Patents by Inventor Patrick C. Fenton

Patrick C. Fenton 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: 20100103030
    Abstract: A system for determining positions of fixed-position satellite signal receivers that have restricted views of the sky includes a data recording control center, and one or more base satellite signal receivers with associated antennas that together have substantially unrestricted views of the sky. The system batch processes range information provided by the fixed-position receivers over an extended period of time, determining the three dimensional position of a given fixed-position receiver using range data from at least three relatively short time intervals associated with different sky positions in which the receiver is tracking any two or more satellite signals simultaneously.
    Type: Application
    Filed: January 5, 2010
    Publication date: April 29, 2010
    Inventor: Patrick C. Fenton
  • Patent number: 7668228
    Abstract: A receiver for position-determining ranging signals transmitted by earth-orbiting satellites uses a set of accumulators, each of which accumulates signal samples corresponding with a position along the rising edges of incoming PRN pulses. An MMT processor calculates the rising edges of the direct path component of the received signal, selects the accumulator whose content correspond to a reference value related to the pulse height of the direct path component and compares the timing of the samples in that accumulator with the timing of the reference value on a reference pulse.
    Type: Grant
    Filed: September 13, 2006
    Date of Patent: February 23, 2010
    Assignee: NovAtel Inc.
    Inventors: Walter J. Feller, Patrick C. Fenton, Graham Purves
  • Patent number: 7668657
    Abstract: A system for determining positions of fixed-position GPS receives that have restricted views of the sky includes a data recording and control center, and one or more base GPS receivers with associated antennas with a substantially unrestricted views of the sky. The system batch processes range information provided by the fixed-position GPS receivers over an extended period of time; determining which of the range data from the fixed-position receivers are valid, and using the valid range data to determine position. In this way, the precise positions of the respective fixed-position slave GPS receivers can be calculated, even if the fixed-position GPS receivers are able to observe and collect data from sets of two or more satellites for only three or four relatively short time intervals at various sky positions during the extended period.
    Type: Grant
    Filed: August 8, 2007
    Date of Patent: February 23, 2010
    Assignee: NovAtel Inc.
    Inventor: Patrick C. Fenton
  • Publication number: 20090322601
    Abstract: A GNSS receiver reduces the time to first fix by utilizing the properties of existing radiated signals of opportunity, such as AM or FM radio signals, television signals and so forth, to reduce the uncertainties associated with oscillator frequency and phase , and further utilizing an Almanac and battery backed-up date and time to determine the satellites in view and reduce the uncertainties associated with Doppler. The receiver may use multiple signals of opportunity to determine the city or local area in which the receiver is located based on the set of frequencies of the signals, and also to reduce search uncertainties for oscillator frequency by estimating an offset based on the differences between the frequencies of the respective signals of opportunity at the receiver and the nominal broadcast frequencies of the signals.
    Type: Application
    Filed: May 22, 2009
    Publication date: December 31, 2009
    Inventors: Jonathan Ladd, Patrick C. Fenton
  • Publication number: 20090175319
    Abstract: A receiver includes a pre-correlation filter that forms an image of the average chip shape of a received signal over a specified period of time. The filter includes an array of complex accumulation registers that accumulate measurements that are associated with signal samples from specific ranges of locations, or code chip phase angles, along a spread-spectrum chip. Using the accumulated measurements, the receiver estimates the location of the chip transitions in a direct path signal component. The receiver may thereafter change the starting point, size and number of ranges, such that the accumulation registers accumulate more detail from the chip edges. The receiver in addition may compare the accumulated measurements with a reference pulse shape to determine if any interference is present in the received transmission that will distort ranging information calculated from the received signal.
    Type: Application
    Filed: March 19, 2009
    Publication date: July 9, 2009
    Inventor: Patrick C. Fenton
  • Publication number: 20090121940
    Abstract: A system to determine position, frequency and clock offsets over a network utilizing signals of opportunity transmitted by one or more transmitters with known locations, the system includes a base receiver with a clock and a known position that determines ranges to the transmitters, takes a series of samples of the signals of opportunity and time tags the series with times of receipt, calculated times of transmission based on the calculated ranges, or both. The base receiver transmits the time tagged series and, as appropriate, computed ranges to the remote receivers. A given remote receiver saves and time tags samples of the signals of opportunity, correlates the time-tagged series with the saved samples, and calculates a time offset as a time difference of the times of receipt at the remote receiver and either the time of receipt at the base receiver or the time of transmission calculated at the base receiver.
    Type: Application
    Filed: November 13, 2008
    Publication date: May 14, 2009
    Inventors: Jonathan Ladd, Patrick C. Fenton
  • Publication number: 20090117928
    Abstract: A system to distribute accurate time and/or frequency over a network utilizing signals of opportunity transmitted by one or more local transmitters with known locations, the system includes a base receiver with a clock synchronized to a reference time scale such as GNSS or UTC time that saves a series of samples of the signals of opportunity and time tags the series with a calculated time of broadcast. A remote receiver saves samples of the signals of opportunity and correlates the series with the saved samples. The remote receiver calculates a time of transmission of saved samples that correspond to the series, determines a time offset as a difference in the time of broadcast calculated at the remote receiver and the time of broadcast calculated at the base receiver, and determines the time offset with respect to the base receiver.
    Type: Application
    Filed: November 3, 2008
    Publication date: May 7, 2009
    Inventors: Jonathan Ladd, Patrick C. Fenton
  • Patent number: 7526386
    Abstract: A deformation monitoring system includes a data recording and control center, one or more base receivers with associated antennas that have a substantially unrestricted view of the sky and acquire and track satellite signals used for global positioning and slave receivers at various locations over the site being monitored, the slave receivers also acquiring and tracking the satellite signals. The system processes range information provided by the slave receivers over an extended period of time to determine the positions of the respective slave receivers. In this way, the precise positions of the respective slave receivers can be calculated, even if the slave receivers are able to observe and collect data from one or more satellites for only three or four relatively short time intervals at various sky positions during the extended period.
    Type: Grant
    Filed: August 10, 2006
    Date of Patent: April 28, 2009
    Assignee: NovAtel Inc.
    Inventor: Patrick C. Fenton
  • Publication number: 20090012712
    Abstract: A system for analyzing three-dimensional seismic data includes a plurality of digitizer units, each with a configuration of geophones, a data recording and control center, a base GPS receiver with an associated antenna with a substantially unrestricted view of the sky and at the respective digitizer units low-power slave GPS receivers that acquire and track GPS satellite signals using tracking assistance information provided by the base GPS receiver. The slave GPS receivers use the tracking assistance information to acquire and track GPS satellite signals that may be relatively weak at the receivers, due to conditions at the site, such as foliage canopies and so forth. The system processes range information provided by the slave GPS receivers over an extended period of time.
    Type: Application
    Filed: September 17, 2008
    Publication date: January 8, 2009
    Applicants: NovAtel Inc., ARAM Systems Ltd.
    Inventors: Patrick C. FENTON, Norman David Heidebrecht
  • Publication number: 20080297407
    Abstract: A GNSS receiver and antenna system transmits signals from an antenna structure to a remote GNSS receiver and includes a digital communications subsystem that utilizes a high speed digital communications conductor. The transmissions are digital signals that preserve GNSS satellite signal frequency and/or carrier and code phase information. The system may transmit digital signals corresponding to GNSS signals such as GPS, GLONAS, Galileo and Compass satellite signals. In addition, the system may transmit, over the same digital communications conductor in appropriately formatted digital signals, ranging signals from ground-based transmitters or other satellites, differential GNSS correction signals from beacons or base GPS receivers, and/or signals from transmitting or co-located sensors, such as inertial sensors, temperature sensors and so forth.
    Type: Application
    Filed: May 23, 2008
    Publication date: December 4, 2008
    Inventor: Patrick C. Fenton
  • Patent number: 7460615
    Abstract: A multi-band receiver for use with satellite ranging systems is provided. The receiver has a simplified architecture in which input signals of various frequencies are multiplexed together to form a single composite analog signal. In accordance with one embodiment of the invention, this composite signal only requires a single RF circuit for down conversion to an intermediate frequency. The composite, downconverted signal is sampled, and the digitized samples are demultiplexed to form digital counterparts of the original signals from each frequency band. An embodiment for use with elements of a phased array antenna is also provided.
    Type: Grant
    Filed: April 12, 2005
    Date of Patent: December 2, 2008
    Assignee: NovAtel, Inc.
    Inventors: Waldemar Kunysz, Patrick C. Fenton
  • Patent number: 7117094
    Abstract: A system for analyzing three-dimensional seismic data includes a plurality of digitizer units, each with a configuration of geophones, a data recording and control center, a base GPS receiver with an associated antenna with a substantially unrestricted view of the sky and at the respective digitizer units low-power slave GPS receivers that acquire and track GPS satellite signals using tracking assistance information provided by the base GPS receiver. The slave GPS receivers use the tracking assistance information to acquire and track GPS satellite signals from which the slave GPS receivers produce associated range information. The system batch processes the range information provided by the slave GPS receivers over an extended period of time to determine the precise positions of the respective slave GPS receivers. The system provides the position information to the slave GPS receivers, and the receivers locally produce associated timing signals that are based on the GPS codes.
    Type: Grant
    Filed: July 15, 2004
    Date of Patent: October 3, 2006
    Assignee: NovAtel, Inc.
    Inventor: Patrick C. Fenton
  • Publication number: 20040208236
    Abstract: A receiver includes a pre-correlation filter that forms an image of the average chip shape of a received signal over a specified period of time. The filter includes an array of complex accumulation registers that accumulate measurements that are associated with signal samples from specific ranges of locations, or code chip phase angles, along a spread-spectrum chip. Using the accumulated measurements, the receiver estimates the location of the chip transitions in a direct path signal component. The receiver may thereafter change the starting point, size and number of ranges, such that the accumulation registers accumulate more detail from the chip edges. The receiver in addition may compare the accumulated measurements with a reference pulse shape to determine if any interference is present in the received transmission that will distort ranging information calculated from the received signal.
    Type: Application
    Filed: April 13, 2004
    Publication date: October 21, 2004
    Inventor: Patrick C. Fenton
  • Patent number: 6728637
    Abstract: A track model is created for use with a GPS receiver. In one embodiment, the track model is a set of planar surfaces which approximate the contiguous surface on which navigation takes place. The GPS receiver searches for an appropriate planar surface associated with its approximate position. Having found the appropriate planar surface, the GPS receiver constrains its position using the planar surface associated with its approximate position. Using the track model improves the accuracy of the computed position at the time and improves the ambiguity estimation process so that positions with greatly improved accuracy are available sooner.
    Type: Grant
    Filed: June 22, 2001
    Date of Patent: April 27, 2004
    Assignee: Sportvision, Inc.
    Inventors: Thomas J. Ford, Patrick C. Fenton, James O. McGuffin, Stanley K. Honey
  • Patent number: 6618004
    Abstract: Multiple geographically fixed reference stations, with precisely known locations, that each receive GPS signals send information to a central processing facility that generates a three dimension topographical gradient map or model of the differences between the known locations and the locations as calculated from the received GPS signals. GPS signals received by mobile users are communicated to the central processing facility whereupon the central processing facility, using the model, generates precise corrected locations of the mobile users which is sent back to the mobile users. The mobile users can use and display the locally generated position from the locally received GPS signals or the corrected position from the central processing facility.
    Type: Grant
    Filed: May 7, 2001
    Date of Patent: September 9, 2003
    Assignee: NovAtel, Inc.
    Inventors: Patrick C. Fenton, Graham Purves, Douglas Reid
  • Publication number: 20030036849
    Abstract: A track model is created for use with a GPS receiver. In one embodiment, the track model is a set of planar surfaces which approximate the contiguous surface on which navigation takes place. The GPS receiver searches for an appropriate planar surface associated with its approximate position. Having found the appropriate planar surface, the GPS receiver constrains its position using the planar surface associated with its approximate position. Using the track model improves the accuracy of the computed position at the time and improves the ambiguity estimation process so that positions with greatly improved accuracy are available sooner.
    Type: Application
    Filed: September 20, 2002
    Publication date: February 20, 2003
    Inventors: Thomas J. Ford, Patrick C. Fenton, James O. McGuffin, Stanley K. Honey
  • Patent number: 6445340
    Abstract: A time signal generation system produces a reference time signal based on the signals transmitted by geostationary satellites, such as the satellites in the Wide Area Augmentation System (WAAS). A receiver in the system includes a directional antenna that is focused on the signals transmitted by the geostationary satellite. The antenna rejects multipath signals, and the receiver thus tracks the satellite signal directly, without having to compensate for multipath distortion. Once the receiver is tracking the code and carrier, the receiver decodes the transmitted data to recover timing information, as well as satellite orbital correction information and an ionospheric model, or table, transmitted by the satellite. The receiver then uses the decoded information and timing pulses provided in synchronism with the transmitted PRN code to produce a corrected timing signal.
    Type: Grant
    Filed: January 26, 2001
    Date of Patent: September 3, 2002
    Assignee: NovAtel, Inc.
    Inventor: Patrick C. Fenton
  • Publication number: 20020107636
    Abstract: A track model is created for use with a GPS receiver. In one embodiment, the track model is a set of planar surfaces which approximate the contiguous surface on which navigation takes place. The GPS receiver searches for an appropriate planar surface associated with its approximate position. Having found the appropriate planar surface, the GPS receiver constrains its position using the planar surface associated with its approximate position. Using the track model improves the accuracy of the computed position at the time and improves the ambiguity estimation process so that positions with greatly improved accuracy are available sooner.
    Type: Application
    Filed: June 22, 2001
    Publication date: August 8, 2002
    Inventors: Thomas J. Ford, Patrick C. Fenton, James O. McGuffin, Stanley K. Honey
  • Publication number: 20010035840
    Abstract: Multiple geographically fixed reference stations, with precisely known locations, that each receive GPS signals send information to a central processing facility that generates a three dimension topographical gradient map or model of the differences between the known locations and the locations as calculated from the received GPS signals. GPS signals received by mobile users are communicated to the central processing facility whereupon the central processing facility, using the model, generates precise corrected locations of the mobile users which is sent back to the mobile users. The mobile users can use and display the locally generated position from the locally received GPS signals or the corrected position from the central processing facility.
    Type: Application
    Filed: May 7, 2001
    Publication date: November 1, 2001
    Inventors: Patrick C. Fenton, Graham Purves, Douglas Reid
  • Publication number: 20010026239
    Abstract: A time signal generation system produces a reference time signal based on the signals transmitted by geostationary satellites, such as the satellites in the Wide Area Augmentation System (WAAS). A receiver in the system includes a directional antenna that is focused on the signals transmitted by the geostationary satellite. The antenna rejects multipath signals, and the receiver thus tracks the satellite signal directly, without having to compensate for multipath distortion. Once the receiver is tracking the code and carrier, the receiver decodes the transmitted data to recover timing information, as well as satellite orbital correction information and an ionospheric model, or table, transmitted by the satellite. The receiver then uses the decoded information and timing pulses provided in synchronism with the transmitted PRN code to produce a corrected timing signal.
    Type: Application
    Filed: January 26, 2001
    Publication date: October 4, 2001
    Inventor: Patrick C. Fenton