Method and apparatus for resolving the position and identity of buried conductive bodies

• US 6,529,006 B1
• Filed: 10/31/2001
• Issued: 03/04/2003
• Est. Priority Date: 10/31/2001
• Status: Active Grant

• Current Assignee: Utiliscope Corporation
• Original Assignee: Utiliscope Corporation
• Inventors: Hayes, Paul
• Primary Examiner(s): PATIDAR, JAY M
• Application Number:
  US09/984,755
• Time in Patent Office: 489 Days
• Field of Search: 324/67, 324/326-329, 324/243, 324/263, 324/345
• US Class Current: 324/326
• CPC Class Codes: G01V 3/104 using several coupled or uncoupled coils G01V3/101 takes precedence

Abstract

Both location and identification of a buried or otherwise hidden conductive body is achieved by impressing a known electromagnetic waveform upon the conductive body, using at least one sensor to detect radiation emitted by the conductive body in response to the impressed waveform, locating the source of the emitted waveform based on comparison of the amplitudes of signals received by the at least two sensors, and evaluating the emitted radiation for deviations from the impressed waveform in order to determine the pattern of distortion caused by the conductive body and thereby identify the conductive body.

Claims

1. A system for locating and identifying buried conductive bodies, comprising:

a waveform generator;

a receiver including at least one sensor arranged to detect electromagnetic radiation emitted by a buried conductive body when a waveform generated by said waveform generator is impressed upon said conductive body;

a processing unit and a display;

wherein said waveform is time-duration limited and said processing unit is arranged to enable identification of said conductive body based on deviation of a waveform of said electromagnetic radiation from said original waveform, and

wherein said processing unit is arranged to locate said conductive bodies based on relative amplitudes of said waveform of said electromagnetic radiation detected by said at least one sensor.

2. A system for locating and identifying buried conductive bodies as recited in claim 1, wherein said time-duration limited waveform exhibits abrupt discontinuities.

3. A system for locating and identifying buried conductive bodies as recited in claim 2, wherein said waveform is a square wave.

4. A system for locating and identifying buried conductive bodies as recited in claim 2, wherein said waveform is a square wave ending in an inductive kick.

5. A system for locating and identifying buried conductive bodies as recited in claim 1, further comprising a coupler arranged to directly inject said waveform into said conductive body.

6. A system for locating and identifying buried conductive bodies as recited in claim 5, wherein said coupler is a clamp.

7. A system for locating and identifying buried conductive bodies as recited in claim 1, further comprising an inductive coupling arranged to inject said waveform into said conductive body.

8. A system for locating and identifying buried conductive bodies as recited in claim 7, wherein said inductive coupling is a coil.

9. A system for locating and identifying buried conductive bodies as recited in claim 1, wherein said at least one sensor is a magnetic field sensor.

10. A system for locating and identifying buried conductive bodies as recited in claim 1, wherein said at least one sensor is a broadband antenna.

11. A system for locating and identifying buried conductive bodies as recited in claim 1, wherein said display includes a display of said waveform of said electromagnetic radiation emitted by the buried conductive body.

12. A system for locating and identifying buried conductive bodies as recited in claim 1, wherein said processing unit is arranged to perform a spectral analysis of said electromagnetic radiation emitted by the buried conductive body.

13. A system for locating and identifying buried conductive bodies as recited in claim 1, wherein said processing unit is arranged to determine parameters of a time domain representation of said electromagnetic radiation emitted by said buried conductive body.

14. A method of locating and identifying buried conductive bodies, comprising the steps of:

generating a time-duration limited waveform;

detecting electromagnetic radiation emitted by a buried conductive body when a waveform generated by said waveform generator is impressed upon said conductive body;

identifying said conductive body based on deviation of a waveform of said electromagnetic radiation from said original waveform, and

locating said conductive bodies based on relative amplitudes of said waveform of said electromagnetic radiation.

15. A method of locating and identifying buried conductive bodies as recited in claim 14, wherein said time-duration limited waveform exhibits abrupt discontinuities.

16. A method of locating and identifying buried conductive bodies as recited in claim 14, wherein said waveform is a square wave.

17. A method of locating and identifying buried conductive bodies as recited in claim 14, wherein said waveform is a square wave ending in an inductive kick.

18. A method of locating and identifying buried conductive bodies as recited in claim 14, further comprising the step of directly injecting said waveform into said conductive body.

19. A method of locating and identifying buried conductive bodies as recited in claim 14, further comprising the step of inductively injecting said waveform into said conductive body.

20. A method of locating and identifying buried conductive bodies as recited in claim 14, further comprising the step of performing a spectral analysis of said electromagnetic radiation emitted by the buried conductive body.

21. A method of locating and identifying buried conductive bodies as recited in claim 14, further comprising the step of determining parameters of a time domain representation of said electromagnetic radiation emitted by said buried conductive body.