Patents by Inventor Mao Zhu Zhang

Mao Zhu 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: 7671778
    Abstract: In a cable return path system, a method for performing digital companding adds a predetermined offset to the digital value to be companded, and employs a modified ?-law or a-law companding technique to obtain a reduced bit length digital value. One embodiment of this modified approach adds a predetermined offset (e.g., 129 for a 12-bit implementation) to the digital value before companding and then employs a two-bit chord and a 5-bit step for the 12-bit implementation. The end result is that the performance metrics are not significantly compromised by this bit reduction when compared to current transmission methods without this technique.
    Type: Grant
    Filed: June 18, 2003
    Date of Patent: March 2, 2010
    Assignee: General Instrument Corporation
    Inventors: Mao Zhu Zhang, Robert L. Howald
  • Publication number: 20040261120
    Abstract: In a cable return path system, a method for performing digital companding adds a predetermined offset to the digital value to be companded, and employs a modified &mgr;-law or a-law companding technique to obtain a reduced bit length digital value. One embodiment of this modified approach adds a predetermined offset (e.g., 129 for a 12-bit implementation) to the digital value before companding and then employs a two-bit chord and a 5-bit step for the 12-bit implementation. The end result is that the performance metrics are not significantly compromised by this bit reduction when compared to current transmission methods without this technique.
    Type: Application
    Filed: June 18, 2003
    Publication date: December 23, 2004
    Applicant: General Instrument Corporation
    Inventors: Mao Zhu Zhang, Robert L. Howald