Method for obtaining underground imagery using a ground-penetrating radar

• US 6,771,206 B2
• Filed: 02/04/2003
• Issued: 08/03/2004
• Est. Priority Date: 12/14/1999
• Status: Expired due to Fees

• Current Assignee: Centre National De La Recherche Scientifique
• Original Assignee: Centre National De La Recherche Scientifique
• Inventors: Berthelier, Jean-Jacques, Meyer, Alain, Ney, Richard
• Primary Examiner(s): Sotomayor, John B.
• Application Number:
  US10/168,351
• Publication Number:
  US 20030132873A1
• Time in Patent Office: 546 Days
• Field of Search: 342/22, 342/27, 342/188, 342/190, 342/191, 324/334, 324/339
• US Class Current: 342/22
• CPC Class Codes: G01S 13/885 for ground probing prospecting or detecting using electromagnetic waves G01V3/12
• CPC Class Codes: G01S 13/89 for mapping or imaging
• CPC Class Codes: G01S 3/143 by vectorial combination of signals derived from differently oriented antennae
• CPC Class Codes: G01S 7/024 using polarisation effects in waveguides H01P1/165; for aerials H01Q, e.g. H01Q15/22, H01Q15/24, H01Q19/195
• CPC Class Codes: G01V 3/12 operating with electromagnetic waves operating with millimetre waves G01V8/005
• CPC Class Codes: G01V 9/02 Determining existence or flow of underground water
• CPC Class Codes: Y02A 90/30 Assessment of water resources

Abstract

A method for using ground-penetrating radar to obtain subsurface imaging. The radar comprises resources for transmitting, receiving and processing signals. In one method embodiment, signals are transmitted from a fixed point relative to the subsurface and with the aid of at least two electrical antennae. Signals reflected or backscattered by reflectors or diffusers of the said subsurface are received by way of the electrical antennae and by way of three magnetic antennae. Finally, the reflected or backscattered signals are processed using an algorithm to obtain the imaging of the said subsurface.

Claims

1. A method of subsurface imaging, using ground-penetrating radar comprising means of transmitting, receiving and processing signals, characterized in that:

signals are transmitted from a fixed point relative to the subsurface and with the aid of at least two electrical antennae;

signals reflected or backscattered by reflectors or diffusers of the said subsurface are received by means of the said electrical antennae and of three magnetic antennae;

and the said reflected or backscattered signals are processed using an algorithm in order to obtain the said imaging of the said subsurface.

2. A method according to claim 1, characterized in that, to determine the distance and direction of the said reflectors or diffusers of the said subsurface, waves that are polarized linearly, circularly or elliptically in a plane are transmitted using the said electrical antennae, and the components of the propagation vector of the reflected or backscattered signals are measured.

3. A method according to claim 2, characterized in that, to obtain waves that are polarized circularly or elliptically in a plane, the said signals are transmitted by means of two or three electrical antennae operating simultaneously with a suitably chosen phase difference between the said transmitted signals.

4. A method according to claim 2, characterized in that, to obtain linearly polarized waves, the said signals are transmitted independently along the respective directions of each of the said electrical antennae.

5. Radar for subsurface imaging, comprising:

at least two electrical antennae used both for the transmission of signals and the reception of signals reflected or backscattered by reflectors or diffusers in the subsurface,

one or more magnetic antennae used for receiving the said reflected or backscattered signals, and

an electronic device for controlling and processing these signals.

6. Radar according to claim 5, characterized in that the said electrical antennae are half-wave dipoles or quarter-wave monopoles.

7. Radar according to claim 5, wherein the said one or more magnetic antennae consist of a single magnetic antenna swivelling in space.

8. Radar according to claim 5, wherein the said one or more magnetic antennae include three magnetic antennae.

9. Radar according to claim 5, wherein the electronic device implements a method of subsurface imaging using ground-penetrating radar, wherein the method is characterized in that:

signals are transmitted from a fixed point relative to the subsurface and with the aid of at leant two electrical antennae;

signals reflected or backscattered by reflectors or diffusers of the said subsurface are received by means of the said electrical antennae and of three magnetic antennae;

and the said reflected or backscattered signals are processed using an algorithm in order to obtain the said imaging of the said subsurface.

10. Radar according to claim 5, characterized in that it is used in the military field for detecting mines or the like.

11. Radar for subsurface imaging, comprising:

at least two electrical antennae used both for the transmission of signals and the reception of signals reflected or backscattered by reflectors or diffusers in the subsurface,

one or more magnetic antennae used for receiving the said reflected or backscattered signals, and

an electronic device for controlling and processing these signals,

wherein the radar is characterized in that it is used in the field of civil engineering for detecting obstacles buried at shallow depths.

12. Radar for subsurface imaging, comprising:

at least two electrical antennae used both for the transmission of signals and the reception of signals reflected or backscattered by reflectors or diffusers in the subsurface,

one or more magnetic antennae used for receiving the said reflected or backscattered signals, and

an electronic device for controlling and processing these signals,

wherein the radar is configured to detect boned pipelines.

13. Radar for subsurface imaging, comprising:

at least two electrical antennae used both for the transmission of signals and the reception of signals reflected or backscattered by reflectors or diffusers in the subsurface,

one or more magnetic antennae used for receiving the said reflected or backscattered signals, and

an electronic device for controlling and processing these signals,

wherein the radar is characterized in that it is used in the field of geology for the exploration of subsurface geological structures.

14. Radar according to claim 13, wherein the radar is configured to detect subsurface resources.