Patents by Inventor Chao Wang, legal representative

Chao Wang, legal representative 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).

  • Methods and apparatus for turbo space-time trellis coding
    Patent number: 7843888
    Abstract: Space-time diversity using a plurality of transmit antennas is provided with a turbo coding arrangement comprising two recursive systematic convolutional coders, to one of which input bits are supplied directly and to the other of which the information bits are supplied after interleaving of bit groups for respective symbol intervals. Symbols produced by the coders and comprising systematic and parity information are supplied to paths to the antennas alternately in successive symbol intervals to provide the space-time diversity. Arrangements are described for 2 and 4 antennas and for various convolutional codes, and an iterative decoder is also described.
    Type: Grant
    Filed: November 22, 2000
    Date of Patent: November 30, 2010
    Assignee: Nortel Networks Limited
    Inventors: Rui R. Wang, Chao Wang, legal representative, Ming Jia, Yuri S. Shinakov, Alexandre M. Chloma, Mikhail G. Bakouline, Vitali B. Kreindeline
  • Channel estimation in CDMA communications systems using both lower power pilot channel and higher power date channel
    Patent number: 7379513
    Abstract: An iterative arrangement of channel estimator (12), a Kalman filter unit (14), and a soft demodulator (16) is provided for producing an estimate of complex gain of a CDMA communications channel carrying data and pilot channels, and demodulated data of the data channel. An initial channel estimate is produced by the estimator (12) using only the low-power pilot channel. This later is improved by the iterative process using the data channel. The complex gains is represented by a sum of sinusoidal signals with different frequencies and randomly variable amplitude and phase.
    Type: Grant
    Filed: May 23, 2001
    Date of Patent: May 27, 2008
    Inventors: Chao Wang, legal representative, Mohamed El-Tarkhuni, Zhi Ding, Yuri S. Shinakov, Alexandre M Chloma, Mikhail G. Bakouline, Vitali B. Kreindeline, Rui R. Wang
  • Multi-user detection in CDMA communications system
    Patent number: 7327713
    Abstract: For each user in a multi-user detection arrangement in a CDMA communications system, a detector (80) provides a limiting function (88) responsive to a combined signal to produce a detection signal, having any of at least three possible values, for supply to a signal regenerator, regenerated signals being subtracted from a received signal in successive detection iterations of the multi-user detection arrangement. A code correlated signal is supplied via an inverse hyperbolic tangent function (84), or is multiplied by a multiplier inverse to an iteration index, to produce a derived signal. The derived signal is added (86) to a representation of a detection result stored from a previous iteration to produce the combined signal. The limiting function can comprise a hyperbolic tangent function.
    Type: Grant
    Filed: September 13, 2001
    Date of Patent: February 5, 2008
    Inventors: Chao Wang, legal representative, Wen Tong, Philip Thomas, Yuri S. Shinakov, Alexandere M. Chloma, Mikhail G. Bakouline, Vitali B. Kreindeline, Rui R. Wang, deceased