Patents Assigned to Radiodetection Limited
  • Patent number: 8742747
    Abstract: A locator for determining the location and/or orientation of a concealed conductor, comprising a reference field detector operable to detect an alternating magnetic field along a reference axis; a first field detector operable to detect an alternating magnetic field along a first axis; and a processor operable to calculate an in-phase component of a signal detected by the first field detector, the in-phase component being in phase with a signal detected at the reference field detector and to calculate a signal indicative of a position of the concealed conductor relative to the locator using at least the in-phase component.
    Type: Grant
    Filed: December 6, 2010
    Date of Patent: June 3, 2014
    Assignee: Radiodetection Limited
    Inventor: Richard David Pearson
  • Patent number: 8676522
    Abstract: A locator for locating a concealed conductor comprises a first field detector operable to detect an alternating magnetic field along a first axis parallel to a primary axis of the locator; a second field detector, displaced from the first field detector and operable to detect an alternating magnetic field along a second axis parallel to the primary axis of the locator; and a processor operable to calculate a difference between a field detected by the first detector and a field detected by the second detector, and to calculate an indication of the lateral displacement of the concealed conductor from the primary axis of the locator using the difference.
    Type: Grant
    Filed: December 6, 2010
    Date of Patent: March 18, 2014
    Assignee: Radiodetection Limited
    Inventor: Richard David Pearson
  • Patent number: 8566043
    Abstract: A detector for calculating the distortion of an electromagnetic field produced by a buried current carrying conductor comprises three antennas B, M, T. Outputs of two pairs of antennas are compared and the depth of the buried conductor is calculated using two different methods. If there is a significant difference in the two calculated depths then it is deemed that the electromagnetic field produced by the buried current carrying conductor is significantly distorted by the material in which the conductor is buried.
    Type: Grant
    Filed: March 2, 2009
    Date of Patent: October 22, 2013
    Assignee: Radiodetection Limited
    Inventors: John Mark Royle, Richard David Pearson
  • Publication number: 20120139525
    Abstract: A locator for determining the location and/or orientation of a concealed conductor, comprising a reference field detector operable to detect an alternating magnetic field along a reference axis; a first field detector operable to detect an alternating magnetic field along a first axis; and a processor operable to calculate an in-phase component of a signal detected by the first field detector, the in-phase component being in phase with a signal detected at the reference field detector and to calculate a signal indicative of a position of the concealed conductor relative to the locator using at least the in-phase component.
    Type: Application
    Filed: December 6, 2010
    Publication date: June 7, 2012
    Applicant: RADIODETECTION LIMITED
    Inventor: Richard David Pearson
  • Publication number: 20120143532
    Abstract: A locator for locating a concealed conductor comprises a first field detector operable to detect an alternating magnetic field along a first axis parallel to a primary axis of the locator; a second field detector, displaced from the first field detector and operable to detect an alternating magnetic field along a second axis parallel to the primary axis of the locator; and a processor operable to calculate a difference between a field detected by the first detector and a field detected by the second detector, and to calculate an indication of the lateral displacement of the concealed conductor from the primary axis of the locator using the difference.
    Type: Application
    Filed: December 6, 2010
    Publication date: June 7, 2012
    Applicant: RADIODETECTION LIMITED
    Inventor: Richard David Pearson
  • Patent number: 8125210
    Abstract: A detector for calculating a depth of a buried conductor is provided. The detector includes a plurality of antennas for detecting an electromagnetic field radiated by the conductor and one or more signal processors for calculating the depth of the conductor based on the field detected by the antennas. The calculated depth of the conductor is displayed when one or more predetermined criteria are satisfied.
    Type: Grant
    Filed: March 2, 2009
    Date of Patent: February 28, 2012
    Assignee: Radiodetection Limited
    Inventors: John Mark Royle, Richard David Pearson
  • Patent number: 8115489
    Abstract: A detector for detecting a buried conductor comprises a plurality of antennas B, T. Each antenna B, T has a winding wound around the antenna, the winding being connected to a current source for providing a predefined current in the winding. When the predefined current is applied to the winding an electromagnetic field is generated at the antenna which induces a test current in the antenna. The test current is compared to calibration data stored in the detector to validate the correct operation of the detector.
    Type: Grant
    Filed: March 2, 2009
    Date of Patent: February 14, 2012
    Assignee: Radiodetection Limited
    Inventors: Richard David Pearson, Kevin Conway
  • Patent number: 8058874
    Abstract: A system for detecting a buried conductor comprises a transmitter for producing an alternating test current in the buried conductor and a receiver for detecting an electromagnetic field produced by the test current in the buried conductor. A communication link is provided between the receiver and the transmitter. The receiver measures the signal to noise ratio, SNR, of the electromagnetic field produced by the test current and if the SNR is below a threshold then the receiver controls the transmitter to set frequency and/or power characteristics of the test current.
    Type: Grant
    Filed: March 2, 2009
    Date of Patent: November 15, 2011
    Assignee: Radiodetection Limited
    Inventors: John Mark Royle, Jeff Thompson
  • Patent number: 7994770
    Abstract: A system for detecting a buried conductor comprises a transmitter for generating a test signal in the buried conductor and a detector for detecting an electromagnetic signal resulting from the test signal flowing in the buried conductor. The transmitter comprises a waveform generator for generating a drive waveform signal, a power supply, an amplifier, connected to the power supply and the waveform generator for producing an output drive signal based on the drive waveform signal and an output circuit for acting on the output drive signal to generate an output signal having a current and a voltage. In-phase and quadrature components of the current and voltage of the output signal are fed back for controlling the amplifier.
    Type: Grant
    Filed: March 2, 2009
    Date of Patent: August 9, 2011
    Assignee: Radiodetection Limited
    Inventors: John Mark Royle, Richard David Pearson
  • Patent number: 7969137
    Abstract: A system for detecting a buried conductor comprises a transmitter for producing an alternating test current in the buried conductor and a receiver for detecting an electromagnetic field produced by the test current in the buried conductor. A communication link is provided between the receiver and the transmitter. The test current comprises first and second components of different frequency. The receiver monitors the phase creepage of the first and second components and controls the transmitter to reset the phase difference between the first and second components as phase creepage increases.
    Type: Grant
    Filed: March 2, 2009
    Date of Patent: June 28, 2011
    Assignee: Radiodetection Limited
    Inventor: John Mark Royle
  • Patent number: 7940056
    Abstract: The present invention provides a method of time domain reflectometry including transmitting a test signal along a cable under test from one end and sensing and recording a reflected signal from the cable at that end, using the recorded, reflected signal to estimate the distance, Ldist, from the one end to a discontinuity on the cable, separating a test signal component from the remainder, Vr, of the reflected signal; estimating the impedance, Zfault, of the discontinuity from known, predetermined values of the characteristic impedance, Zline, and of the characteristic gain, T, of a reference cable, and from the said separated test signal and reflected signal components, calculating the estimation error as a difference between the model reflection signal, Vrmod, expected of the cable under test based on the characteristic impedance and characteristic gain and the estimated impedance, Zfault and distance, Ldist, and the actual reflection signal Vr, choosing new estimated values of Ldist and Zfault in accordance
    Type: Grant
    Filed: March 25, 2009
    Date of Patent: May 10, 2011
    Assignee: Radiodetection Limited
    Inventor: Stephen Maslen
  • Patent number: 7847556
    Abstract: A detector 1 for detecting a buried current carrying conductor comprises a digital homodyne receiver. The receiver processes field strength signals induced in a pair of vertically spaced antennae 3, 5. The analogue to digital converter is an audio-grade stereo CODEC 11.
    Type: Grant
    Filed: June 20, 2006
    Date of Patent: December 7, 2010
    Assignee: Radiodetection Limited
    Inventor: John Mark Royle
  • Publication number: 20100060285
    Abstract: A detector for detecting a buried conductor comprises a plurality of antennas B, T. Each antenna B, T has a winding wound around the antenna, the winding being connected to a current source for providing a predefined current in the winding. When the predefined current is applied to the winding an electromagnetic field is generated at the antenna which induces a test current in the antenna. The test current is compared to calibration data stored in the detector to validate the correct operation of the detector.
    Type: Application
    Filed: March 2, 2009
    Publication date: March 11, 2010
    Applicant: RADIODETECTION LIMITED
    Inventors: Richard David Pearson, Kevin Conway
  • Publication number: 20100001714
    Abstract: A detector for calculating a depth of a buried conductor comprises a plurality of antennas B, M T for detecting an electromagnetic field radiated by the conductor and means for calculating the depth of said conductor based on the field detected by the antennas B, M, T. The calculated depth of the conductor is displayed when one or more predetermined criteria are satisfied.
    Type: Application
    Filed: March 2, 2009
    Publication date: January 7, 2010
    Applicant: RADIODETECTION LIMITED
    Inventor: John Mark Royle
  • Publication number: 20100001732
    Abstract: A detector for calculating a depth of a buried conductor comprises three parallel antennas B, M, T. The second antenna M is spaced a distance s from the first antenna B and the third antenna T is a distance 2s from the first antenna B and a distance s from the second antenna M. The outputs of the first and second antennas B, M are compared and the outputs from the second and third antennas M, T are compared. The depth of the buried conductor is calculated based on the first and second compared values.
    Type: Application
    Filed: March 2, 2009
    Publication date: January 7, 2010
    Applicant: RADIODETECTION LIMITED
    Inventors: John Mark Royle, Richard David Pearson
  • Publication number: 20100001713
    Abstract: A system for detecting a buried conductor comprises a transmitter for producing an alternating test current in the buried conductor and a receiver for detecting an electromagnetic field produced by the test current in the buried conductor. A communication link is provided between the receiver and the transmitter. The test current comprises first and second components of different frequency. The receiver monitors the phase creepage of the first and second components and controls the transmitter to reset the phase difference between the first and second components as phase creepage increases.
    Type: Application
    Filed: March 2, 2009
    Publication date: January 7, 2010
    Applicant: RADIODETECTION LIMITED
    Inventor: John Mark Royle
  • Publication number: 20100001731
    Abstract: A system for detecting a buried conductor comprises a transmitter for generating a test signal in the buried conductor and a detector for detecting an electromagnetic signal resulting from the test signal flowing in the buried conductor. The transmitter comprises a waveform generator for generating a drive waveform signal, a power supply, an amplifier, connected to the power supply and the waveform generator for producing an output drive signal based on the drive waveform signal and an output circuit for acting on the output drive signal to generate an output signal having a current and a voltage. In-phase and quadrature components of the current and voltage of the output signal are fed back for controlling the amplifier.
    Type: Application
    Filed: March 2, 2009
    Publication date: January 7, 2010
    Applicant: RADIODETECTION LIMITED
    Inventors: John Mark Royle, Richard David Pearson
  • Patent number: D610621
    Type: Grant
    Filed: July 3, 2008
    Date of Patent: February 23, 2010
    Assignee: Radiodetection Limited
    Inventor: Denise Louise Harris
  • Patent number: D631893
    Type: Grant
    Filed: July 3, 2008
    Date of Patent: February 1, 2011
    Assignee: Radiodetection Limited
    Inventors: Richard Frederick George Ward, Denise Louise Harris
  • Patent number: D648742
    Type: Grant
    Filed: December 21, 2010
    Date of Patent: November 15, 2011
    Assignee: Radiodetection Limited
    Inventors: Richard Frederick George Ward, Denise Louise Harris