Patents by Inventor Francis Chan Wai Po

Francis Chan Wai Po 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).

  • ADAPTIVE RADIO FREQUENCY FILTER WITH IMPROVED LINEARITY
    Publication number: 20230178867
    Abstract: An adaptive radio frequency including an input, an output, at least one fixed passive inductor and at least one variable active inductor connected between the input and the output.
    Type: Application
    Filed: November 30, 2022
    Publication date: June 8, 2023
    Inventors: Francis CHAN WAI PO, Vincent PETIT, Bruno LOUIS
  • Impedance matching method for a multiband antenna, and transmission or receiver channel having automatic matching
    Patent number: 9041611
    Abstract: An automatic antenna impedance matching method for a radiofrequency transmission circuit. An impedance matching network is inserted between an amplifier and an antenna. The output current and voltage of the amplifier and their phase difference are measured by a variable measurement impedance, and the complex load impedance of the amplifier is deduced from this; the impedance of the antenna is calculated as a function of this complex impedance and as a function of the known current values of the impedances of the matching network. Starting from the value found for the impedance of the antenna, new values of the matching network are calculated that allow the load to be matched to the nominal impedance of the amplifier. The measurement impedance has a value controllable by the calculation processor according to the application and notably as a function of the operating frequency and of the nominal impedance of the amplifier.
    Type: Grant
    Filed: September 1, 2010
    Date of Patent: May 26, 2015
    Assignee: Commissariat A L'Energie Atomique et aux Energies Alternatives
    Inventors: Francis Chan Wai Po, Emeric De Foucauld
  • IMPEDANCE MATCHING METHOD FOR A MULTIBAND ANTENNA, AND TRANSMISSION OR RECEIVER CHANNEL HAVING AUTOMATIC MATCHING
    Publication number: 20120169566
    Abstract: An automatic antenna impedance matching method for a radiofrequency transmission circuit. An impedance matching network is inserted between an amplifier and an antenna. The output current and voltage of the amplifier and their phase difference are measured by a variable measurement impedance, and the complex load impedance of the amplifier is deduced from this; the impedance of the antenna is calculated as a function of this complex impedance and as a function of the known current values of the impedances of the matching network. Starting from the value found for the impedance of the antenna, new values of the matching network are calculated that allow the load to be matched to the nominal impedance of the amplifier. The measurement impedance has a value controllable by the calculation processor according to the application and notably as a function of the operating frequency and of the nominal impedance of the amplifier.
    Type: Application
    Filed: September 1, 2010
    Publication date: July 5, 2012
    Inventors: Francis Chan Wai Po, Emeric De Foucauld
  • Method for automatic impedance matching for a radiofrequency circuit and transmission or reception system with automatic matching
    Patent number: 8140033
    Abstract: The invention relates to a method for automatically matching the antenna impedance for a radiofrequency transmission circuit having an amplifier. An impedance matching network is inserted between the amplifier and the antenna. The output current i and voltage V from the amplifier and their phase shift are measured, and from this the complex impedance, defined by V/i, is deduced. The antenna impedance is calculated as a function of this complex impedance and as a function of the known present values of the adjustable impedances of the matching network. New values are calculated, from the calculated value of the antenna impedance, for the adjustable impedances of the matching network that allow an overall load impedance of the amplifier to be obtained which is as close as possible to the nominal load impedance Zopt of the amplifier, and the matching network is controlled to adjust the adjustable impedances to these new values.
    Type: Grant
    Filed: September 10, 2008
    Date of Patent: March 20, 2012
    Assignee: Commissariat a l'Energie Atomique
    Inventors: Francis Chan Wai Po, Emeric De Foucauld, Pierre Vincent
  • METHOD FOR AUTOMATIC IMPEDANCE MATCHING FOR A RADIOFREQUENCY CIRCUIT AND TRANSMISSION OR RECEPTION SYSTEM WITH AUTOMATIC MATCHING
    Publication number: 20090066440
    Abstract: The invention relates to a method for automatically matching the antenna impedance for a radiofrequency transmission circuit having an amplifier. An impedance matching network is inserted between the amplifier and the antenna. The output current i and voltage V from the amplifier and their phase shift are measured, and from this the complex impedance, defined by V/i, is deduced. The antenna impedance is calculated as a function of this complex impedance and as a function of the known present values of the adjustable impedances of the matching network. New values are calculated, from the calculated value of the antenna impedance, for the adjustable impedances of the matching network that allow an overall load impedance of the amplifier to be obtained which is as close as possible to the nominal load impedance Zopt of the amplifier, and the matching network is controlled to adjust the adjustable impedances to these new values.
    Type: Application
    Filed: September 10, 2008
    Publication date: March 12, 2009
    Applicant: COMMISSARIAT A L'ENERGIE ATOMIQUE
    Inventors: Francis Chan Wai Po, Emeric De Foucauld, Pierre Vincent