HIGH EFFICIENCY POLARIZED ULF/VLF/RF TRANSCIEVER ANTENNA

• US 20150207232A1
• Filed: 01/16/2015
• Published: 07/23/2015
• Est. Priority Date: 01/20/2014
• Status: Active Grant

• Current Assignee: Raytheon Company (Rtx Corporation)
• Original Assignee: Raytheon Company (Rtx Corporation)
• Inventors: Dolgin, Benjamin P.
• Granted Patent: US 9,831,925 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: H01Q 21/245 provided with means for varying the polarisation polarising devices H01Q15/24; tracking by comparing linear polarisation compounds G01S3/146; reducing depolarisation effects H04B7/00; polarisation diversity H04B7/10
• CPC Class Codes: H01Q 3/34 by electrical means active lenses or reflecting arrays H01Q3/46
• CPC Class Codes: H01Q 7/06 with core of ferromagnetic material H01Q7/02 takes precedence
• CPC Class Codes: H01Q 7/08 Ferrite rod or like elongated core
• CPC Class Codes: H04B 1/0475 with means for limiting noise, interference or distortion H04B1/0483 takes precedence
• CPC Class Codes: H04B 5/26 using coils
• CPC Class Codes: H04B 5/263 Multiple coils at either side
• CPC Class Codes: H04B 5/266 One coil at each side, e.g. with primary and secondary coils

Abstract

A transmission antenna includes a closed-loop core having at least two electrically-conductive windings arranged on the closed-loop core. The windings are each electrically-actuated to generate a magnetic flux along the closed-loop core in opposing directions. The transmission antenna may generate a polarized magnetic field within a plane of the closed-loop core and provide broadband transmission of a polarized signal having a relatively flat frequency response. The transmission antenna is electrically-small, and the frequency of the polarized signal is nearly independent of the size of the closed-loop core. Multiple polarized signals may be provided, each being independently and continuously controlled through actuation of the windings. The direction of the polarized signal may also be varied. Additional windings for receiving a signal may simultaneously be employed on the closed-loop core. A method for transmitting a polarized signal with the transmission antenna is also provided.

Claims

1. A transmission antenna comprising:

a closed-loop core;

a first winding having an electrically-conductive wire transversely wound around a first segment of the closed-loop core, the first winding being configured for generating a magnetic flux in a first direction along the closed-loop core when electrical current passes through the first winding; and

a second winding having an electrically-conductive wire transversely wound around a second segment of the closed-loop core, the second winding being configured for generating a magnetic flux in a second direction along the closed loop core when electrical current passes through the second winding;

wherein the magnetic flux in the first direction is opposite the magnetic flux in the second direction for generating a polarized magnetic field and transmitting a polarized signal.

2. The transmission antenna of claim 1, wherein the first winding and the second winding are arranged on the closed-loop core in magnetic symmetry.

3. The transmission antenna of claim 2, wherein the first winding and the second winding are non-overlapping.

4. The transmission antenna of claim 1, wherein the first winding and the second winding each have 50 turns or fewer.

5. The transmission antenna of claim 2,

wherein the first winding is electrically connected in series to the second winding;

wherein the first winding is substantially similar to the second winding; and

wherein the first winding is arranged diametrically opposed to the second winding on the closed-loop core.

6. The transmission antenna of claim 3,

wherein the first winding and the second winding are each helically wound around the closed-loop core;

and

wherein the first winding and the second winding each extend along respective segments of the closed-loop core, the respective segments having a length that is less than 20% of the overall length of the closed-loop core.

7. The transmission antenna of claim 1, wherein the electrically-conductive wire of the respective windings is made from copper or other low-electrical-resistivity material.

8. The transmission antenna of claim 7,

wherein the electrically-conductive wire of the respective windings has a round cross-section with a diameter greater than 0.20 inches;

and

wherein the number of turns of the respective windings is fewer than 20.

9. The transmission antenna of claim 1, wherein the closed-loop core has a cross-sectional area that is at least 50 times greater than the cross-sectional area of the electrically-conductive wire of the respective windings.

10. The transmission antenna of claim 1, wherein the closed-loop core is a toroidal core.

11. The transmission antenna of claim 1, wherein the closed-loop core is made from a ferrite-based material or other high-magnetic permeability material.

12. The transmission antenna of claim 1, further comprising:

a signal conditioner for sending a signal, the signal conditioner being electrically coupled to the first winding and the second winding.

13. The transmission antenna of claim 11, further comprising:

an amplifier electrically interposed between the signal conditioner and the respective windings, the amplifier being configured for amplifying the current of a signal from the signal conditioner.

14. The transmission antenna of claim 1, further comprising:

a third winding having an electrically-conductive wire transversely wound around a third segment of the close-loop core; and

a fourth winding having an electrically-conductive wire transversely wound around a fourth segment of the close-loop core;

wherein the third winding and the fourth winding are each configured for generating a magnetic flux in a direction along the closed-loop core when electrical current passes through the respective third and fourth windings, the respective magnetic fluxes of the third winding and fourth winding being in opposite directions along the closed-loop core for generating a polarized magnetic field;

wherein the first winding and the second winding are configured for generating the polarized signal in a first direction within a plane of the closed-loop core; and

wherein the third winding and the fourth winding are configured for generating a second polarized signal in a second direction within the plane of the closed-loop core.

15. The transmission antenna of claim 12, further comprising:

a third winding and a fourth winding electrically coupled to the signal conditioner;

wherein the third winding is transversely wound with an electrically-conductive wire around a third segment of the close-loop core;

wherein the fourth winding is transversely wound with an electrically-conductive wire around a fourth segment of the close-loop core;

wherein the third winding and the fourth winding are each configured for generating a magnetic flux in a direction along the closed-loop core when electrical current passes through the respective third and fourth windings, the respective magnetic fluxes of the third winding and fourth winding being in opposite directions along the closed-loop core for generating a polarized magnetic field;

wherein the first winding and the second winding are configured for receiving a first electrical signal waveform from the signal conditioner;

wherein the third winding and the fourth winding are configured for receiving a second electrical signal waveform from the signal conditioner; and

wherein the respective windings are configured for generating a polarized signal that is capable of changing direction in response to the phase-shifting between the first electrical signal and the second electrical signal.

16. The transmission antenna of claim 1, further comprising a first receiver winding and a second receiver winding respectively configured for receiving a signal;

wherein the first receiver winding is transversely wound with an electrically-conductive wire around a first receiver segment of the close-loop core, the first receiver winding having a greater number of turns than at least one of the first and second windings used for transmission; and

wherein the second receiver winding is transversely wound with an electrically-conductive wire around a second receiver segment of the close-loop core, the second receiver winding having a greater number of turns than at least one of the first and second windings used for transmission.

17. A method for transmitting a polarized signal from a transmission antenna, comprising the steps:

generating an electrical signal with a signal conditioner;

amplifying the electrical signal with an amplifier to produce an amplified electrical signal;

applying the amplified electrical signal to a first winding having an electrically-conductive wire transversely wound around a first segment of a closed-loop core, and generating a magnetic flux with the first winding that is in a clockwise or counter-clockwise direction along the closed-loop core;

applying the amplified electrical signal to a second winding having an electrically-conductive wire transversely wound around a second segment of the closed-loop core, and generating a magnetic flux with the second winding that is in an opposite direction to the magnetic flux of the first winding;

intersecting the magnetic fluxes from the first and second windings to generate a polarized magnetic field; and

generating a polarized signal that corresponds to the electrical signal, whereby the antenna transmits the polarized signal across a distance.

18. The method according to claim 17, wherein the polarized signal is transmitted with a frequency in the range between 1 Hz and 10 GHz.

19. The method according to claim 17, further comprising the steps:

receiving a signal with a first receiver winding and a second receiver winding, the first and second receiver windings being disposed on respective segments of the closed-loop core, wherein the first and second receiver windings are each transversely wound with an electrically-conductive wire around the close-loop core, the first and second receiver windings each having at least 1,000 turns; and

sending the received signal to the signal conditioner.

20. The method according to claim 17, further comprising the steps:

generating a second electrical signal with the signal conditioner that is phase-shifted from the first-mentioned electrical signal;

amplifying the second electrical signal with the amplifier to produce an amplified second electrical signal;

applying the second amplified electrical signal to a third winding having an electrically-conductive wire transversely wound around a third segment of the closed-loop core, and generating a magnetic flux with the third winding that is in a clockwise or counter-clockwise direction along the closed-loop core;

applying the second amplified electrical signal to a fourth winding having an electrically-conductive wire transversely wound around a fourth segment of the closed-loop core, and generating a magnetic flux with the fourth winding that is in an opposite direction to the magnetic flux of the third winding;

intersecting the magnetic fluxes from the third and fourth windings to generate a second polarized magnetic field;

generating a second polarized signal corresponding to the second electrical signal, and which is phase-shifted from the first polarized signal;

combining the first polarized signal with the second polarized signal to generate a variable polarized signal that is capable of changing direction in response to the phase-shifting between the first and second electrical signals, whereby the antenna transmits the variable polarized signal across a distance.