Patents by Inventor Charles John Razzell

Charles John Razzell 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: 8958769
    Abstract: A direct conversion receiver including an input stage, a frequency modulated local oscillator, a mixer stage, an output stage, and a DC blocker stage coupled between the mixer stage and the output stage. The input stage is receptive to a frequency modulated transmission having a carrier frequency fc and the frequency modulated local oscillator provides a frequency modulated local oscillator signal. In an embodiment, the frequency modulated local oscillator includes a local oscillator having an output with a frequency approximately equal to fc, a modulation source having a modulation signal output, and a frequency modulator coupled to the outputs of the local oscillator.
    Type: Grant
    Filed: August 31, 2012
    Date of Patent: February 17, 2015
    Assignee: Maxim Integrated Products, Inc.
    Inventor: Charles John Razzell
  • Patent number: 8442171
    Abstract: Embodiments of the present invention provide systems, devices and methods for modeling and correcting amplitude and quadrature phase errors generated within analog components of a receiver. A frequency-dependent correction method is employed that closely tracks the frequency dependent nature of the mismatch between the I and Q polyphase filter responses. In particular, digital correction is performed on a signal based on a modeled error function generated during a calibration of the receiver.
    Type: Grant
    Filed: September 27, 2011
    Date of Patent: May 14, 2013
    Assignee: Maxim Integrated Products, Inc.
    Inventor: Charles John Razzell
  • Publication number: 20120087451
    Abstract: Embodiments of the present invention provide systems, devices and methods for modeling and correcting amplitude and quadrature phase errors generated within analog components of a receiver. A frequency-dependent correction method is employed that closely tracks the frequency dependent nature of the mismatch between the I and Q polyphase filter responses.
    Type: Application
    Filed: September 27, 2011
    Publication date: April 12, 2012
    Inventor: Charles John Razzell
  • Patent number: 6901105
    Abstract: A resolved component of a multi-path signal is assigned to a rake finger of a spread spectrum rake receiver. The resolved component is variably delayed. On the variably delayed resolved component, an early-late detection is performed so as to determine whether the resolved component arrived early or late with respect to an optimum arrival time. A first pulse is generated if the early-late detection determines that said resolved component arrived early. A second pulse is generated if the early-late detection determines that the resolved component arrived late. The first and second pulses are counted. The first pulse causes counting in a first direction and the second pulse causes counting in a second direction. From the counting, a fractional-chip delay timing adjustment signal is derived, and fed back to adjust the variably delaying of the resolved component. Also from the counting a chip delay phase adjustment signal is derived, and fed back to control a phase of a pseudo-noise generator.
    Type: Grant
    Filed: August 28, 2000
    Date of Patent: May 31, 2005
    Assignee: Koninklijke Philips Electroncs N.V.
    Inventor: Charles John Razzell