Patents by Inventor R. Douglas Beards

R. Douglas Beards 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).

  • Phase shifter using sine and cosine weighting functions
    Patent number: 6417712
    Abstract: Sine and cosine weighting functions are applied to phase quadrature versions of an input signal to be phase shifted, and the weighted results are summed to provide a phase shifted output signal with an amplitude which is relatively independent of the phase shift. A weighting circuit comprises two translinear sine shaping circuits having differential current outputs providing weighting signals from input currents supplied thereto, the input currents of the two sine shaping circuits being offset relative to one another so that the differential current outputs of the two sine shaping circuits are provided in accordance with a sine function and a cosine function, respectively, of a control signal.
    Type: Grant
    Filed: September 27, 2000
    Date of Patent: July 9, 2002
    Assignee: Nortel Networks Limited
    Inventors: R. Douglas Beards, John J. Nisbet, Qi Tang, Eric Gagnon