interval counter is coupled to the pattern identifier for measuring the interval length between the edges of the matching pulse or pattern in units of the sample length. A center frequency estimator calculates the period of the center frequency of the matching edges by relating the matching edge interval length to a predetermined nominal wave length for the predetermined element of the known format. The result is a Tau that is used to establish the center frequency for the digital PLL.
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