Tuneable electric antenna apparatus including ferroelectric material

• US 5,589,845 A
• Filed: 06/07/1995
• Issued: 12/31/1996
• Est. Priority Date: 12/01/1992
• Status: Expired due to Fees

• Current Assignee: Robert M. Yandrofski, Y. Development, LLC
• Original Assignee: Superconducting Core Technologies, Inc.
• Inventors: Price, John C., Scott, James F., Barnes, Frank, Yandrofski, Robert M., Hermann, Allen M.
• Primary Examiner(s): Hajec, Donald T.
• Assistant Examiner(s): WIGMORE, STEVEN
• Application Number:
  US08/484,012
• Time in Patent Office: 573 Days
• Field of Search: 333/995, 333/161, 343/700 MS, 343/853, 343/909, 343/753, 343/911 R, 342/372, 505/201, 505/210, 505/700, 505/701, 505/866
• US Class Current: 343/909
• CPC Class Codes: H01G 7/06 having a dielectric selected for the variation of its permittivity with applied voltage, i.e. ferroelectric capacitors electrets H01G7/02
• CPC Class Codes: H01P 1/181 using ferroelectric devices
• CPC Class Codes: H01P 7/082 Microstripline resonators H01P7/088 takes precedence
• CPC Class Codes: H01P 7/084 Triplate line resonators H01P7/088 takes precedence
• CPC Class Codes: H01P 7/088 Tunable resonators
• CPC Class Codes: H01Q 1/364 using a particular conducting material, e.g. superconductor
• CPC Class Codes: H01Q 3/44 varying the electric or magnetic characteristics of reflecting, refracting, or diffracting devices associated with the radiating element
• CPC Class Codes: Y10S 505/70 High TC, above 30 k, superconducting device, article, or structured stock
• CPC Class Codes: Y10S 505/701 Coated or thin film device, i.e. active or passive
• CPC Class Codes: Y10S 505/866 Wave transmission line, network, waveguide, or microwave storage device

Abstract

The disclosure relates to ferroelectric and superconducting thin films used in combination to produce low-loss passive microwave and millimeter wave devices which are frequency tuneable. Various metal oxide superconducting and ferroelectric thin films can be deposited in numerous multilayer geometries via a variety of deposition techniques to produce devices which can manipulate microwave and millimeter wave signals through the application of voltage bias signals across the ferroelectric films. Numerous superconducting microwave and millimeter wave devices, including delay lines, phase shifters, resonators, oscillators, filters, electrically-small antennas, half-loop antennas, directional couplers, patch antennas, and various radiative gratings, are made frequency-tuneable by utilizing voltage-tuneable capacitor structures fabricated from voltage-biased ferroelectric thin films. Tuneable antenna arrays are also disclosed incorporating the combined superconducting and ferroelectric thin film structures and geometries which allow for electrical steering of beam patterns by the application of one or more voltage bias signals to ferroelectric thin film gratings.

Claims

1. A tuneable electric antenna apparatus for passing radio frequency energy comprising at least a first tuneable electric antenna component that includes an elongated base portion of a thin film ferroelectric material having a dielectric property, the dielectric property of the ferroelectric material being a function of a voltage applied to the thin film ferroelectric material, a plurality of elements extending from the base portion and spaced apart from one another at a predetermined interval along the length of the base portion, the predetermined interval between each of the plurality of elements providing a predetermined time delay for radio frequency energy, the predetermined time delay between each of the plurality of elements causing the radio frequency energy to be passed at a common predetermined angle with respect to each of the plurality of elements, wherein, when a predetermined voltage is applied to the thin film ferroelectric material, the dielectric property of the thin film ferroelectric material located between each of the plurality of elements changes and the radio frequency energy passes through the thin film ferroelectric material located between each of the plurality of elements to yield said common predetermined angle.

2. A tuneable electric antenna apparatus for passing radio frequency energy in accordance with claim 1 in which the height of each of the plurality of elements being a fraction of the width of the base portion in the direction in which the plurality of elements extend.

3. A tuneable electric antenna apparatus for passing radio frequency energy in accordance with claim 1 in which the radio frequency energy is microwave energy.

4. A tuneable electric antenna component for passing radio frequency energy in accordance with claim 1 in which the dielectric property of the ferroelectric material of the base portion which is a function of a voltage applied to the ferroelectric material is the dielectric constant of the ferroelectric material of the base portion.

5. A tuneable electric antenna apparatus for passing radio frequency energy in accordance with claim 1 in which the plurality of elements extending from the base portion and spaced apart from one another at a predetermined interval along the length of the base portion are of ferroelectric material, the dielectric property of the ferroelectric material is a function of a voltage applied to the ferroelectric material.

6. A tuneable electric antenna apparatus for passing radio frequency energy in accordance with claim 1 and further comprising means for applying said predetermined voltage to the base portion of the ferroelectric material to determine the dielectric property of the antenna apparatus, the means for the dielectric property of the antenna apparatus and the interval between the elements extending from the base portion being adapted to produce the predetermined time delay causing the radio frequency energy to be passed at a common predetermined angle with respect to each of the plurality of elements.

7. A tuneable electric antenna apparatus for passing radio frequency energy in accordance with claim 1 further comprising at least a second tuneable electric antenna component for passing radio frequency energy, said second component having a second elongated base portion of a second thin film ferroelectric material having a second dielectric property, the second dielectric property of the second thin film ferroelectric material being a function of a voltage applied to the second thin film ferroelectric material, a plurality of elements extending from the second elongated base portion and spaced apart from one another at a predetermined interval along the length of the second elongated base portion, the predetermined interval between each of the plurality of elements providing a predetermined time delay for radio frequency energy applied to the second elongated base portion, the predetermined time delay between each of the plurality of elements causing the radio frequency energy to be passed at a common predetermined angle with respect to each of the plurality of elements, each of the first and second components being disposed in a common plane with the base portion thereof positioned parallel to one another with a predetermined distance between each base portion corresponding to an additional predetermined time delay for causing the radio frequency energy to be passed at an additional common predetermined angle with respect to the length of the corresponding base portion of each of the first and second components, and means for applying a biasing voltage to the corresponding base portion of each of the first and second components to control the additional common predetermined angle.

8. A tuneable electric antenna apparatus in accordance with claim 7 and further comprising means for applying a predetermined voltage to cause the radio frequency energy to be passed at a common predetermined angle with respect to each of the plurality of elements of the ferroelectric material and the second ferroelectric material.

9. A tuneable electric antenna apparatus in accordance with claim 7 in which the apparatus includes an additional plurality of tuneable electric antenna components, with the additional plurality of tuneable electric antenna components having the same structure as said first and second components, and in which the means for applying a biasing voltage to the base portion of each of the first and second components applies the biasing voltage to the additional plurality of tuneable electric antenna components.

10. A tuneable electric antenna apparatus for passing radio frequency energy in accordance with claim 1, wherein the thin film ferroelectric material has a thickness and the thickness ranges from 100 to 10,000 angstroms.

11. A tuneable electric antenna apparatus for passing radio frequency energy in accordance with claim 10, wherein the base portion and the plurality of elements are of an integral construction.

12. A tuneable electric antenna apparatus for passing radio frequency energy comprising at least a first tuneable electric antenna component that includes an elongated base portion of a thin film ferroelectric material having a dielectric property, the dielectric property of the thin film ferroelectric material being a function of a voltage applied to the thin film ferroelectric material, a plurality of dielectric elements extending from the base portion and spaced apart from one another at a predetermined interval along the length of the base portion, the predetermined interval between each of the plurality of dielectric elements providing a predetermined time delay for radio frequency energy, the predetermined time delay between each of the plurality of dielectric elements causing the radio frequency energy to be passed at a common predetermined angle with respect to each of the plurality of dielectric elements, wherein, when a predetermined voltage is applied to the base portion, the dielectric property changes to yield the common predetermined angle.

13. A tuneable electric antenna apparatus for passing radio frequency energy in accordance with claim 12 in which the height of each of the plurality of dielectric elements being a fraction of the width of the base portion in the direction in which the plurality of dielectric elements extend.

14. A tuneable electric antenna apparatus for passing radio frequency energy in accordance with claim 12 in which the radio frequency energy is microwave energy.

15. A tuneable electric antenna apparatus for passing radio frequency energy in accordance with claim 12 in which the dielectric property of the thin film ferroelectric material of the base portion which is a function of a voltage applied to the thin film ferroelectric material is the dielectric constant of the thin film ferroelectric material of the base portion.

16. A tuneable electric antenna component for passing radio frequency energy in accordance with claim 12 in which the plurality of dielectric elements extending from the base portion and spaced apart from one another at a predetermined interval along the length of the base portion are of the ferroelectric material.

17. A tuneable electric antenna apparatus for passing radio frequency energy in accordance with claim 12 and further comprising means for applying the predetermined voltage to the base portion of the ferroelectric material to determine the dielectric property of the antenna component, the means for dielectric property of the antenna component and the interval between the dielectric elements extending from the base portion being adapted to produce the predetermined time delay causing the radio frequency energy to be passed at a common predetermined angle with respect to each of the plurality of dielectric elements.

18. A tuneable electric antenna apparatus for passing radio frequency energy in accordance with claim 12 further comprising at least a second tuneable electric antenna component for passing radio frequency energy, said second component having an elongated base portion of a second ferroelectric material having a second dielectric property, the second dielectric property of the second thin film ferroelectric material being a function of a voltage applied to the second thin film ferroelectric material, a plurality of dielectric elements extending from the base portion and spaced apart from one another at a predetermined interval along the length of the base portion, the predetermined interval between each of the plurality of dielectric elements providing a predetermined time delay for radio frequency energy applied to the base portion, the predetermined time delay between each of the plurality of dielectric elements causing the radio frequency energy to be passed at a common predetermined angle with respect to each of the plurality of dielectric elements, each of the first and second components being disposed in a common plane with the base portion thereof positioned parallel to one another with a predetermined distance between each base portion corresponding to an additional predetermined time delay for causing the radio frequency energy to be passed at an additional common predetermined angle with respect to the length of the base portion of each of the first and second components, and means for applying a biasing voltage to the base portion of each of the first and second components to control the additional common predetermined angle.

19. A tuneable electric antenna apparatus in accordance with claim 18 and further comprising means for applying a predetermined voltage to cause the radio frequency energy to be passed at a common predetermined angle with respect to each of the plurality of dielectric elements of each of the first and second components of the antenna apparatus.

20. A tuneable electric antenna apparatus in accordance with claim 18 in which the apparatus includes an additional plurality of tuneable electric antenna components, with the additional plurality of tuneable electric antenna components having the same structure as said first and second components, and in which the means for applying a biasing voltage to the base portion of each of the first and second components applies the biasing voltage to the additional plurality of tuneable electric antenna components.

21. A tuneable electric antenna apparatus for passing radio frequency energy in accordance with claim 12, wherein the thin film ferroelectric material has a thickness and the thickness ranges from 100 to 10,000 angstroms.

22. A method for passing radiation of a selected angular oriented relative to an antenna component, comprising:

applying a voltage to a base portion of an antenna component, the base portion including a thin film ferroelectric material that has a dielectric property, the dielectric property being a function of the voltage applied to the thin film ferroelectric material, the base supporting a plurality of spaced apart elements for passing radiation, with each pair of adjacent elements being separated by a predetermined distance, thereby changing the dielectric property in the thin film ferroelectric material located between the elements; and

passing the radiation through the thin film ferroelectric material located between the elements to provide radiation at a selected angle with respect to each of the plurality of elements, wherein the magnitude of the selected angle is a function of the dielectric property of the thin film ferroelectric material.

23. The method in accordance with claim 22, wherein the thin film ferroelectric material has a thickness ranging from 100 to 10,000 angstroms.

24. The method in accordance with claim 22, further comprising:

applying a second voltage to the base, wherein the second voltage has a different magnitude from the voltage; and

passing the radiation through the thin film ferroelectric material located between the elements to provide radiation at a second selected angle with respect to each of the plurality of elements, wherein the second selected angle has a different magnitude from the selected angle.