Patents by Inventor Jihong Ren

Jihong Ren 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: 9584306
    Abstract: An embodiment of the invention relates to a method of phase detection in a receiver circuit with decision feedback equalization. Partial-equalization and full-equalization edge signals are generated. The feedback from the first tap of the decision feedback equalizer is separated from the feedback of the remaining plurality of taps. The feedback from the plurality of taps (not including the first tap) is used to generate partial-equalization edge signals, while the feedback from all the taps is used to generate full-equalization edge signals. The partial-equalization and full-equalization edge signals are utilized by phase-detection circuitry to provide highly-accurate data sampling locations for improved performance.
    Type: Grant
    Filed: June 18, 2015
    Date of Patent: February 28, 2017
    Assignee: Altera Corporation
    Inventors: Wenyi Jin, Jihong Ren, Hae-Chang Lee
  • Publication number: 20170054576
    Abstract: A receiver is equipped with an adaptive phase-offset controller and associated timing-calibration circuitry that together shift the timing for a data sampler and a digital equalizer. The sample and equalizer timing is shifted to a position with less residual inter-symbol interference (ISI) energy relative to the current symbol. The shifted position may be calculated using a measure of signal quality, such as a receiver bit-error rate or a comparison of filter-tap values, to optimize the timing of data recovery.
    Type: Application
    Filed: September 8, 2016
    Publication date: February 23, 2017
    Inventors: Qi Lin, Brian Leibowitz, Hae-Chang Lee, Jihong Ren, Kyung Suk Oh, Jared L. Zerbe
  • Publication number: 20170054577
    Abstract: A transceiver architecture supports high-speed communication over a signal lane that extends between a high-performance integrated circuit (IC) and one or more relatively low-performance ICs employing less sophisticated transmitters and receivers. The architecture compensates for performance asymmetry between ICs communicating over a bidirectional lane by instantiating relatively complex transmit and receive equalization circuitry on the higher-performance side of the lane. Both the transmit and receive equalization filter coefficients in the higher-performance IC may be adaptively updated based upon the signal response at the receiver of the higher-performance IC.
    Type: Application
    Filed: August 10, 2016
    Publication date: February 23, 2017
    Inventors: Jared L. Zerbe, Fariborz Assaderaghi, Brian S. Leibowitz, Hae-Chang Lee, Jihong Ren, Qi Lin
  • Patent number: 9577816
    Abstract: This disclosure provides a clock recovery circuit for a multi-lane communication system. Local clocks are recovered from the input signals using respective local CDR circuits, and associated CDR error signals are aggregated or otherwise combined. A global recovered clock for shared use by the local CDR circuits is generated at a controllable oscillation frequency as a function of a combination of the error signals from the plurality of receivers. A voltage- or current-controlled delay line can also be used to phase adjust the global recovered clock to mitigate band-limited, lane-correlated, high frequency jitter.
    Type: Grant
    Filed: March 13, 2012
    Date of Patent: February 21, 2017
    Assignee: Rambus Inc.
    Inventors: Masum Hossain, Brian Leibowitz, Jihong Ren
  • Publication number: 20160373241
    Abstract: An embodiment of the invention relates to a method of phase detection in a receiver circuit with decision feedback equalization. Partial-equalization and full-equalization edge signals are generated. The feedback from the first tap of the decision feedback equalizer is separated from the feedback of the remaining plurality of taps. The feedback from the plurality of taps (not including the first tap) is used to generate partial-equalization edge signals, while the feedback from all the taps is used to generate full-equalization edge signals. The partial-equalization and full-equalization edge signals are utilized by phase-detection circuitry to provide highly-accurate data sampling locations for improved performance.
    Type: Application
    Filed: June 18, 2015
    Publication date: December 22, 2016
    Applicant: ALTERA CORPORATION
    Inventors: Wenyi JIN, Jihong REN, Hae-Chang LEE
  • Publication number: 20160373277
    Abstract: A method is disclosed. The method includes sampling a data signal having a voltage value at an expected edge time of the data signal. A first alpha value is generated, and a second alpha value generated in dependence upon the voltage value. The data signal is adjusted the first alpha value to derive a first adjusted signal. The data signal is adjusted by the second alpha value to derive a second adjusted signal. The first adjusted signal is sampled to output a first data value while the second adjusted signal is sampled to output a second data value. A selection is made between the first data value and the second data value as a function of a prior received data value to determine a received data value.
    Type: Application
    Filed: June 9, 2016
    Publication date: December 22, 2016
    Inventors: Brian S. Leibowitz, Hae-Chang Lee, Jihong Ren, Ruwan Ratnayake
  • Patent number: 9455825
    Abstract: A receiver is equipped with an adaptive phase-offset controller and associated timing-calibration circuitry that together shift the timing for a data sampler and a digital equalizer. The sample and equalizer timing is shifted to a position with less residual inter-symbol interference (ISI) energy relative to the current symbol. The shifted position may be calculated using a measure of signal quality, such as a receiver bit-error rate or a comparison of filter-tap values, to optimize the timing of data recovery.
    Type: Grant
    Filed: September 29, 2015
    Date of Patent: September 27, 2016
    Assignee: Rambus Inc.
    Inventors: Qi Lin, Brian Leibowitz, Hae-Chang Lee, Jihong Ren, Kyung Suk Oh, Jared L. Zerbe
  • Patent number: 9425997
    Abstract: A transceiver architecture supports high-speed communication over a signal lane that extends between a high-performance integrated circuit (IC) and one or more relatively low-performance ICs employing less sophisticated transmitters and receivers. The architecture compensates for performance asymmetry between ICs communicating over a bidirectional lane by instantiating relatively complex transmit and receive equalization circuitry on the higher-performance side of the lane. Both the transmit and receive equalization filter coefficients in the higher-performance IC may be adaptively updated based upon the signal response at the receiver of the higher-performance IC.
    Type: Grant
    Filed: June 9, 2015
    Date of Patent: August 23, 2016
    Assignee: Rambus Inc.
    Inventors: Jared L. Zerbe, Fariborz Assaderaghi, Brian S. Leibowitz, Hae-Chang Lee, Jihong Ren, Qi Lin
  • Patent number: 9397823
    Abstract: A communication system includes a continuous-time linear equalizer in the clock forward path. The equalizer may be adjusted to minimize clock jitter, including jitter associated with the first few clock edges after the clock signal is enabled. Reducing early-edge jitter reduces the power and circuit complexity otherwise needed to turn the system on quickly.
    Type: Grant
    Filed: October 20, 2014
    Date of Patent: July 19, 2016
    Assignee: Rambus Inc.
    Inventors: Jared Zerbe, Teva Stone, Jihong Ren
  • Patent number: 9391816
    Abstract: A method is disclosed. The method includes sampling a data signal having a voltage value at an expected edge time of the data signal. A first alpha value is generated, and a second alpha value generated in dependence upon the voltage value. The data signal is adjusted by the first alpha value to derive a first adjusted signal. The data signal is adjusted by the second alpha value to derive a second adjusted signal. The first adjusted signal is sampled to output a first data value while the second adjusted signal is sampled to output a second data value. A selection is made between the first data value and the second data value as a function of a prior received data value to determine a received data value.
    Type: Grant
    Filed: August 19, 2014
    Date of Patent: July 12, 2016
    Assignee: Rambus Inc.
    Inventors: Brian S. Leibowitz, Hae-Chang Lee, Jihong Ren, Ruwan Ratnayake
  • Publication number: 20160142200
    Abstract: A receiver is equipped with an adaptive phase-offset controller and associated timing-calibration circuitry that together shift the timing for a data sampler and a digital equalizer. The sample and equalizer timing is shifted to a position with less residual inter-symbol interference (ISI) energy relative to the current symbol. The shifted position may be calculated using a measure of signal quality, such as a receiver bit-error rate or a comparison of filter-tap values, to optimize the timing of data recovery.
    Type: Application
    Filed: September 29, 2015
    Publication date: May 19, 2016
    Inventors: Qi Lin, Brian Leibowitz, Hae-Chang Lee, Jihong Ren, Kyung Suk Oh, Jared L. Zerbe
  • Patent number: 9285457
    Abstract: An electronic device for wirelessly tracking the position of a second electronic device is disclosed. The electronic device includes transceiver circuitry and processing circuitry. The transceiver circuitry includes a beacon generator to generate a beacon at a particular frequency and direction. An antenna array transmits the beacon, and receives at least one modulated reflected beacon from the second electronic device. The transceiver circuitry also includes a discriminator to discriminate between received modulated reflected beacons and received reflected interfering beacons. The processing circuitry couples to the transceiver circuitry and tracks the position of the second device based on the modulated reflected beacons.
    Type: Grant
    Filed: December 26, 2012
    Date of Patent: March 15, 2016
    Assignee: Lattice Semiconductor Corporation
    Inventors: Farshid Aryanfar, Jihong Ren
  • Patent number: 9287616
    Abstract: The disclosed embodiments relate to a technique for calibrating a retro-directive array. During the calibration process, the system measures a gain g1 through a first pair of antennas in the retro-directive array. Next, the system measures a gain g2 through a second pair of antennas in the retro-directive array. The system then simultaneously measures a combined gain G1,2 through the first and second pairs of antennas in the retro-directive array. If G1,2 is less than g1+g2 by more than a threshold value, the system calibrates a phase relationship between the first and second pairs of antennas.
    Type: Grant
    Filed: July 20, 2012
    Date of Patent: March 15, 2016
    Assignee: Lattice Semiconductor Corporation
    Inventors: Farshid Aryanfar, Jihong Ren
  • Publication number: 20150349986
    Abstract: A transceiver architecture supports high-speed communication over a signal lane that extends between a high-performance integrated circuit (IC) and one or more relatively low-performance ICs employing less sophisticated transmitters and receivers. The architecture compensates for performance asymmetry between ICs communicating over a bidirectional lane by instantiating relatively complex transmit and receive equalization circuitry on the higher-performance side of the lane. Both the transmit and receive equalization filter coefficients in the higher-performance IC may be adaptively updated based upon the signal response at the receiver of the higher-performance IC.
    Type: Application
    Filed: June 9, 2015
    Publication date: December 3, 2015
    Inventors: Jared L. Zerbe, Fariborz Assaderaghi, Brian S. Leibowitz, Hae-Chang Lee, Jihong Ren, Qi Lin
  • Patent number: 9178688
    Abstract: A receiver is equipped with an adaptive phase-offset controller and associated timing-calibration circuitry that together shift the timing for a data sampler and a digital equalizer. The sample and equalizer timing is shifted to a position with less residual inter-symbol interference (ISI) energy relative to the current symbol. The shifted position may be calculated using a measure of signal quality, such as a receiver bit-error rate or a comparison of filter-tap values, to optimize the timing of data recovery.
    Type: Grant
    Filed: August 29, 2013
    Date of Patent: November 3, 2015
    Assignee: Rambus Inc.
    Inventors: Qi Lin, Brian Leibowitz, Hae-Chang Lee, Jihong Ren, Kyung Suk Oh, Jared L. Zerbe
  • Patent number: 9077575
    Abstract: A transceiver architecture supports high-speed communication over a signal lane that extends between a high-performance integrated circuit (IC) and one or more relatively low-performance ICs employing less sophisticated transmitters and receivers. The architecture compensates for performance asymmetry between ICs communicating over a bidirectional lane by instantiating relatively complex transmit and receive equalization circuitry on the higher-performance side of the lane. Both the transmit and receive equalization filter coefficients in the higher-performance IC may be adaptively updated based upon the signal response at the receiver of the higher-performance IC.
    Type: Grant
    Filed: June 6, 2013
    Date of Patent: July 7, 2015
    Assignee: Rambus Inc.
    Inventors: Jared L. Zerbe, Fariborz Assaderaghi, Brian S. Leibowitz, Hae-Chang Lee, Jihong Ren, Qi Lin
  • Publication number: 20150078495
    Abstract: This disclosure provides a clock recovery circuit for a multi-lane communication system. Local clocks are recovered from the input signals using respective local CDR circuits, and associated CDR error signals are aggregated or otherwise combined. A global recovered clock for shared use by the local CDR circuits is generated at a controllable oscillation frequency as a function of a combination of the error signals from the plurality of receivers. A voltage- or current-controlled delay line can also be used to phase adjust the global recovered clock to mitigate band-limited, lane-correlated, high frequency jitter.
    Type: Application
    Filed: March 13, 2012
    Publication date: March 19, 2015
    Applicant: Rambus Inc.
    Inventors: Masum Hossain, Brian Leibowitz, Jihong Ren
  • Publication number: 20150049798
    Abstract: A receiver integrated circuit is disclosed that includes a filter and a linear equalization circuit. The filter has an input to receive a signal symbols a main tap and a pre-cursor tap to reduces a pre-cursor ISI acting on the data symbols. The linear equalization circuit couples to the output and cooperates with the filter to further reduce ISI.
    Type: Application
    Filed: November 30, 2012
    Publication date: February 19, 2015
    Applicant: RAMBUS INC.
    Inventors: Masum Hossein, Farshid Aryanfar, Jihong Ren, Jared L. Zerbe
  • Publication number: 20150036732
    Abstract: A method is disclosed. The method includes sampling a data signal having a voltage value at an expected edge time of the data signal. A first alpha value is generated, and a second alpha value generated in dependence upon the voltage value. The data signal is adjusted by the first alpha value to derive a first adjusted signal. The data signal is adjusted by the second alpha value to derive a second adjusted signal. The first adjusted signal is sampled to output a first data value while the second adjusted signal is sampled to output a second data value. A selection is made between the first data value and the second data value as a function of a prior received data value to determine a received data value.
    Type: Application
    Filed: August 19, 2014
    Publication date: February 5, 2015
    Inventors: Brian S. Leibowitz, Hae-Chang Lee, Jihong Ren, Ruwan Ratnayake
  • Publication number: 20150036775
    Abstract: A communication system includes a continuous-time linear equalizer in the clock forward path. The equalizer may be adjusted to minimize clock jitter, including jitter associated with the first few clock edges after the clock signal is enabled. Reducing early-edge jitter reduces the power and circuit complexity otherwise needed to turn the system on quickly.
    Type: Application
    Filed: October 20, 2014
    Publication date: February 5, 2015
    Inventors: Jared Zerbe, Teva Stone, Jihong Ren