Patents by Inventor David Duane Chapman

David Duane Chapman 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: 11675090
    Abstract: Apparatus and methods permit the use of a microelectromechanical systems (MEMS) oscillator in a satellite positioning system receiver, such as a Global Positioning System (GPS) receiver. Techniques to ameliorate jitter or phase noise disadvantages associated with MEMS oscillators are disclosed. For example, a receiver can use one or more of the following techniques: (a) use another source of information to retrieve ephemeris information, (2) perform advanced tight coupling, and/or (3) use a phase-locked loop to clean up the jitter or phase noise of the MEMS oscillator. With respect to advanced tight coupling, an advanced tight coupling processor can include nonlinear discriminators which transform I and Q data into linear residual measurements corrupted by unbiased, additive, and white noise. It also includes an amplitude estimator configured to operate in rapidly changing, high power noise; a measurement noise variance estimator; and a linear residual smoothing filter for input to the navigation filter.
    Type: Grant
    Filed: December 1, 2020
    Date of Patent: June 13, 2023
    Assignee: L3Harris Interstate Electronics Corporation
    Inventors: David Duane Chapman, Steven B. Alexander
  • Patent number: 11101829
    Abstract: A radio receiver has a front end having a shared amplification path for both radio frequency signals and intermediate frequency signals. In one example, the shared amplification path can include a low noise amplifier and an attenuator. By amplifying both radio frequency (RF) signals and intermediate frequency (IF) signals with the same shared amplification path, gains in power efficiency, and reductions in cost and circuit size can be achieved.
    Type: Grant
    Filed: April 8, 2020
    Date of Patent: August 24, 2021
    Assignee: Interstate Electronics Corporation
    Inventor: David Duane Chapman
  • Patent number: 10866325
    Abstract: Apparatus and methods permit the use of a microelectromechanical systems (MEMS) oscillator in a satellite positioning system receiver, such as a Global Positioning System (GPS) receiver. Techniques to ameliorate jitter or phase noise disadvantages associated with MEMS oscillators are disclosed. For example, a receiver can use one or more of the following techniques: (a) use another source of information to retrieve ephemeris information, (2) perform advanced tight coupling, and/or (3) use a phase-locked loop to clean up the jitter or phase noise of the MEMS oscillator. With respect to advanced tight coupling, an advanced tight coupling processor can include nonlinear discriminators which transform I and Q data into linear residual measurements corrupted by unbiased, additive, and white noise. It also includes an amplitude estimator configured to operate in rapidly changing, high power noise; a measurement noise variance estimator; and a linear residual smoothing filter for input to the navigation filter.
    Type: Grant
    Filed: July 18, 2018
    Date of Patent: December 15, 2020
    Assignee: Interstate Electronics Corporation
    Inventors: David Duane Chapman, Steven B. Alexander
  • Patent number: 10637514
    Abstract: A radio receiver has a front end having a shared amplification path for both radio frequency signals and intermediate frequency signals. In one example, the shared amplification path can include a low noise amplifier and an attenuator. By amplifying both radio frequency (RF) signals and intermediate frequency (IF) signals with the same shared amplification path, gains in power efficiency, and reductions in cost and circuit size can be achieved.
    Type: Grant
    Filed: January 29, 2019
    Date of Patent: April 28, 2020
    Assignee: Interstate Electronics Corporation
    Inventor: David Duane Chapman
  • Patent number: 10200068
    Abstract: A radio receiver has a front end having a shared amplification path for both radio frequency signals and intermediate frequency signals. In one example, the shared amplification path can include a low noise amplifier and an attenuator. By amplifying both radio frequency (RF) signals and intermediate frequency (IF) signals with the same shared amplification path, gains in power efficiency, and reductions in cost and circuit size can be achieved.
    Type: Grant
    Filed: April 23, 2018
    Date of Patent: February 5, 2019
    Assignee: Interstate Electronics Corporation
    Inventor: David Duane Chapman
  • Patent number: 10107919
    Abstract: Apparatus and methods permit the use of a microelectromechanical systems (MEMS) oscillator in a satellite positioning system receiver, such as a Global Positioning System (GPS) receiver. Techniques to ameliorate jitter or phase noise disadvantages associated with MEMS oscillators are disclosed. For example, a receiver can use one or more of the following techniques: (a) use another source of information to retrieve ephemeris information, (2) perform advanced tight coupling, and/or (3) use a phase-locked loop to clean up the jitter or phase noise of the MEMS oscillator. With respect to advanced tight coupling, an advanced tight coupling processor can include nonlinear discriminators which transform I and Q data into linear residual measurements corrupted by unbiased, additive, and white noise. It also includes an amplitude estimator configured to operate in rapidly changing, high power noise; a measurement noise variance estimator; and a linear residual smoothing filter for input to the navigation filter.
    Type: Grant
    Filed: March 1, 2016
    Date of Patent: October 23, 2018
    Assignee: Interstate Electronics Corporation
    Inventors: David Duane Chapman, Steven B. Alexander
  • Patent number: 9979420
    Abstract: A radio receiver has a front end having a shared amplification path for both radio frequency signals and intermediate frequency signals. In one example, the shared amplification path can include a low noise amplifier and an attenuator. By amplifying both radio frequency (RF) signals and intermediate frequency (IF) signals with the same shared amplification path, gains in power efficiency, and reductions in cost and circuit size can be achieved.
    Type: Grant
    Filed: August 11, 2016
    Date of Patent: May 22, 2018
    Assignee: Interstate Electronics Corporation
    Inventor: David Duane Chapman
  • Patent number: 9515690
    Abstract: A radio receiver has a front end having a shared amplification path for both radio frequency signals and intermediate frequency signals. In one example, the shared amplification path can include a low noise amplifier and an attenuator. By amplifying both radio frequency (RF) signals and intermediate frequency (IF) signals with the same shared amplification path, gains in power efficiency, and reductions in cost and circuit size can be achieved.
    Type: Grant
    Filed: August 22, 2014
    Date of Patent: December 6, 2016
    Assignee: Interstate Electronics Corporation
    Inventor: David Duane Chapman
  • Patent number: 9356639
    Abstract: A radio receiver has a front end having a shared amplification path for both radio frequency signals and intermediate frequency signals. In one example, the shared amplification path can include a low noise amplifier and an attenuator. By amplifying both radio frequency (RF) signals and intermediate frequency (IF) signals with the same shared amplification path, gains in power efficiency, and reductions in cost and circuit size can be achieved.
    Type: Grant
    Filed: August 22, 2014
    Date of Patent: May 31, 2016
    Assignee: Interstate Electronics Corporation
    Inventor: David Duane Chapman
  • Patent number: 9246664
    Abstract: A radio receiver has a front end having a shared amplification path for both radio frequency signals and intermediate frequency signals. In one example, the shared amplification path can include a low noise amplifier and an attenuator. By amplifying both radio frequency (RF) signals and intermediate frequency (IF) signals with the same shared amplification path, gains in power efficiency, and reductions in cost and circuit size can be achieved.
    Type: Grant
    Filed: August 22, 2014
    Date of Patent: January 26, 2016
    Assignee: Interstate Electronics Corporation
    Inventor: David Duane Chapman