Electromagnetic receiver tracking and real-time calibration system and method

Patent metadata

Field	Value
Publication number	US-9983326-B2
Application number	US-201514678228-A
Country	US
Kind code	B2
Filing date	Apr 3, 2015
Priority date	Apr 7, 2014
Publication date	May 29, 2018
Grant date	May 29, 2018

Abstract

An electromagnetic (EM) receiver system for measuring EM signals. The EM receiver system includes a survey EM transmitter for generating survey EM signals within a first frequency range; a tracking EM transmitter for generating tracking signals within a second frequency range; and a receiver section including a receiver that measures both the survey EM signals and the tracking signals.

First claim

What is claimed is:

1. An electromagnetic (EM) system for measuring EM signals, the EM system comprising:
a survey EM transmitter for generating survey EM signals within a first frequency range;
a tracking reference frame;
a tracking EM transmitter for generating tracking signals within a second frequency range, wherein the tracking EM transmitter is rigidly attached to the tracking reference frame; and
a receiver section including a receiver housing and a receiver that measures both the survey EM signals and the tracking signals,
wherein the receiver housing is attached with a connecting mechanism to the tracking reference frame so that the receiver housing freely translates and rotates in all directions.

2. The system of claim 1 , further comprising:
a controller connected to the receiver and configured to calculate a position and orientation of the receiver relative to the tracking EM transmitter based on the recorded tracking signals.

3. The system of claim 2 , further comprising:
a global positioning system connected to the controller and configured to provide a location of the tracking EM transmitter relative to ground,
wherein the controller calculates a location and orientation of the receiver relative to ground based on information from the global positioning system and the tracking signals.

4. The system of claim 1 , wherein the first frequency range is different from the second frequency range.

5. The system of claim 1 , wherein the second frequency range is within the first frequency range.

6. The system of claim 1 , wherein the receiver measures the survey EM signals during an OFF-time period and the tracking signals during an ON-time period.

7. The system of claim 1 , wherein the receiver measures the survey EM signals during an entire OFF-time period while measuring the tracking signals during a portion of the OFF-time period.

8. The system of claim 7 , wherein the portion of the OFF-time period is 20% or less than the entire OFF-time period.

9. The system of claim 1 , wherein the receiver section is free to rotate and translate relative to the tracking EM transmitter.

10. The system of claim 1 , wherein a distance between the receiver and the tracking EM transmitter is smaller than a radius of the survey transmitter.

11. The system of claim 1 , wherein the measured tracking signals propagate directly from the tracking EM transmitter to the receivers.

12. An electromagnetic (EM) system for measuring EM signals, the EM system comprising:
an aircraft;
a transmitter section;
a receiver section;
a tracking reference frame; and
a tow assembly connecting the transmitter section and the receiver section to the aircraft,
wherein the transmitter section includes a survey EM transmitter for generating survey EM signals within a first frequency range, and
a tracking EM transmitter for generating tracking signals within a second frequency range, wherein the tracking EM transmitter is rigidly attached to the tracking reference frame; and
wherein the receiver section includes a receiver housing and a receiver that measures both the survey EM signals and the tracking signals, and
wherein the receiver housing is attached with a connecting mechanism to the tracking reference frame so that the receiver housing freely translates and rotates in all directions.

13. The system of claim 12 , further comprising:
a controller connected to the receiver and configured to calculate a position and orientation of the receiver relative to the tracking EM transmitter based on the recorded tracking signals.

14. The system of claim 13 , further comprising:
a global positioning system connected to the controller and configured to provide a location of the tracking EM transmitter relative to ground,
wherein the controller calculates a location and orientation of the receiver relative to ground based on information from the global positioning system and the tracking signals.

15. The system of claim 13 , wherein the receiver measures the survey EM signals during an entire OFF-time period while measuring the tracking signals during a portion of the OFF-time period.

16. A method for determining the position and/or orientation of an electromagnetic (EM) receiver, the method comprising:
crossing a given exploration area with a transmitter section, wherein the transmitter section includes a survey EM transmitter for generating survey EM signals within a first frequency range and a tracking EM transmitter for generating tracking signals within a second frequency range, wherein the tracking EM transmitter is rigidly attached to a tracking reference frame; and
recording with a receiver section including a receiver housing and a receiver, both the survey EM signals and the tracking signals,
wherein the receiver housing is attached with a connecting mechanism to the tracking reference frame so that the receiver housing freely translates and rotates in all directions.

17. The method of claim 16 , further comprising:
calculating in a controller a position and/or orientation of the receiver relative to the tracking EM transmitter based on the recorded tracking signals.

18. The method of claim 17 , further comprising:
receiving from a global positioning system, connected to the controller, a location of the tracking EM transmitter relative to ground; and
calculating a location and orientation of the receiver relative to ground based on the global positioning system and the recorded tracking signals.

19. The method of claim 16 , wherein the measured survey EM signals and the measured tracking signals have different frequencies.

20. The method of claim 16 , wherein the receiver measures the survey EM signals during an entire OFF-time period while measuring the tracking signals during a portion of the OFF-time period.

Assignees

• Cgg Services Sa
• Cgg Services Sas

Inventors

• Miles Philip
• Berringer Jason

Classifications

• G01V3/083

  Controlled source electromagnetic [CSEM] surveying · CPC title

• G01V3/265

  Operating with fields produced by spontaneous potentials, e.g. electrochemicals or produced by telluric currents · CPC title

• G01V3/12

  operating with electromagnetic waves {(operating with millimetre waves G01V8/005)} · CPC title

• G01V3/165 Primary

  operating with magnetic or electric fields produced or modified by the object or by the detecting device (with electromagnetic waves G01V3/17) · CPC title

• G01V3/088

  operating with electric fields (G01V3/082 takes precedence) · CPC title