Patents by Inventor Patrick L. Lim

Patrick L. Lim 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: 5267272
    Abstract: The invention is an automatic gain control (AGC) sampling structure in which a conventional closed loop AGC circuit detects a received level and generates a direct current voltage for controlling an amplification stage. This direct current voltage is sampled and the optimum control voltage is selected from the samples based on the technique of ordered statistics. The conventional AGC control loop is interrupted and the selected control voltage is provided to the amplification stage.
    Type: Grant
    Filed: February 14, 1991
    Date of Patent: November 30, 1993
    Assignee: Hughes Aircraft Company
    Inventors: Khiem V. Cai, James L. Thomas, Patrick L. Lim
  • Patent number: 5029182
    Abstract: The invention is an Automatic Gain Control ("AGC") sampling structure for use with frequency-hopped high frequency waveforms containing known transmitted signals embedded within communications traffic. The sampling structure is a digital structure and an AGC selection algorithm used in conjunction with a standard closed loop analog AGC circuit in which the AGC generator detects the received audio level and generates a direct current control voltage for controlling an amplification stage. This AGC control voltage is sampled during the reception of known transmitted signals to provide a series of independent AGC samples to a digital controller. The digital controller determines th eoptimum AGC control voltage based on a selection algorithm which uses the technique of ordered statistics to select the correct ordered sample to provide the optimum AGC control level for the receiver.
    Type: Grant
    Filed: March 5, 1990
    Date of Patent: July 2, 1991
    Assignee: Hughes Aircraft Company
    Inventors: Khiem V. Cai, James L. Thomas, Patrick L. Lim