Patents by Inventor Hongliang Zhang

Hongliang Zhang 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: 6160839
    Abstract: A new method makes the most efficient use of the scarce spectral bandwidth in a wireless discrete multitone spread spectrum communications system by updating the spectral and/or spatial spreading weights at a rate that is determined by the measured quality of the link. Low quality links require more frequent updates of the spreading weights than do higher quality links. Spreading weights and despreading weights for a station are adaptively updated, depending on the error in received signals. If the error value is less than a threshold error value, then the method maintains the existing spreading weights as the current spreading weights to apply to an outgoing data signal. Alternately, if the error value is greater than the threshold error value, then the method adaptively calculates updated despreading weights at the base station from the first spread signal and calculates updated spreading weights as the current spreading weights from the updated despreading weights to apply to the outgoing data signal.
    Type: Grant
    Filed: April 26, 1999
    Date of Patent: December 12, 2000
    Assignee: AT&T Wireless Svcs. Inc.
    Inventor: Hongliang Zhang
  • Patent number: 5933421
    Abstract: The high quality PCS communications are enabled in environments where adjacent PCS service bands operate with out-of-band harmonics that would otherwise interfere with the system's operation. The highly bandwidth-efficient communications method combines a form of time division duplex (TDD), frequency division duplex (FDD), time division multiple access (TDMA), orthogonal frequency division multiplexing (OFDM), spatial diversity, and polarization diversity in various unique combinations. The method provides excellent fade resistance. The method enables changing a user's available bandwidth on demand by assigning additional TDMA slots during the user's session.
    Type: Grant
    Filed: February 6, 1997
    Date of Patent: August 3, 1999
    Assignee: AT&T Wireless Services Inc.
    Inventors: Siavash Alamouti, Eduardo F. Casas, Michael Hirano, Elliott Hoole, Mary Jesse, David G. Michelson, Patrick Poon, Gregory J. Veintimilla, Hongliang Zhang
  • Patent number: 5923700
    Abstract: A new method makes the most efficient use of the scarce spectral bandwidth in a wireless discrete multitone spread spectrum communications system by updating the spectral and/or spatial spreading weights at a rate that is determined by the measured quality of the link. Low quality links require more frequent updates of the spreading weights than do higher quality links. Spreading weights and despreading weights for a station are adaptively updated, depending on the error in received signals. If the error value is less than a threshold error value, then the method maintains the existing spreading weights as the current spreading weights to apply to an outgoing data signal. Alternately, if the error value is greater than the threshold error value, then the method adaptively calculates updated despreading weights at the base station from the first spread signal and calculates updated spreading weights as the current spreading weights from the updated despreading weights to apply to the outgoing data signal.
    Type: Grant
    Filed: February 24, 1997
    Date of Patent: July 13, 1999
    Assignee: AT & T Wireless
    Inventor: Hongliang Zhang