Patents by Inventor Li Du

Li Du 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: 8046666
    Abstract: A method of double detection in a perpendicular magnetic read channel is disclosed. The method generally includes the steps of (A) generating an intermediate signal by performing a first detection on an input signal of the perpendicular read channel, the first detection having a first error rate, (B) generating a statistics signal based on the intermediate signal, the statistics signal conveying noise statistics that depend on data in the input signal and (C) generating an output signal by performing a second detection on the input signal using the noise statistics to reduce a second error rate of the second detection compared with the first error rate, wherein the first detection is independent of the second detection.
    Type: Grant
    Filed: August 8, 2007
    Date of Patent: October 25, 2011
    Assignee: LSI Corporation
    Inventors: Jongseung Park, Andrei E. Vityaev, Li Du
  • Patent number: 7963027
    Abstract: A manufacturing method of a switch device having changeable distances involves uniformly arranging more than two throws on the same circumference and then fixing the throws onto corresponding circular carriers. Included further is fixing a number of throws on the inner cylinder surface of a flat cylinder plate body, and fixing the poles in cylinder shape on to the top of the carrier in a cap shape which can be worn on the tip of a single finger. One end of the lead wires is connected to respective throws and pole, the other end is connected to the pin of the interface of the controlled object by fixing or inserting in order to form the switch device. Distances between the throws and the poles are variable.
    Type: Grant
    Filed: January 5, 2004
    Date of Patent: June 21, 2011
    Inventor: Li Du
  • Patent number: 7929240
    Abstract: Various embodiments of the present invention provide systems and methods for reducing head distortion. For example, various embodiments of the present invention provide storage devices that include a storage medium, a read/write head assembly, and an adaptive distortion modification circuit. The storage medium includes information that may be sensed by the read/write head assembly that is disposed in relation to the storage medium. The adaptive distortion modification circuit receives the information sensed by the read/write head assembly and adaptively estimates and implements a distortion compensation factor in the analog domain. In some instances of the aforementioned embodiments, the read/write head assembly includes a magneto resistive head. In such instances, the distortion compensation factor is designed to compensate for non-linear distortion introduced by the magneto resistive head.
    Type: Grant
    Filed: December 18, 2008
    Date of Patent: April 19, 2011
    Assignee: LSI Corporation
    Inventors: George Mathew, Yuan Xing Lee, Harley Burger, Li Du
  • Publication number: 20100287068
    Abstract: The disclosed online transaction method and system uses payment platform acting as an intermediary agent between the merchant and the shipping company to handle the payment. While the payment platform receives payment from the shipping company, the merchant receives payment from the payment platform. The method and system do not require buyers to use the payment method provided by an intermediary transaction platform to make a payment. Instead, the buyer may pay directly to the shipping company. Unlike conventional transaction method based on COD, however, the disclosed online transaction method and system centrally manage a logistics platform or multiple logistics operations run by logistics companies. The merchant does not receive the payment from the logistics company, but rather receive the payment from a centralized payment platform to ensure secure and fast payment.
    Type: Application
    Filed: August 20, 2009
    Publication date: November 11, 2010
    Applicant: Alibaba Group Holding Limited
    Inventors: Xiaoming Hu, Jun Li Du, Xingjun Ni, Xiaoning Qi, Feng Yu, Liang Zhang, Shi Yu Zhu
  • Publication number: 20100157464
    Abstract: Various embodiments of the present invention provide systems and methods for reducing head distortion. For example, various embodiments of the present invention provide storage devices that include a storage medium, a read/write head assembly, and an adaptive distortion modification circuit. The storage medium includes information that may be sensed by the read/write head assembly that is disposed in relation to the storage medium. The adaptive distortion modification circuit receives the information sensed by the read/write head assembly and adaptively estimates and implements a distortion compensation factor in the analog domain. In some instances of the aforementioned embodiments, the read/write head assembly includes a magneto resistive head. In such instances, the distortion compensation factor is designed to compensate for non-linear distortion introduced by the magneto resistive head.
    Type: Application
    Filed: December 18, 2008
    Publication date: June 24, 2010
    Inventors: George Mathew, Yuan Xing Lee, Harley Burger, Li Du
  • Publication number: 20100109686
    Abstract: An apparatus and a method for detection of wear particles in a lubricant are disclosed. The apparatus includes a microfluidic device including a microchannel sized for a lubricant containing wear particles to pass therethrough and first and second electrodes extending into the microchannel. A detection system is coupled with the electrodes for detection of wear particles passing through the microchannel, based on a change in capacitance of the electrodes.
    Type: Application
    Filed: October 30, 2009
    Publication date: May 6, 2010
    Applicant: The University of Akron
    Inventors: Jiang Zhe, Li Du, Joan E. Carletta, Robert J. Veillette
  • Publication number: 20090044084
    Abstract: A method of double detection in a perpendicular magnetic read channel is disclosed. The method generally includes the steps of (A) generating an intermediate signal by performing a first detection on an input signal of the perpendicular read channel, the first detection having a first error rate, (B) generating a statistics signal based on the intermediate signal, the statistics signal conveying noise statistics that depend on data in the input signal and (C) generating an output signal by performing a second detection on the input signal using the noise statistics to reduce a second error rate of the second detection compared with the first error rate, wherein the first detection is independent of the second detection.
    Type: Application
    Filed: August 8, 2007
    Publication date: February 12, 2009
    Inventors: Jongseung Park, Andrei E. Vityaev, Li Du
  • Publication number: 20070008290
    Abstract: The present invention relates to a switch, and a signal generating switch device which can provide continuous real-time response. The problem to be resolved is to provide a method in order to realize a switch device which permits the pole is in a dynamic state in which the pole can change the interval and direction relative to the throw before ad after it contacts the throw during the continuous operation period. The manufacturing method is as follows: firstly, several throws are uniformly provided on an inner concave of a throw carrier in a plate shape and ensured to be on the same circumference. Second, a pole in a pin shape is fixed on the top of a pole carrier in a cap shape which can cover the top part of a finger and ensured to be vertical to the top face of the cap. Finally, the wires with required length are made corresponding to the number of the pole and the throws.
    Type: Application
    Filed: June 30, 2006
    Publication date: January 11, 2007
    Inventor: Li Du
  • Patent number: 6819514
    Abstract: A sampled amplitude read channel for magnetic disk recording which asynchronously samples the analog read signal, adaptively equalizes the resulting discrete time sample values according to a target partial response, extracts synchronous sample values through interpolated timing recovery, and detects digital data from the synchronous sample values using a Viterbi sequence detector is disclosed. To minimize interference from the timing and gain control loops, the phase and magnitude response of the adaptive equalizer filter are constrained at a predetermined frequency using an optimal orthogonal projection operation as a modification to a least mean square (LMS) adaptation algorithm. Further, with interpolated timing recovery, the equalizer filter and its associated latency are removed from the timing recovery loop, thereby allowing a higher order discrete time filter and a lower order analog filter.
    Type: Grant
    Filed: April 30, 1996
    Date of Patent: November 16, 2004
    Assignee: Cirrus Logic, Inc.
    Inventors: Richard T. Behrens, Li Du, William G. Bliss, David E. Reed, Mark S. Spurbeck
  • Patent number: 6490110
    Abstract: Servo circuitry is disclosed that is configured to operate with a magnetic disk drive system. The servo circuitry is comprised of a first servo detector system, a second servo detector system, and a comparator. The first servo detector system and the second servo detector system each receive samples, taken from a read signal, that include servo data. The first servo detector system compares the samples to a plurality of servo codes to generate a first selected code. The second servo detector system compares a first shifted version of the samples to the plurality of servo codes to generate a second selected code. The comparator receives the selected codes and selects one of the selected codes. The selected code represents the servo data. The servo circuitry could also include a third servo detector system that operates on a second shifted version of the samples.
    Type: Grant
    Filed: December 19, 2000
    Date of Patent: December 3, 2002
    Assignee: Cirrus Logic, Inc.
    Inventors: David E. Reed, Stephen A. Turk, Li Du
  • Publication number: 20020114100
    Abstract: Servo circuitry is disclosed that is configured to operate with a magnetic disk drive system. The servo circuitry is comprised of a first servo detector system, a second servo detector system, and a comparator. The first servo detector system and the second servo detector system each receive samples, taken from a read signal, that include servo data. The first servo detector system compares the samples to a plurality of servo codes to generate a first selected code. The second servo detector system compares a first shifted version of the samples to the plurality of servo codes to generate a second selected code. The comparator receives the selected codes and selects one of the selected codes. The selected code represents the servo data. The servo circuitry could also include a third servo detector system that operates on a second shifted version of the samples.
    Type: Application
    Filed: December 19, 2000
    Publication date: August 22, 2002
    Inventors: David E. Reed, Stephen A. Turk, Li Du
  • Publication number: 20020069379
    Abstract: Servo circuitry is disclosed that is configured to operate with a magnetic disk drive system. The servo circuitry is comprised of a first servo detector system, a second servo detector system, and a comparator. The first servo detector system and the second servo detector system each receive samples, taken from a read signal, that include servo data. The first servo detector system compares the samples to a plurality of servo codes to generate a first selected code. The second servo detector system compares a first shifted version of the samples to the plurality of servo codes to generate a second selected code. The comparator receives the selected codes and selects one of the selected codes. The selected code represents the servo data. The servo circuitry could also include a third servo detector system that operates on a second shifted version of the samples.
    Type: Application
    Filed: December 5, 2000
    Publication date: June 6, 2002
    Applicant: Cirrus Logic, Inc.
    Inventors: David E. Reed, Stephen A. Turk, Li Du
  • Patent number: 6381085
    Abstract: The invention includes disk drive circuitry, systems, and methods. The disk drive system comprises control circuitry and a disk device. The disk device stores data and transfers an analog signal representing the data. The control circuitry receives the analog signal, converts the analog signal into a digital signal, and transfers the digital signal. The control circuitry includes zero forcing circuitry and an adaptive filter. The zero forcing circuitry produces new coefficients for the adaptive filter. The control circuitry may also include an analog-to-digital converter, detector, decoder, and LMS circuitry. The analog-to-digital converter receives and samples the analog signal to generate a sampled signal. The adaptive filter shapes the sampled signal based on coefficients to produce an equalized signal. The detector detects binary data from the equalized signal, and the decoder decodes the binary data to generate the digital signal.
    Type: Grant
    Filed: July 12, 1999
    Date of Patent: April 30, 2002
    Assignee: Cirrus Logic, Inc.
    Inventors: Li Du, Mark Stephen Spurbeck, German Feyh
  • Patent number: 6307694
    Abstract: The invention includes disk drive circuitry, systems, and methods. The disk drive system comprises control circuitry and a disk device. The disk device stores data and transfers an analog signal representing the data. The control circuitry receives the analog signal, converts the analog signal into a digital signal, transfers the digital signal, and biases an error signal. The control circuitry includes an analog-to-digital converter, adaptive filter, a decoder, and error signal circuitry. The analog-to-digital converter receives and samples the analog signal to generate a sampled signal. The adaptive filter shapes the sampled signal based on coefficients to produce a shaped signal. The decoder decodes the shaped signal to generate the digital signal. The error signal circuitry generates the biased error signal to adjust the coefficients in the adaptive filter.
    Type: Grant
    Filed: February 24, 1999
    Date of Patent: October 23, 2001
    Assignee: Cirrus Logic, Inc.
    Inventors: Li Du, Mark Stephen Spurbeck, Richard Travis Behrens
  • Patent number: 6208481
    Abstract: A sampled amplitude read channel for magnetic disk recording which asynchronously samples the analog read signal, adaptively equalizes the resulting discrete time sample values according to a target partial response, extracts synchronous sample values through interpolated timing recovery, and detects digital data from the synchronous sample values using a Viterbi sequence detector is disclosed. To minimize interference from the timing and gain control loops, the phase and magnitude response of the adaptive equalizer filter are constrained at a predetermined frequency using an optimal orthogonal projection operation as a modification to a least mean square (LMS) adaptation algorithm. Further, with interpolated timing recovery, the equalizer filter and its associated latency are removed from the timing recovery loop, thereby allowing a higher order discrete time filter and a lower order analog filter.
    Type: Grant
    Filed: June 28, 1999
    Date of Patent: March 27, 2001
    Assignee: Cirrus Logic, Inc.
    Inventors: Mark S. Spurbeck, Li Du, Trent O. Dudley, William G. Bliss, German S. Feyh, Richard T. Behrens
  • Patent number: 5999355
    Abstract: A sampled amplitude read channel for magnetic disk recording which asynchronously samples the analog read signal, adaptively equalizes the resulting discrete time sample values according to a target partial response, extracts synchronous sample values through interpolated timing recovery, and detects digital data from the synchronous sample values using a Viterbi sequence detector is disclosed. To minimize interference from the timing and gain control loops, the phase and magnitude response of the adaptive equalizer filter are constrained at a predetermined frequency using an optimal orthogonal projection operation as a modification to a least mean square (LMS) adaptation algorithm. Further, with interpolated timing recovery, the equalizer filter and its associated latency are removed from the timing recovery loop, thereby allowing a higher order discrete time filter and a lower order analog filter.
    Type: Grant
    Filed: April 30, 1996
    Date of Patent: December 7, 1999
    Assignee: Cirrus Logic, Inc.
    Inventors: Richard T. Behrens, William G. Bliss, Li Du, Mark S. Spurbeck, German S. Feyh, Trent O. Dudley