MEANDER-LINE RING RESONATOR

• US 20130181725A1
• Filed: 11/01/2012
• Published: 07/18/2013
• Est. Priority Date: 01/13/2012
• Status: Active Grant

• Current Assignee: United States Secretary of the Army
• Original Assignee: US Army Research Laboratory (Government of the United States of America)
• Inventors: Mazzaro, Gregory J.
• Granted Patent: US 9,151,787 B2
• Time in Patent Office: Days
• US Class Current: 324/636
• CPC Class Codes: G01R 27/04 in circuits having distributed constants , e.g. having very long conductors or involving high frequencies
• CPC Class Codes: G01R 27/2623 Measuring-systems or electronic circuits G01R27/2635, G01R27/2682 take precedence
• CPC Class Codes: H01P 7/00 Resonators of the waveguide type
• CPC Class Codes: H01P 7/082 Microstripline resonators H01P7/088 takes precedence

Abstract

Methods and apparatus for measuring permittivity comprising: a meander-line ring resonator, which may be may be disposed on a substrate proximate to and separated from an input coupler and an output coupler thereon, the resonator ring further including a continuous conductive material having at least two turns to form a single congruent pattern, symmetrical along at least one axis.

Claims

1. An apparatus for measuring permittivity comprising:

a meander-line ring resonator, proximate to and separated from an input coupler and an output coupler, the ring further comprising a continuous conductive material having at least two turns to form a single congruent pattern, symmetrical along at least one axis.

2. The apparatus of claim 1, further comprising:

the input coupler positioned on a side of the resonator, the input coupler elongated to conform to the side of the resonator; and

the output coupler positioned on an opposite side of the resonator, the output coupler elongated to conform to the opposite side of the resonator.

3. The apparatus of claim 1, wherein the at least two turns further comprise at least one pair of arcuate portions and at least one pair of serpentine portions.

4. The apparatus of claim 3, wherein the input coupler and output coupler are arcuate and are substantially parallel, spaced apart from the arcuate portions of the ring resonator.

5. The apparatus of claim 2, wherein the serpentine portions further comprise at least three continuous symmetrical turns along the at least one axis.

6. The apparatus of claim 2, wherein the input coupler and output coupler is comprised of a curved length that is a substantial percentage of the resonator.

7. The apparatus of claim 1, wherein the resonator is configured to resonate at a frequency below 1 GHz.

8. A meander-line ring resonator comprising:

a continuous conductive material having at least two turns to form a single congruent pattern, symmetrical along at least one axis.

9. A method for measuring a change in the electric field comprising:

capacitively coupling a radio-frequency (RF) signal from an input coupler across a first gap to a meander-line ring, where the meander-line ring is continuous conductive material on the substrate with at least two turns to form a single congruent pattern symmetrical along at least one axis;

resonating the RF signal within the meander-line ring resonator; and

capacitively coupling the RF signal to the output coupler across a second gap to the meander-line ring resonator.

10. The method of claim 9, further comprising:

receiving the RF signal using an input line connected to the input coupler on a side of the ring, the input coupler being elongated to conform to the side of the ring; and

outputting the RF signal using an output line connected to the output coupler on a opposite side of the ring, the output coupler being elongated to conform to the opposite side of the ring.

11. The method of claim 9, wherein the turns comprise at least one pair of arcuate portions and at least one pair of serpentine portions.

12. The method of claim 9, wherein the input coupler and output coupler are comprised of a curved length that is a substantial percentage of the resonator.

13. The method of claim 9, wherein the meander-line ring resonator further comprises at least three continuous symmetrical turns along at least one axis.

14. The method of claim 9, wherein the meander-line ring resonator resonates at a frequency below 1 GHz.

15. The method of claim 9, further comprising:

storing the signal in memory; and

subsequently positioning a dielectric sample proximate the meander-line ring resonator to generate a change in the frequency response of the meander-line ring resonator.

16. The method of claim 15, further comprising:

comparing the frequency response change with the previously stored data signal of the meander-line ring resonator when no dielectric sample was applied to determine permittivity.

17. A system for providing a portable permittivity measurement comprising:

a substrate;

an input coupler and an output coupler;

the input coupler positioned separate from and opposite to an output coupler on the substrate;

a meander-line ring resonator, proximate to and separated from the input coupler and the output coupler, the ring further comprising a continuous conductive material having at least two turns to form a single congruent pattern, symmetrical along at least one axis; and

a portable computer coupled to the meandering-line ring resonator, wherein the portable computer is configured to send a radio-frequency (RF) signal to the input coupler and to receive a RF signal from the output coupler.

18. The system of claim 17, further comprising:

memory configured to store the signal and a dielectric sample positioned proximate the meander-line ring resonator configured to generate a change in the frequency response of the meander-line ring resonator.

19. The system of claim 18, further comprising:

a microprocessor configured to compare the frequency response change with the previously stored signal of the meander-line ring resonator when no dielectric sample was applied to determine permittivity.