Patents by Inventor Christopher David Grondahl

Christopher David Grondahl 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).

  • Sampling phase detector and multiple frequency band termination circuit and method
    Patent number: 5953645
    Abstract: A multiple band termination circuit, comprising a first resistor coupled in signal communication with an input and an open stub to form a nominal termination at a high frequency band, and a second resistor coupled in series to the first resistor with a high impedance transmission line, the second resistor and the first resistor cooperating together to form a nominal termination at a low frequency band.
    Type: Grant
    Filed: January 20, 1998
    Date of Patent: September 14, 1999
    Assignee: Motorola, Inc.
    Inventor: Christopher David Grondahl
  • Method and apparatus for reducing distortion in a high efficiency power amplifier
    Patent number: 5936464
    Abstract: A method and apparatus for efficient power amplification of a wideband signal with a correspondingly wide modulation bandwidth includes an envelope detector (220), an envelope amplifier (270), a driver amplifier (250), and a power amplifier (260). The driver amplifier (250) includes a dual gate variable gain amplifier (252) that has a substantially constant phase characteristic over a wide dynamic range. The power amplifier (260) is modulated by an amplified envelope signal from the envelope amplifier (270), and is driven by an output of the driver amplifier (250). The operation of the cascaded driver amplifier (250) and power amplifier (260) allow the power amplifier (260) to operate a substantially constant compression point, and reduced distortion.
    Type: Grant
    Filed: November 3, 1997
    Date of Patent: August 10, 1999
    Assignee: Motorola, Inc.
    Inventor: Christopher David Grondahl
  • High dynamic range millimeter wave power detector with temperature compensation
    Patent number: 5873029
    Abstract: An RF power detector (10) includes an RF detector circuit (12), a nonlinear feedback amplifier (14), a temperature compensation circuit (16) and a linear feedback amplifier circuit (18). The RF detector circuit converts an RF signal to a voltage representative of the RF signals power level. Nonlinear feedback amplifier (14) nonlinearly amplifies the voltage and compensates for the nonlinearities of the RF detector circuits detector elements. Temperature compensation element provides a temperature compensation signal to compensate for the temperature effects of the detector elements of RF detector circuit (12). The output signal of RF power detector (10) is a substantially linearly representation of the RF input signals power level. Nonlinear feedback amplifier (14) includes a nonlinear feedback circuit (30) with a nonlinear feedback element (32) in the feedback path of op-amp (42).
    Type: Grant
    Filed: February 19, 1997
    Date of Patent: February 16, 1999
    Assignee: Motorola, Inc.
    Inventors: Christopher David Grondahl, David Warren Corman, Kenneth Vern Buer