HIGH-EFFICIENCY BROADBAND ANTENNA

• US 20200044350A1
• Filed: 09/18/2019
• Published: 02/06/2020
• Est. Priority Date: 03/15/2013
• Status: Active Grant

• Current Assignee: Phasetek, Inc., Worldwide Antenna Systems, LLC
• Original Assignee: Worldwide Antenna Systems, LLC
• Inventors: GORMAN, Kurt
• Granted Patent: US 10,644,404 B2
• Time in Patent Office: Days
• CPC Class Codes: H01Q 1/1228 on a boom
• CPC Class Codes: H01Q 1/1235 Collapsible supports; Means for erecting a rigid antenna
• CPC Class Codes: H01Q 1/14 for wire or other non-rigid radiating elements
• CPC Class Codes: H01Q 1/36 Structural form of radiating elements, e.g. cone, spiral, umbrella; Particular materials used therewithH01Q1/08, H01Q1/14 take precedence
• CPC Class Codes: H01Q 1/38 formed by a conductive layer on an insulating support patch antennas H01Q9/0407; microstrip dipole antennas H01Q9/065; microstrip slot antennas H01Q13/106; transmission line microstrip antennas H01Q13/206; manufacturing reflecting surfaces using insulating material for supporting the reflecting surface H01Q15/142
• CPC Class Codes: H01Q 1/48 Earthing means; Earth screens; Counterpoises
• CPC Class Codes: H01Q 21/29 Combinations of different interacting antenna units for giving a desired directional characteristic H01Q25/00 takes precedence
• CPC Class Codes: H01Q 5/335 at the feed, e.g. for impedance matching
• CPC Class Codes: H01Q 9/0442 with particular tuning means
• CPC Class Codes: H01Q 9/40 Element having extended radiating surface
• CPC Class Codes: H03H 7/21 providing two or more phase shifted output signals, e.g. n-phase output

Abstract

Techniques for tuning a crossed-field antenna are provided. An example of an antenna system includes a D-plate with a D-plate feed conductor, such that the D-plate is a horizontal conductor raised above and insulated from a ground plane, an E-cylinder with an E-cylinder feed conductor, such that the E-cylinder is a vertical hollow conductive cylinder of smaller diameter than the D-plate, which is mounted concentrically above and insulated from the D-plate, a transmitter tuning circuit configured to receive a signal from a transmitter, an E-cylinder tuning circuit operably coupled to the transmitter tuning circuit and the E-cylinder feed conductor, and a D-plate tuning circuit operably coupled to the transmitter tuning circuit and the D-plate feed conductor.

Claims

1. A method for tuning an antenna system including an E-cylinder and D-plate, wherein the E-cylinder and the D-plate are operably coupled to a tuning network including a transmitter feed tuning circuit, an E-cylinder tuning circuit, and a D-plate tuning circuit, comprising:

estimating an impedance of the E-cylinder;

estimating an impedance of the D-plate;

determining a current ratio to provide approximately equal power to the E-cylinder and the D-plate;

providing a carrier signal to a transmitter input;

setting a reactance of the E-cylinder tuning circuit and a reactance of the D-plate tuning circuit based on the current ratio;

setting a reactance of the transmitter feed tuning circuit if the E-cylinder and the D-plate are receiving approximately equal power at approximately a 90 degree phase difference; and

modifying the reactance of the E-cylinder tuning circuit and the D-plate tuning circuit if the E-cylinder and the D-plate are not receiving approximately equal power at a 90 degree phase difference.

2. The method of claim 1 wherein setting the reactance of the transmitter feed tuning circuit includes determining a combined impedance value of the E-cylinder and the D-plate.

3. The method of claim 1 wherein setting the reactance of the E-cylinder tuning circuit and the reactance of the D-plate tuning circuit includes monitoring an E-cylinder feedline sampling toroid and a D-plate feedline sampling toroid.

4. The method of claim 1 wherein setting the reactance of the transmitter feed tuning circuit includes monitoring a voltage standing wave ratio at the transmitter input.

5. The method of claim 1 further comprising measuring radiation efficiency of the antenna system with one or more field intensity meters.

6. A medium frequency transmitting antenna system, comprising:

a D-plate including a D-plate feed conductor, wherein the D-plate is a horizontal conductor raised above and insulated from a ground plane and a diameter of the D-plate is approximately 0.02 times a wavelength of an operational frequency of the antenna system;

an E-cylinder including an E-cylinder feed conductor, wherein the E-cylinder is a vertical hollow conductive cylinder of smaller diameter than the D-plate, which is mounted concentrically above and insulated from the D-plate and a height of the E-cylinder is approximately 0.035 times the wavelength of the operational frequency of the antenna system;

a transmitter tuning circuit configured to receive a signal from a transmitter;

an E-cylinder tuning circuit operably coupled to the transmitter tuning circuit and the E-cylinder feed conductor; and

a D-plate tuning circuit operably coupled to the transmitter tuning circuit and the D-plate feed conductor;

wherein an E-cylinder tuning circuit reactance and a D-plate tuning circuit reactance are set such that approximately equal power is provided to the E-cylinder and the D-plate, and a transmitter tuning circuit reactance is set based at least in part on the E-cylinder tuning circuit reactance and the D-plate tuning circuit reactance.

7. The medium frequency transmitting antenna system of claim 6 wherein the E-cylinder tuning circuit reactance and the D-plate tuning circuit reactance are set such that a phase difference between an E-cylinder feed signal detected on the E-cylinder feed conductor and a D-plate feed signal detected on the D-plate feed conductor is approximately 90 degrees.

8. The medium frequency transmitting antenna system of claim 6 wherein the transmitter tuning circuit includes a T-network with a first inductor, a second inductor, and a shunt leg including a variable capacitor and a parallel capacitor.

9. The medium frequency transmitting antenna system of claim 8 wherein an inductance value for each of the first inductor and the second inductor is between 1 and 100 microhenries.

10. The medium frequency transmitting antenna system of claim 6 wherein the E-cylinder tuning circuit includes a series inductor and a variable shunt inductor.

11. The medium frequency transmitting antenna system of claim 10 wherein an inductance value for each of the series inductor and the variable shunt inductor is between 1 and 100 microhenries.

12. The medium frequency transmitting antenna system of claim 6 wherein the D-plate tuning circuit 614 includes a series variable inductor with a shunt inductor.

13. The medium frequency transmitting antenna system of claim 12 wherein an inductance value for each of the series variable inductor and the shunt inductor is between 1 and 100 microhenries.

14. A medium frequency transmitting antenna system, comprising:

a D-plate including a D-plate feed conductor, the D-plate having a diameter approximately 0.02 times a wavelength of an operational frequency of the antenna system;

an E-cylinder including an E-cylinder feed conductor, the E-cylinder having a height of approximately 0.035 times the wavelength of the operational frequency of the antenna system;

a transmitter tuning circuit including a T-network with a first inductor, a second inductor, and a shunt leg including a variable capacitor and a parallel capacitor;

an E-cylinder tuning circuit including a series inductor and a variable shunt inductor; and

a D-plate tuning circuit including a series variable inductor with a shunt inductor;

wherein the transmitter tuning circuit is configured to receive a signal from a transmitter, the E-cylinder tuning circuit is operably coupled to the E-cylinder feed conductor and the transmitter tuning circuit, and the D-plate tuning circuit is operably coupled to the D-plate feed conductor and the transmitter tuning circuit.

15. The medium frequency transmitting antenna system of claim 14 wherein an E-cylinder tuning circuit reactance and a D-plate tuning circuit reactance are set such that approximately equal power is provided to the E-cylinder and the D-plate, and a transmitter tuning circuit reactance is set based at least in part on the E-cylinder tuning circuit reactance and the D-plate tuning circuit reactance.

16. The medium frequency transmitting antenna system of claim 15 wherein the E-cylinder tuning circuit reactance and the D-plate tuning circuit reactance are set such that a phase difference between an E-cylinder feed signal detected on the E-cylinder feed conductor and a D-plate feed signal detected on the D-plate feed conductor is approximately 90 degrees.