Patents by Inventor Umang Mehta

Umang Mehta 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: 9305591
    Abstract: A magnetic recording device includes a preprocessor, an interpolator and a slicer. The preprocessor receives at least n saturated input signals including an nth saturated input signal The preprocessor is configured to process each of the n saturated input signals to produce a corresponding nth output signal. The n output signals include an nm output signal from the nth saturated input signal. The interpolator processes the nth output signal to determine an nth interpolator output. The slicer determines an nth slicer output for the nh output signal. The nth slicer output is at one of three different levels. The preprocessor can receive and process an n +1th saturated input signal to produce an n +1th output signal that is based on a difference between the nth interpolator output and the level of the nth slicer output.
    Type: Grant
    Filed: June 20, 2014
    Date of Patent: April 5, 2016
    Assignee: Quantum Corporation
    Inventors: Marc Feller, Jaewook Lee, Umang Mehta
  • Patent number: 9047900
    Abstract: A media drive includes a head, a servo signal processing circuit, an actuator and a processor. The head is positioned near a data storage medium, and includes a servo element. The servo signal processing circuit is coupled to the servo element to output a position error signal. The actuator controls a position of the head relative to the data storage medium. The processor communicates with the actuator and the servo signal processing circuit. The processor provides a filtered position error signal to the actuator to compensate for a position displacement between the head and the data storage medium. The filtered position error signal includes a sum of outputs from a first compensation filter and a second compensation filter that is each applied to the position error signal output. The compensation filters attenuate disturbance frequencies that contribute to the position displacement. Each of the compensation filters has a sampling rate relating to the respective disturbance frequency.
    Type: Grant
    Filed: June 20, 2014
    Date of Patent: June 2, 2015
    Assignee: Quantum Corporation
    Inventors: Turguy Goker, Ming-Chih Weng, Umang Mehta, Ryan Taylor
  • Publication number: 20140355153
    Abstract: An apparatus and method for providing adaptive disturbance compensation with multi-rate synchronized sampling is disclosed herein. The dynamic disturbance occurring in a media drive during read/write operations is attenuated using the adaptive disturbance compensation scheme. A plurality of compensation filters are used, each of the compensation filters configured to attenuate a disturbance caused by a particular source within the media drive. Each of the compensation filters is computed based on a sampling rate relevant to the respective disturbances.
    Type: Application
    Filed: June 20, 2014
    Publication date: December 4, 2014
    Applicant: Quantum Corporation
    Inventors: Turguy GOKER, Ming-chih WENG, Umang MEHTA, Ryan TAYLOR
  • Publication number: 20140300986
    Abstract: In one embodiment, a read channel comprises: a preprocessor for receiving a first signal and producing a second signal from the first signal using current values of a positive coefficient, a zero coefficient, and a negative coefficient; an interpolator for producing a third signal based on the second signal; and a slicer for producing a fourth signal from the third signal by estimating a level for the third signal. The fourth signal is at one of three levels consisting of a positive level, a zero level, and a negative level. For every n first signals received by the preprocessor, the current value of one of the positive coefficient, the zero coefficient, and the negative coefficient is adjusted depending on which of the three levels the fourth signal is at.
    Type: Application
    Filed: June 20, 2014
    Publication date: October 9, 2014
    Applicant: Quantum Corporation
    Inventors: Marc FELLER, Jaewook LEE, Umang MEHTA
  • Patent number: 8773800
    Abstract: An apparatus and method for providing adaptive disturbance compensation with multi-rate synchronized sampling is disclosed herein. The dynamic disturbance occurring in a media drive during read/write operations is attenuated using the adaptive disturbance compensation scheme. A plurality of compensation filters are used, each of the compensation filters configured to attenuate a disturbance caused by a particular source within the media drive. Each of the compensation filters is computed based on a sampling rate relevant to the respective disturbances.
    Type: Grant
    Filed: October 8, 2010
    Date of Patent: July 8, 2014
    Assignee: Quantum Corporation
    Inventors: Turguy Goker, Ming-chih Weng, Umang Mehta, Ryan Taylor
  • Patent number: 8760789
    Abstract: In one embodiment, a read channel comprises: a preprocessor for receiving a first signal and producing a second signal from the first signal using current values of a positive coefficient, a zero coefficient, and a negative coefficient; an interpolator for producing a third signal based on the second signal; and a slicer for producing a fourth signal from the third signal by estimating a level for the third signal. The fourth signal is at one of three levels consisting of a positive level, a zero level, and a negative level. For every n first signals received by the preprocessor, the current value of one of the positive coefficient, the zero coefficient, and the negative coefficient is adjusted depending on which of the three levels the fourth signal is at.
    Type: Grant
    Filed: September 22, 2011
    Date of Patent: June 24, 2014
    Assignee: Quantum Corporation
    Inventors: Marc Feller, Jaewook Lee, Umang Mehta
  • Patent number: 8594254
    Abstract: In one embodiment, an interpolator-based timing recovery system improves accuracy by calculating additional sampled signals of a digital signal and generating an interpolation based on the additional sampled signals and the digital signal, while employing a parallel architecture to maintain system clock frequency and a pipeline architecture to minimize sampled data memory requirement.
    Type: Grant
    Filed: September 27, 2010
    Date of Patent: November 26, 2013
    Assignee: Quantum Corporation
    Inventors: Jaewook Lee, Umang Mehta, Jerry Hodges
  • Publication number: 20130077187
    Abstract: In one embodiment, a read channel comprises: a preprocessor for receiving a first signal and producing a second signal from the first signal using current values of a positive coefficient, a zero coefficient, and a negative coefficient; an interpolator for producing a third signal based on the second signal; and a slicer for producing a fourth signal from the third signal by estimating a level for the third signal. The fourth signal is at one of three levels consisting of a positive level, a zero level, and a negative level. For every n first signals received by the preprocessor, the current value of one of the positive coefficient, the zero coefficient, and the negative coefficient is adjusted depending on which of the three levels the fourth signal is at.
    Type: Application
    Filed: September 22, 2011
    Publication date: March 28, 2013
    Applicant: QUANTUM CORPORATION
    Inventors: Marc Feller, Jaewook Lee, Umang Mehta
  • Publication number: 20120087031
    Abstract: An apparatus and method for providing adaptive disturbance compensation with multi-rate synchronized sampling is disclosed herein. The dynamic disturbance occurring in a media drive during read/write operations is attenuated using the adaptive disturbance compensation scheme. A plurality of compensation filters are used, each of the compensation filters configured to attenuate a disturbance caused by a particular source within the media drive. Each of the compensation filters is computed based on a sampling rate relevant to the respective disturbances.
    Type: Application
    Filed: October 8, 2010
    Publication date: April 12, 2012
    Applicant: Quantum Corporation
    Inventors: Turguy Goker, Ming-chih Weng, Umang Mehta, Ryan Taylor
  • Publication number: 20120076244
    Abstract: In one embodiment, an interpolator-based timing recovery system improves accuracy by calculating additional sampled signals of a digital signal and generating an interpolation based on the additional sampled signals and the digital signal, while employing a parallel architecture to maintain system clock frequency and a pipeline architecture to minimize sampled data memory requirement.
    Type: Application
    Filed: September 27, 2010
    Publication date: March 29, 2012
    Applicant: QUANTUM CORPORATION
    Inventors: Jaewook LEE, Umang MEHTA, Jerry HODGES
  • Publication number: 20110032630
    Abstract: A circuit for a high-density data recording channel includes a first data detector, a second data detector, one or more multiplexers and a sequence identifier. The first data detector generates a first data detector output, and the second data detector generates a second data detector output. The multiplexers change between a first mode and a second mode to alternately receive the first data detector output and the second data detector output. The sequence identifier receives a data sequence including at least one of a first data sequence, such as VFO data, and a second data sequence, such as random data. The second data sequence includes a greater number of signal levels than the first data sequence. The sequence identifier changes the multiplexers between the first mode and the second mode based on whether the data sequence is the first data sequence or the second data sequence. The data sequence includes a plurality of timing stages.
    Type: Application
    Filed: August 5, 2009
    Publication date: February 10, 2011
    Inventors: Jaewook Lee, Sizhen Yang, Umang Mehta, Jerry Hodges, Marc Feller, Turguy Goker
  • Patent number: 7684144
    Abstract: In a method of multi-rate tracking with a multi-actuator servo control, a track position error is sampled at an asynchronous sample rate for operating a first actuator. The track position error is also sampled at a synchronous sample rate for operating a second actuator. The sampling from the synchronous sample rate is utilized to reduce a delay associated with the sampling at the asynchronous sample rate.
    Type: Grant
    Filed: October 29, 2008
    Date of Patent: March 23, 2010
    Assignee: Quantum Corporation
    Inventors: Turguy Goker, Ming-Chih Weng, Ryan Taylor, Umang Mehta
  • Publication number: 20090222232
    Abstract: Methods, apparatuses and systems directed to calculation of a reel motor torque constant (“KT”). In one implementation, calibration logic energizes supply and take-up reel motors to wind tape from a supply reel to a take-up reel. The calibration logic, during winding, selectively disengages the supply reel motor and measures one or more attributes of the supply reel motor, such as the resulting voltage observed at the winding terminals of the supply reel motor and the angular velocity of the supply reel motor during the period of disengagement. The calibration logic then calculates KT based on the observed attributes.
    Type: Application
    Filed: October 14, 2008
    Publication date: September 3, 2009
    Applicants: Quantum Corporation
    Inventors: Kempton Redhead, Yoshitomi Koike, John Sverida, Umang Mehta, Junichi Hyogo
  • Patent number: 7274528
    Abstract: A method and apparatus is provided to protect head elements on a head of a head guide assembly, having a magnetic tape, and a leader coupled to the magnetic tape at a first end, such that the height of the leader is less than the height of the magnetic tape.
    Type: Grant
    Filed: March 17, 2005
    Date of Patent: September 25, 2007
    Assignee: Certance LLC
    Inventors: John Anthony Hamming, Robert Ralph Heinze, Umang Mehta
  • Publication number: 20060209447
    Abstract: A method and apparatus is provided to protect head elements on a head of a head guide assembly, having a magnetic tape, and a leader coupled to the magnetic tape at a first end, such that the height of the leader is less than the height of the magnetic tape.
    Type: Application
    Filed: March 17, 2005
    Publication date: September 21, 2006
    Inventors: John Hamming, Robert Heinze, Umang Mehta