Patents by Inventor Zachary Keirn

Zachary Keirn has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 8995242
    Abstract: A system and method for adjusting the radial tilt, tangential tilt, or a combination of radial and tangential tilt of an optical detection unit in an optical disc reading system can include applying different weighting factors to different signal components depending on which detection area detects the component, measuring a value of a signal characteristic, such as signal-to-noise ratio, of two signals with different sets of weighting factors, and determining an adjustment factor to the radial tilt as a function of the of the measured signal characteristic values.
    Type: Grant
    Filed: September 18, 2013
    Date of Patent: March 31, 2015
    Assignee: Marvell International Ltd.
    Inventors: Mats Oberg, Zachary Keirn, Christopher Painter
  • Patent number: 8957793
    Abstract: Aspects of the disclosure provide a method. The method includes boosting a portion of frequency components of a digital signal that is converted from an analog signal based on a clock signal, generating a decision signal based on the boosted digital signal, generating a timing error signal based on the boosted digital signal and the decision signal, and filtering the timing error signal to generate a voltage signal to control a voltage controlled oscillator to generate the clock signal.
    Type: Grant
    Filed: September 10, 2012
    Date of Patent: February 17, 2015
    Assignee: Marvell International Ltd.
    Inventors: Jingfeng Liu, Mats Oberg, Zachary Keirn, Bin Ni
  • Patent number: 8830808
    Abstract: Aspects of the disclosure provide a signal processing circuit. The signal processing circuit includes a processing path and a zero-start module. The processing path is configured to process an electrical signal that is generated in response to reading data on a storage medium. The data includes at least a first field and a second field. The electrical signal has a first profile corresponding to the first field and has a second profile corresponding to the second field. The zero-start module is configured to detect a field change from the first field to the second field, and control the processing path to add a compensation as a function of a profile change from the first profile to the second profile to keep the processed electrical signal to have a predetermined profile in response to the detected field change.
    Type: Grant
    Filed: August 16, 2010
    Date of Patent: September 9, 2014
    Assignee: Marvell International Ltd.
    Inventors: Bin Ni, Zachary Keirn, Mats Oberg
  • Patent number: 8755260
    Abstract: Aspects of the disclosure provide an apparatus. The apparatus includes a collimator configured to have a plurality of positions, and a controller configured to control the collimator to move to a predetermined position associated with a data layer of an optical storage medium to collimate a light beam. The collimated light beam is then focused onto the data layer of the optical storage medium.
    Type: Grant
    Filed: June 13, 2012
    Date of Patent: June 17, 2014
    Assignee: Marvell World Trade Ltd.
    Inventors: Mats Oberg, Zachary Keirn
  • Patent number: 8553510
    Abstract: A system and method for adjusting the radial tilt, tangential tilt, or a combination of radial and tangential tilt of an optical detection unit in an optical disc reading system can include applying different weighting factors to different signal components depending on which detection area detects the component, measuring a value of a signal characteristic, such as signal-to-noise ratio, of two signals with different sets of weighting factors, and determining an adjustment factor to the radial tilt as a function of the of the measured signal characteristic values.
    Type: Grant
    Filed: August 9, 2012
    Date of Patent: October 8, 2013
    Assignee: Marvell International Ltd.
    Inventors: Mats Oberg, Zachary Keirn, Christopher Painter
  • Patent number: 8385165
    Abstract: Aspects of the disclosure provide a method for efficiently calibrating an optical recording device. The method can include receiving a first signal corresponding to a wobbled track of a memory medium, phase-locking a second signal to the first signal, the second signal being used to extract embedded information in the wobbled track, and determining an optimum setting of the optical recording device based on a locking quality of the first signal and the second signal.
    Type: Grant
    Filed: January 26, 2012
    Date of Patent: February 26, 2013
    Assignee: Marvell International Ltd.
    Inventors: Jingfeng Liu, Zachary Keirn
  • Publication number: 20130021890
    Abstract: Aspects of the disclosure provide an apparatus. The apparatus includes a collimator configured to have a plurality of positions, and a controller configured to control the collimator to move to a predetermined position associated with a data layer of an optical storage medium to collimate a light beam. The collimated light beam is then focused onto the data layer of the optical storage medium.
    Type: Application
    Filed: June 13, 2012
    Publication date: January 24, 2013
    Inventors: Mats OBERG, Zachary Keirn
  • Patent number: 8274413
    Abstract: A timing loop for generating a channel clock signal for driving an analog to digital converter (ADC) includes a slicer bias loop configured to generate an asymmetry compensation signal for a digital output signal from the ADC, the first adder configured to asymmetrically compensate the digital output signal based on the asymmetry compensation signal from the slicer bias loop, a limit equalizer configured to limit a boost range of the asymmetrically compensated digital output signal from the adder, a slicer configured to generate a temporary decision signal based on the asymmetrically compensated digital output signal from the limit equalizer, a phase detector configured to generate a timing error signal based on the asymmetrically compensated digital output signal from the limit equalizer and the temporary decision signal from the slicer; and the first filter configured to generate a clock signal for driving the ADC based on the time error signal from the phase detector.
    Type: Grant
    Filed: September 8, 2010
    Date of Patent: September 25, 2012
    Assignee: Marvell International Ltd.
    Inventors: Jingfeng Liu, Mats Oberg, Zachary Keirn, Bin Ni
  • Patent number: 8243569
    Abstract: A system and method for adjusting the radial tilt, tangential tilt, or a combination of radial and tangential tilt of an optical detection unit in an optical disc reading system can include applying different weighting factors to different signal components depending on which detection area detects the component, measuring a value of a signal characteristic, such as signal-to-noise ratio, of two signals with different sets of weighting factors, and determining an adjustment factor to the radial tilt as a function of the of the measured signal characteristic values.
    Type: Grant
    Filed: March 22, 2011
    Date of Patent: August 14, 2012
    Assignee: Marvell International Ltd.
    Inventors: Mats Oberg, Zachary Keirn, Christopher Painter
  • Patent number: 8107328
    Abstract: Aspects of the disclosure provide a method for efficiently calibrating an optical recording device. The method can include receiving a first signal corresponding to a wobbled track of a memory medium, phase-locking a second signal to the first signal, the second signal being used to extract embedded information in the wobbled track, and determining an optimum setting of the optical recording device based on a locking quality of the first signal and the second signal.
    Type: Grant
    Filed: October 17, 2008
    Date of Patent: January 31, 2012
    Assignee: Marvell International Ltd.
    Inventors: Jingfeng Liu, Zachary Keirn
  • Patent number: 8046669
    Abstract: Methods and apparatus are provided for measuring the performance of a read channel. A number of detection techniques, such as SOVA and maximum-a-posteriori (MAP) detectors, produce a bit decision and a corresponding reliability value associated with the bit decision. The reliability value associated with the bit decision may be expressed, for example, in the form of log likelihood ratios (LLRs). The reliability value can be monitored and used as a performance measure. The present invention provides a channel performance measure that generally correlates directly to the BER but can be collected in less time.
    Type: Grant
    Filed: January 14, 2011
    Date of Patent: October 25, 2011
    Assignee: Agere Systems Inc.
    Inventors: Nils Graef, Zachary Keirn
  • Patent number: 7969848
    Abstract: A media defect compensation system and method may decouple effects of asymmetry from baseline error compensation computations. In some embodiments, a switching mechanism passes a baseline error signal into a baseline loop when a determination is made that a baseline error signal is not affected by asymmetry, and otherwise freezes the baseline loop when asymmetry may influence baseline error calculations.
    Type: Grant
    Filed: January 22, 2008
    Date of Patent: June 28, 2011
    Assignee: Marvell International Ltd.
    Inventors: Jin Xie, Mats Oberg, Jingfeng Liu, Zachary Keirn
  • Patent number: 7965597
    Abstract: Aspects of the disclosure provide a method for recording. The method includes receiving a tracking signal corresponding to a recording track on a storage medium, phase-locking an internal signal to the tracking signal by reducing a phase error generated based on the internal signal and the tracking signal, generating a phase bias, combining the phase bias into the phase error to phase-shift the internal signal from the tracking signal, and recording on the recording track based on the internal signal.
    Type: Grant
    Filed: July 8, 2010
    Date of Patent: June 21, 2011
    Assignee: Marvell International, Ltd.
    Inventors: Mats Oberg, Zachary Keirn
  • Patent number: 7961124
    Abstract: A device and process to compensate for asymmetrical qualities of an analog input signal, if present, and generate a timing signal. The timing signal is then used for analog to digital conversion.
    Type: Grant
    Filed: April 3, 2009
    Date of Patent: June 14, 2011
    Assignee: Marvell International Ltd.
    Inventors: Jingfeng Liu, Mats Oberg, Zachary Keirn, Bin Ni
  • Publication number: 20110119566
    Abstract: Methods and apparatus are provided for measuring the performance of a read channel. A number of detection techniques, such as SOVA and maximum-a-posteriori (MAP) detectors, produce a bit decision and a corresponding reliability value associated with the bit decision. The reliability value associated with the bit decision may be expressed, for example, in the form of log likelihood ratios (LLRs). The reliability value can be monitored and used as a performance measure. The present invention provides a channel performance measure that generally correlates directly to the BER but can be collected in less time.
    Type: Application
    Filed: January 14, 2011
    Publication date: May 19, 2011
    Applicant: AGERE SYSTEMS INC.
    Inventors: Nils Graef, Zachary Keirn
  • Patent number: 7941732
    Abstract: Methods and apparatus are provided for measuring the performance of a read channel. A number of detection techniques, such as SOVA and maximum-a-posteriori (MAP) detectors, produce a bit decision and a corresponding reliability value associated with the bit decision. The reliability value associated with the bit decision may be expressed, for example, in the form of log likelihood ratios (LLRs). The reliability value can be monitored and used as a performance measure. The present invention provides a channel performance measure that generally correlates directly to the BER but can be collected in less time.
    Type: Grant
    Filed: March 30, 2010
    Date of Patent: May 10, 2011
    Assignee: Agere Systems Inc.
    Inventors: Nils Graef, Zachary Keirn
  • Patent number: 7933181
    Abstract: A system and method for adjusting the radial tilt, tangential tilt, or a combination of radial and tangential tilt of an optical detection unit in an optical disc reading system can include applying different weighting factors to different signal components depending on which detection area detects the component, measuring a value of a signal characteristic, such as signal-to-noise ratio, of two signals with different sets of weighting factors, and determining an adjustment factor to the radial tilt as a function of the of the measured signal characteristic values.
    Type: Grant
    Filed: April 28, 2008
    Date of Patent: April 26, 2011
    Assignee: Marvell International Ltd.
    Inventors: Mats Oberg, Zachary Keirn, Christopher Painter
  • Patent number: 7825836
    Abstract: A timing loop for generating a channel clock signal for driving an analog to digital converter (ADC) includes a slicer bias loop configured to generate an asymmetry compensation signal for a digital output signal from the ADC, the first adder configured to asymmetrically compensate the digital output signal based on the asymmetry compensation signal from the slicer bias loop, a limit equalizer configured to limit a boost range of the asymmetrically compensated digital output signal from the adder, a slicer configured to generate a temporary decision signal based on the asymmetrically compensated digital output signal from the limit equalizer, a phase detector configured to generate a timing error signal based on the asymmetrically compensated digital output signal from the limit equalizer and the temporary decision signal from the slicer; and the first filter configured to generate a clock signal for driving the ADC based on the time error signal from the phase detector.
    Type: Grant
    Filed: January 24, 2008
    Date of Patent: November 2, 2010
    Assignee: Marvell International, Ltd
    Inventors: Jingfeng Liu, Mats Oberg, Zachary Keirn, Bin Ni
  • Patent number: 7817512
    Abstract: The present disclosure can provide a method and an apparatus to correct wobble phase slip in an optical disc recording system during recording. The method of correcting a phase slip can include receiving a wobble signal of a first frequency, sampling the wobble signal to generate a sampled wobble signal, where the wobble signal is sampled at a second frequency that corresponds to a frequency of a sampling signal, comparing a phase of the sampled wobble signal with a phase of a controlled signal to generate a phase error, modifying the phase error by adding a phase bias, and adjusting the second frequency based on the modified phase error to reduce a magnitude of the modified phase error.
    Type: Grant
    Filed: October 26, 2007
    Date of Patent: October 19, 2010
    Assignee: Marvell International, Ltd.
    Inventors: Mats Oberg, Zachary Keirn
  • Publication number: 20100185924
    Abstract: Methods and apparatus are provided for measuring the performance of a read channel. A number of detection techniques, such as SOVA and maximum-a-posteriori (MAP) detectors, produce a bit decision and a corresponding reliability value associated with the bit decision. The reliability value associated with the bit decision may be expressed, for example, in the form of log likelihood ratios (LLRs). The reliability value can be monitored and used as a performance measure. The present invention provides a channel performance measure that generally correlates directly to the BER but can be collected in less time.
    Type: Application
    Filed: March 30, 2010
    Publication date: July 22, 2010
    Applicant: Agere Systems Inc.
    Inventors: Nils Graef, Zachary Keirn