Patents by Inventor R. Douglas Schultz

R. Douglas Schultz 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).

  • Publication number: 20040127185
    Abstract: A multiple band transmitter including first and second transmit amplifier paths, where the first transmit amplifier path conducts a first transmit signal at a first frequency band and the second transmit amplifier path conducts a second transmit signal at a second frequency band. The second transmit amplifier path includes an amplifier that generates the second transmit signal along with a harmonic frequency within a passband of the first transmit amplifier path. The second transmit amplifier path further includes a trap circuit that shunts the harmonic frequency away from the first transmit amplifier path.
    Type: Application
    Filed: December 12, 2003
    Publication date: July 1, 2004
    Inventors: Richard L. Abrahams, R. Douglas Schultz, Adam K. Harriman, W. Joseph Vitek
  • Patent number: 6735422
    Abstract: A calibrated DC compensation system for a wireless communication device configured in a zero intermediate frequency (ZIF) architecture. The device includes a ZIF transceiver and a baseband processor, which further includes a calibrator that periodically performs a calibration procedure. The baseband processor includes gain control logic, DC control logic, a gain converter and the calibrator. The gain converter converts gain between the gain control logic and the DC control logic. The calibrator programs the gain converter with values determined during the calibration procedure. The gain converter may be a lookup table that stores gain conversion values based on measured gain of a baseband gain amplifier of the ZIF transceiver. The gain control logic may further include a gain adjust limiter that limits change of a gain adjust signal during operation based on a maximum limit or on one or more gain change limits.
    Type: Grant
    Filed: October 2, 2000
    Date of Patent: May 11, 2004
    Inventors: Keith R. Baldwin, Patrick J. Landy, Mark A. Webster, R. Douglas Schultz, John S. Prentice
  • Patent number: 6560448
    Abstract: A wireless communication device including a radio frequency (RF) circuit, a ZIF transceiver and a baseband processor. The ZIF transceiver includes an RF mixer circuit that converts the RF signal to a baseband input signal, a summing junction that subtracts a DC offset from the baseband input signal to provide an adjusted baseband input signal, and a baseband amplifier that receives the adjusted baseband input signal and that asserts an amplified input signal based on a gain adjust signal. The baseband processor includes gain control logic, DC control logic and a gain interface. The gain control logic receives the amplified input signal, estimates input signal power and asserts the gain adjust signal in an attempt to keep the input signal power at a target power level. The DC control logic estimates an amount of DC in the amplified input signal and provides the DC offset in an attempt to reduce DC in the amplified input signal.
    Type: Grant
    Filed: October 2, 2000
    Date of Patent: May 6, 2003
    Assignee: Intersil Americas Inc.
    Inventors: Keith R. Baldwin, Patrick J. Landy, Mark A. Webster, R. Douglas Schultz, John S. Prentice