Patents by Inventor Liangge Xu

Liangge Xu 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: 8907710
    Abstract: A digitally controlled delay device includes at least one delay generating gate device, whose propagation delay is controlled by limiting operating current by means of a tail transistor that is controlled by its gate voltage, a gate control voltage control means for controlling the current limiting transistor gate voltage, and a bank of digitally controlled MOSFET transistors in parallel configuration, and the digital control is adapted to switch the transistors to off and to diode mode connection, current feeding means to feed current through the bank of MOSFET transistors, and the voltage over the bank of parallel transistors is used for gate source control voltage of the tail transistors.
    Type: Grant
    Filed: November 18, 2013
    Date of Patent: December 9, 2014
    Assignee: Broadcom Corporation
    Inventors: Liangge Xu, Kari Stadius, Jussi Ryynanen
  • Publication number: 20140113576
    Abstract: A preferred embodiment of the present invention relates generally to enhancing quality of a received signal in a receiver. The received signal can be enhanced by reducing phase noise. A described method starts with determining input information, wherein the input information comprises at least one of the following pieces of information: a modulation-and-coding scheme of the received signal, a multiple-antenna configuration (MIMO configuration), a signal quality estimate of the received signal, or a frequency separation between the received signal and a transmitted signal. The method continues with selecting a bandwidth value on the basis of the input information. The selecting should result in such a bandwidth value which has an advantageous effect to the quality of the received signal. This advantageous effect is achieved by performing the following: using the bandwidth value for generating a local oscillator signal, and shaping the received signal with the local oscillator signal.
    Type: Application
    Filed: October 16, 2013
    Publication date: April 24, 2014
    Applicant: Renesas Mobile Corporation
    Inventors: Markus NENTWIG, Liangge XU
  • Publication number: 20140077858
    Abstract: A digitally controlled delay device includes at least one delay generating gate device, whose propagation delay is controlled by limiting operating current by means of a tail transistor that is controlled by its gate voltage, a gate control voltage control means for controlling the current limiting transistor gate voltage, and a bank of digitally controlled MOSFET transistors in parallel configuration, and the digital control is adapted to switch the transistors to off and to diode mode connection, current feeding means to feed current through the bank of MOSFET transistors, and the voltage over the bank of parallel transistors is used for gate source control voltage of the tail transistors.
    Type: Application
    Filed: November 18, 2013
    Publication date: March 20, 2014
    Applicant: BROADCOM CORPORATION
    Inventors: Liangge XU, Kari STADIUS, Jussi RYYNANEN
  • Patent number: 8666012
    Abstract: An apparatus and method for operating a frequency synthesizer wherein a value of an first control signal associated with a fine frequency feedback loop connected to a signal generator is monitored, and a second control signal associated with a medium or coarse frequency feedback loop connected to the signal generator is adjusted based on the monitoring. The first and second control signals are then output to control the frequency synthesizer.
    Type: Grant
    Filed: October 20, 2011
    Date of Patent: March 4, 2014
    Assignee: Broadcom Corporation
    Inventors: Ari Vilander, Liangge Xu, Jounl Kristian Kaukovuori
  • Publication number: 20130099829
    Abstract: An apparatus and method for operating a frequency synthesizer wherein a value of an first control signal associated with a fine frequency feedback loop connected to a signal generator is monitored, and a second control signal associated with a medium or coarse frequency feedback loop connected to the signal generator is adjusted based on the monitoring. The first and second control signals are then output to control the frequency synthesizer.
    Type: Application
    Filed: October 20, 2011
    Publication date: April 25, 2013
    Inventors: Ari VILANDER, Liangge Xu, Kristian Jouni Kaukovuori
  • Patent number: 8063669
    Abstract: Described is an apparatus that includes a frequency source and a plurality of time domain direct digital synthesizers each having an input connected to an output of the frequency source and an output providing an output frequency signal. A particular time domain direct digital synthesizer includes a sigma-delta modulator that functions as a second order multi-stage noise shaping sigma-delta modulator. In one exemplary embodiment sigma-delta modulator outputs provide a unitary-weighted word used to switch certain unit capacitors that comprise part of a delay modulator to produce a time-varying delay having a time-averaged value that directly corresponds to a binary value appearing on a plurality of phase accumulator outputs.
    Type: Grant
    Filed: November 6, 2008
    Date of Patent: November 22, 2011
    Assignee: Nokia Corporation
    Inventors: Saska Lindfors, Kari Stadius, Liangge Xu, Tapio Rapinoja, Jussi Ryynanen, Risto H. S. Kaunisto, Aarno Parssinen
  • Patent number: 7948274
    Abstract: A method includes generating a plurality of reference phases of a reference signal and selecting a sub-phase from each of the plurality of reference phases to form a set of selected sub-phases. In the method selecting operates in response to synchronized outputs of a multi-phase phase accumulator that operates synchronously in accordance with one of the sub-phases of the set of sub-phases, and where the outputs of the multi-phase phase accumulator may be synchronized using at least one additional sub-phase.
    Type: Grant
    Filed: September 30, 2009
    Date of Patent: May 24, 2011
    Assignee: Nokia Corporation
    Inventors: Tapio Rapinoja, Liangge Xu
  • Publication number: 20110074469
    Abstract: A method includes generating a plurality of reference phases of a reference signal and selecting a sub-phase from each of the plurality of reference phases to form a set of selected sub-phases. In the method selecting operates in response to synchronized outputs of a multi-phase phase accumulator that operates synchronously in accordance with one of the sub-phases of the set of sub-phases, and where the outputs of the multi-phase phase accumulator may be synchronized using at least one additional sub-phase.
    Type: Application
    Filed: September 30, 2009
    Publication date: March 31, 2011
    Inventors: Tapio Rapinoja, Liangge Xu
  • Publication number: 20100109714
    Abstract: Described is an apparatus that includes a frequency source and a plurality of time domain direct digital synthesizers each having an input connected to an output of the frequency source and an output providing an output frequency signal. A particular time domain direct digital synthesizer includes a sigma-delta modulator that functions as a second order multi-stage noise shaping sigma-delta modulator. In one exemplary embodiment sigma-delta modulator outputs provide a unitary-weighted word used to switch certain unit capacitors that comprise part of a delay modulator to produce a time-varying delay having a time-averaged value that directly corresponds to a binary value appearing on a plurality of phase accumulator outputs.
    Type: Application
    Filed: November 6, 2008
    Publication date: May 6, 2010
    Inventors: Saska Lindfors, Kari Stadius, Liangge Xu, Tapio Rapinoja, Jussi Ryynanen, Risto H.S. Kaunisto, Aarno Parssinen