Patents by Inventor Joseph W. Fontes

Joseph W. Fontes 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).

  • GNSS time fraction calibration of a real time clock
    Patent number: 7791534
    Abstract: A generic navigation satellite system (GNSS) signal receiver having a fast time to first fix by calibrating a low power always-on real time clock (RTC). The receiver includes an RTC calibrator having a fraction calculator. The RTC calibrator may also include a time expander. Before the receiver is powered off, the fraction calculator uses the fine resolution of GNSS time for determining a time fraction for RTC time. When the receiver is powered back on, the time expander uses an estimate of RTC time drift during the time that GNSS receiver had power off and the time fraction for calibrating and increasing the resolution of the RTC time for an RTC time tick. A signal navigation processor uses the calibrated RTC time for assisting a first fix with code phase search, integration time periods, resolution of epoch integer and/or location-in-space of GPS satellites.
    Type: Grant
    Filed: March 13, 2009
    Date of Patent: September 7, 2010
    Assignee: Trimble Navigation Limited
    Inventors: Xiaorong Zhi, Yiming Yu, Joseph W. Fontes
  • Fast time to first fix by calibration of a real time clock
    Patent number: 7532159
    Abstract: A generic navigation satellite system (GNSS) signal receiver having a fast time to first fix by calibrating a low power always-on real time clock (RTC). The receiver includes an RTC calibrator having a fraction calculator. The RTC calibrator may also include a time expander. Before the receiver is powered off, the fraction calculator uses the fine resolution of GNSS time for determining a time fraction for RTC time. When the receiver is powered back on, the time expander uses an estimate of RTC time drift during the time that GNSS receiver had power off and the time fraction for calibrating and increasing the resolution of the RTC time for an RTC time tick. A signal navigation processor uses the calibrated RTC time for assisting a first fix with code phase search, integration time periods, resolution of epoch integer and/or location-in-space of GPS satellites.
    Type: Grant
    Filed: May 19, 2006
    Date of Patent: May 12, 2009
    Assignee: Trimble Navigation Limited
    Inventors: Xiaorong Zhi, Yiming Yu, Joseph W. Fontes
  • Fast time to first fix by calibration of a real time clock
    Publication number: 20070268180
    Abstract: A generic navigation satellite system (GNSS) signal receiver having a fast time to first fix by calibrating a low power always-on real time clock (RTC). The receiver includes an RTC calibrator having a fraction calculator and a time expander. Before the receiver is powered off, the fraction calculator uses the fine resolution of GNSS time for determining a time fraction for RTC time. When the receiver is powered back on, the time expander uses an estimate of RTC time drift during the time that GNSS receiver had power off and the time fraction for calibrating and increasing the resolution of the RTC time for an RTC time tick. A signal navigation processor uses the calibrated RTC time for assisting a first fix with code phase search, integration time periods, resolution of epoch integer and/or location-in-space of GPS satellites.
    Type: Application
    Filed: May 19, 2006
    Publication date: November 22, 2007
    Inventors: Xiaorong Zhi, Yiming Yu, Joseph W. Fontes