Patents by Inventor Mingzheng Cao

Mingzheng Cao 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).

  • Carrier frequency offset (CFO) estimator with low complexity and high accuracy for orthogonal-frequency-division-multiplexing (CO-OFDM) systems
    Patent number: 8705956
    Abstract: A system and method are provided for carrier frequency offset (CFO) estimation for coherent optical orthogonal-frequency-division-multiplexing (CO-OFDM) broadband systems. The method includes obtaining an initial estimate of a normalized CFO with an estimation range equal to ±L/2 subcarrier subspacing using a single training symbol with L identical portions. The method further includes obtaining a maximum likelihood (ML) estimate of the CFO by performing a local grid search based on the initial estimate.
    Type: Grant
    Filed: April 14, 2011
    Date of Patent: April 22, 2014
    Assignee: NEC Laboratories America, Inc.
    Inventors: Mingzheng Cao, Dayou Qian
  • CARRIER FREQUENCY OFFSET (CFO) ESTIMATOR WITH LOW COMPLEXITY AND HIGH ACCURACY FOR ORTHOGONAL-FREQUENCY-DIVISION-MULTIPLEXING (CO-OFDM) SYSTEMS
    Publication number: 20110255864
    Abstract: A system and method are provided for carrier frequency offset (CFO) estimation for coherent optical orthogonal-frequency-division-multiplexing (CO-OFDM) broadband systems. The method includes obtaining an initial estimate of a normalized CFO with an estimation range equal to ±L/2 subcarrier subspacing using a single training symbol with L identical portions. The method further includes obtaining a maximum likelihood (ML) estimate of the CFO by performing a local grid search based on the initial estimate.
    Type: Application
    Filed: April 14, 2011
    Publication date: October 20, 2011
    Applicant: NEC Laboratories America, Inc.
    Inventors: Mingzheng Cao, Dayou Qian