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公开(公告)号：AU2003216844A1
公开(公告)日：2003-10-13
申请号：AU2003216844
申请日：2003-03-14
Applicant: IBM
Inventor： GALBRAITH RICHARD LEO
Abstract: A multi-pole electric pulse generator contains poles having a pseudo-random distribution. Preferably, poles are equally sized and spaced, and polarity corresponds to a pseudo-noise binary sequence, which is specifically a primitive polynomial m-sequence. At one point in the rotor's revolution, all rotor poles are aligned with corresponding stator poles to provide maximum net magnetic flux through the armature windings. At all other rotor positions, the poles are misaligned so that the net flux through the armature windings is small. In operation, rotation through the misaligned rotor positions produces essentially no flux change so that no electric power is generated. When the rotor reaches the aligned position, there is a sudden, large flux change which generates a high-energy electric pulse. The exemplary application is for generating an ignition spark of an internal combustion engine.
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公开(公告)号：GB2286952A
公开(公告)日：1995-08-30
申请号：GB9503986
申请日：1995-02-28
Applicant: IBM
Inventor： COKER JONATHAN DARREL , DOLIVO FRANCOIS BERNARD , GALBRAITH RICHARD LEO , HERMANN RETO , HIRT WALTER , VANNORSDEL KEVIN
IPC: G11B20/10 , G11B20/18 , H03H15/00 , H03H17/00 , H03H21/00 , H03M13/23 , H04B3/04 , H04L25/497 , G11B20/14
Abstract: A method and apparatus are provided for maximum-likelihood data detection in a partial-response (PR) data channel including a head and disk assembly providing an analog signal coupled to an analog to digital converter (ADC) providing digital samples. A plurality of digital samples are received from the ADC. The received digital samples are applied to a selected first filter 402 and a selected second filter 404. The first filtered digital samples are applied to a first data detector 406, and the second filtered digital samples are applied to a second data detector 408. A predetermined parameter is identified 410, and at least one of the first and second data detectors is selected responsive to the identified predetermined parameter. The detectors may comprise partial response, adaptive, full-state or reduced-state Viterbi detectors (e.g. PR4 or EPR4 Viterbi detectors).
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公开(公告)号：DE69023372T2
公开(公告)日：1996-06-20
申请号：DE69023372
申请日：1990-02-21
Applicant: IBM
Inventor： GALBRAITH RICHARD LEO , HEISE NYLES NORBERT
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公开(公告)号：DE69327618D1
公开(公告)日：2000-02-24
申请号：DE69327618
申请日：1993-06-30
Applicant: IBM
Inventor： COKER JONATHAN DARREL , GALBRAITH RICHARD LEO
IPC: G11B5/00 , G11B5/012 , G11B5/09 , G11B5/84 , G11B19/04 , G11B20/10 , G11B20/18 , G11B33/10 , G06F11/00
Abstract: The invention provides a circuit and method for performing test procedures on a data storage and recovery system for a magnetic storage unit. Error sample values from a read operator in a data storage and recovery system are applied to a first and a second process path to generate output signals. A source of level samples of a logical data level is also provided. The first process path generates an output signal comprising the square of each error value sample. The second process path compares the error value samples and a compare level and generates an output signal comprising a result of each comparison. The output signal of the first process path, the second process path, or the level samples is selected and is associated with a data type. In response to a coincidence of a data type associated with the selected signal with a desired data type, the selected signal is gated and then accumulated. The window during which the selected signal is accumulated may vary. The accumulated value is used as an input variable to a selected test to determine the accuracy of the data storage and recovery system.
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5.发明专利
公开(公告)号：SG48468A1
公开(公告)日：1998-04-17
申请号：SG1996010494
申请日：1996-08-26
Applicant: IBM
Inventor： GALBRAITH RICHARD LEO , STANEK DAVID JAMES
Abstract: A method and apparatus are provided for gain adjustment of a signal. A plurality of comparators compare the signal with a plurality of threshold values. An envelope detector coupled to the comparator includes a peak capture function for detecting the amplitude of the signal and a polarity memory for detecting polarity of the signal. A gain control function for setting a gain correction value is responsive to the peak capture function and the polarity memory. Features of the signal gain adjustment method and apparatus of the invention include an intelligent hold of the gain control over both thermal asperities and null gaps in the signal.
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Patent Agency Ranking
公开(公告)号：SG42862A1
公开(公告)日：1997-10-17
申请号：SG1996000246
申请日：1992-05-20
Applicant: IBM
Inventor： COKER JONATHAN DARREL , DOLIVO FRANCOIS BERNARD , GALBRAITH RICHARD LEO , SCHOTT WOLFGANG HANS , ZIPEROVICH PABLO ALEJANDRO
Abstract: A method and apparatus are provided for controlling a digital filter function included in a data path within gain and timing control loops of a PRML magnetic recording channel. The digital filter function is removed from the data path during an acquisition mode and the digital filter function is restored to the data path during a tracking mode. A predetermined gain and a quantized delay at a synchronization frequency are provided when switching from acquisition mode to tracking mode. A unity gain and a delay of an integer number of sample periods are provided at a synchronization frequency when switching from acquisition mode to tracking mode.
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公开(公告)号：DE69023372D1
公开(公告)日：1995-12-14
申请号：DE69023372
申请日：1990-02-21
Applicant: IBM
Inventor： GALBRAITH RICHARD LEO , HEISE NYLES NORBERT
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公开(公告)号：DE60315617T2
公开(公告)日：2008-06-05
申请号：DE60315617
申请日：2003-03-14
Applicant: IBM
Inventor： GALBRAITH RICHARD LEO
Abstract: A multi-pole electric pulse generator contains poles having a pseudo-random distribution. Preferably, poles are equally sized and spaced, and polarity corresponds to a pseudo-noise binary sequence, which is specifically a primitive polynomial m-sequence. At one point in the rotor's revolution, all rotor poles are aligned with corresponding stator poles to provide maximum net magnetic flux through the armature windings. At all other rotor positions, the poles are misaligned so that the net flux through the armature windings is small. In operation, rotation through the misaligned rotor positions produces essentially no flux change so that no electric power is generated. When the rotor reaches the aligned position, there is a sudden, large flux change which generates a high-energy electric pulse. The exemplary application is for generating an ignition spark of an internal combustion engine.
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公开(公告)号：SG72817A1
公开(公告)日：2000-05-23
申请号：SG1998001079
申请日：1998-05-19
Applicant: IBM
Inventor： COKER JONATHAN DARREL , ELEFTHERIOU EVANGELOS STAVROS , GALBRAITH RICHARD LEO , HIRT WALTER
Abstract: A method and apparatus are provided for data detection for a partial-response maximum-likelihood (PRML) data detection channel in a direct access storage device. A class-IV partial response (PR4) signal is applied to a PR4 Viterbi detector to provide a PR4 Viterbi output and is applied to a first matching delay circuit to provide a delayed PR4 signal. The PR4 Viterbi output is subtracted from the delayed PR4 signal and a resulting signal is applied to a first filter having a frequency response of 1/(1- alpha D2). The filtered output signal is applied to a second filter providing a second filtered output signal. The PR4 Viterbi output is applied to a second matching delay circuit to provide a delayed PR4 Viterbi output signal. The delayed PR4 Viterbi output is corrected responsive to the second filtered output signal. The first filter is an infinite impulse response (IIR) filter and the filtered output signal represents whitened noise and modified PRML error events. The second filter is a matched filter used to identify dominant error events.
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公开(公告)号：SG42844A1
公开(公告)日：1997-10-17
申请号：SG1996000072
申请日：1993-06-30
Applicant: IBM
Inventor： COKER JONATHAN DARREL , GALBRAITH RICHARD LEO
IPC: G11B5/00 , G11B5/012 , G11B5/09 , G11B5/84 , G11B19/04 , G11B20/10 , G11B20/18 , G11B33/10 , G06F11/00
Abstract: The invention provides a circuit and method for performing test procedures on a data storage and recovery system for a magnetic storage unit. Error sample values from a read operator in a data storage and recovery system are applied to a first and a second process path to generate output signals. A source of level samples of a logical data level is also provided. The first process path generates an output signal comprising the square of each error value sample. The second process path compares the error value samples and a compare level and generates an output signal comprising a result of each comparison. The output signal of the first process path, the second process path, or the level samples is selected and is associated with a data type. In response to a coincidence of a data type associated with the selected signal with a desired data type, the selected signal is gated and then accumulated. The window during which the selected signal is accumulated may vary. The accumulated value is used as an input variable to a selected test to determine the accuracy of the data storage and recovery system.
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