Anisotropic constitutive parameters for launching a Zenneck surface wave

Patent metadata

Field	Value
Publication number	US-11340275-B2
Application number	US-201916708048-A
Country	US
Kind code	B2
Filing date	Dec 9, 2019
Priority date	Dec 9, 2019
Publication date	May 24, 2022
Grant date	May 24, 2022

Abstract

Various examples are provided related to anisotropic constitutive parameters (ACPs) that can be used to launch Zenneck surface waves. In one example, among others, an ACP system includes an array of ACP elements distributed over a medium such as, e.g., a terrestrial medium. The array of ACP elements can include one or more horizontal layers of radial resistive artificial anisotropic dielectric (RRAAD) elements positioned in one or more orientations over the terrestrial medium. The ACP system can include vertical lossless artificial anisotropic dielectric (VLAAD) elements distributed over the terrestrial medium in a third orientation perpendicular to the horizontal layer or layers. The ACP system can also include horizontal artificial anisotropic magnetic permeability (HAAMP) elements distributed over the terrestrial medium. The array of ACP elements can be distributed about a launching structure, which can excite the ACP system with an electromagnetic field to launch a Zenneck surface wave.

First claim

Therefore, at least the following is claimed:

1. An anisotropic constitutive parameter (ACP) system, comprising:
a launching transducer or a receiving transducer; and
an array of ACP elements distributed over a terrestrial medium about the launching transducer or the receiving transducer, the array of ACP elements comprising:
a first plurality of radial resistive artificial anisotropic dielectric (RRAAD) elements positioned over the terrestrial medium, the first plurality of RRAAD elements comprising one or more series of interconnected RRAAD elements extending in a first orientation, wherein the first plurality of the RRAAD elements forms a horizontal layer at a height over the terrestrial medium.

2. The ACP system of claim 1 , wherein the array of ACP elements is a cylindrical array with each of the one or more series of interconnected RRAAD elements linearly oriented in a ρ-direction.

3. The ACP system of claim 1 , wherein the array of ACP elements comprises a second horizontal layer of RRAAD elements positioned over, and substantially parallel to, the horizontal layer of RRAAD elements distributed at the height over the terrestrial medium, the second horizontal layer of RRAAD elements comprising:
a second plurality of RRAAD elements positioned over the first plurality of RRAAD elements in the horizontal layer, the second plurality of RRAAD elements comprising one or more series of interconnected RRAAD elements extending in the first orientation.

4. The ACP system of claim 1 , wherein the array of ACP elements comprises a second plurality of RRAAD elements positioned over the terrestrial medium, the second plurality of RRAAD elements comprising one or more series of interconnected RRAAD elements extending in a second orientation with respect to the first orientation, wherein the first plurality of the RRAAD elements and the second plurality of the RRAAD elements form the horizontal layer at the height over the terrestrial medium.

5. The ACP system of claim 4 , wherein individual RRAAD element series of the one or more series of interconnected RRAAD elements of the first plurality of RRAAD elements comprises a plurality of RRAAD elements coupled in series by wires extending in the first orientation, and individual RRAAD element series of the one or more series of interconnected RRAAD elements of the second plurality of RRAAD elements comprises a plurality of RRAAD elements coupled in series by wires extending in the second orientation.

6. The ACP system of claim 4 , wherein RRAAD elements of the one or more series of interconnected RRAAD elements of the first plurality of RRAAD elements and the one or more series of interconnected RRAAD elements of the second plurality of RRAAD elements are separated from adjacent elements in that series by a defined distance.

7. The ACP system of claim 6 , wherein the defined distance is a fraction of a wavelength (λ 0 ) of an electromagnetic excitation applied to the ACP system.

8. The ACP system of claim 7 , wherein the defined distance is less than or equal to λ 0 /10.

9. The ACP system of claim 7 , wherein the height of the horizontal layer over the terrestrial medium is a fraction of the wavelength (λ 0 ).

10. The ACP system of claim 4 , wherein the array of ACP elements is a rectangular array with the one or more series of interconnected RRAAD elements of the first plurality of RRAAD elements linearly oriented in an x-direction and the one or more series of interconnected RRAAD elements of the second plurality of RRAAD elements linearly oriented in a y-direction substantially perpendicular to the x-direction.

11. The ACP system of claim 10 , wherein an overall dimension of the rectangular array of RRAAD elements is λ 0 ×λ 0 .

12. The ACP system of claim 11 , wherein the rectangular array of RRAAD elements does not include RRAAD elements at corners of the rectangular array.

13. The ACP system of claim 11 , wherein each individual RRAAD element of the first plurality of RRAAD elements is collocated with a corresponding individual RRAAD element of the second plurality of RRAAD elements.

14. The ACP system of claim 13 , wherein the individual RRAAD element of the first plurality of RRAAD elements and the corresponding individual RRAAD element of the second plurality of RRAAD elements are implemented on a common substrate.

15. The ACP system of claim 14 , wherein the individual RRAAD element of the first plurality of RRAAD elements comprises a first capacitor and a first resistor mounted on a first side of a printed circuit board (PCB) and the corresponding individual RRAAD element of the second plurality of RRAAD elements comprises a second capacitor and a second resistor mounted on a second side of the PCB.

16. The ACP system of claim 4 , the array of ACP elements comprises a second horizontal layer of RRAAD elements positioned over, and substantially parallel to, the horizontal layer of RRAAD elements distributed at the height over the terrestrial medium, the second horizontal layer of RRAAD elements comprising:
a third plurality of RRAAD elements positioned over the first plurality of RRAAD elements in the horizontal layer, the third plurality of RRAAD elements comprising one or more series of interconnected RRAAD elements extending in the first orientation; and
a fourth plurality of RRAAD elements positioned over the second plurality of RRAAD elements in the horizontal layer, the fourth plurality of RRAAD elements comprising one or more series of interconnected RRAAD elements extending in the second orientation.

17. The ACP system of claim 16 , wherein each RRAAD element series of the one or more series of interconnected RRAAD elements of the third plurality of RRAAD elements is substantially aligned with a corresponding RRAAD element series of the one or more series of interconnected RRAAD elements of the first plurality of RRAAD elements, and each RRAAD element series of the one or more series of interconnected RRAAD elements of the fourth plurality of RRAAD elements is substantially aligned with a corresponding RRAAD element series of the one or more series of interconnected RRAAD elements of the second plurality of RRAAD elements.

18. The ACP system of claim 16 , wherein the second horizontal layer of RRAAD elements is separated from the horizontal layer of RRAAD elements by a fraction of a wavelength (λ 0 ) of an electromagnetic excitation applied to the ACP system.

19. The ACP system of claim 18 , wherein the separation between the second horizontal layer of RRAAD elements and the horizontal layer or RRAAD elements is about twice the height of the horizontal layer of RRAAD elements.

20. The ACP system of claim 1 , wherein the launching transducer is configured to excite the ACP system with an electromagnetic field at a frequency (f 0 ).

21. The ACP system of claim 20 , wherein the array of ACP elements is distributed about one side of the launching transducer.

22. The ACP system of claim 1 , wherein individual RRAAD elements of the array of ACP elements comprise a capacitor and a resistor connected in parallel, the capacitor and resistor comprising one or more lumped element components.

23. The ACP system of claim 22 , wherein the capacitor comprises a variable capacitance, the resistor comprises a variable resistance, or both.

24. The ACP system of claim 1 , wherein the array of ACP elements comprises a plurality of vertical lossless artificial anisotropic dielectric (VLAAD) elements distributed

Assignees

• Cpg Technologies Llc

Inventors

• Jean Buford Randall
• Lilly James D
• Tinlin Benjamin J

Classifications

• H02J50/20

  using microwaves or radio frequency waves · CPC title

• G01V3/38

  Processing data, e.g. for analysis, for interpretation, for correction · CPC title

• G01V3/12 Primary

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

• G01R27/2676

  Probes · CPC title

• G01R27/18

  Measuring resistance to earth {, i.e. line to ground} · CPC title