Microelectromechanical resonant circulator

Patent metadata

Field	Value
Publication number	US-10673407-B2
Application number	US-201715812296-A
Country	US
Kind code	B2
Filing date	Nov 14, 2017
Priority date	Nov 14, 2016
Publication date	Jun 2, 2020
Grant date	Jun 2, 2020

Abstract

A microelectromechanical resonant circulator device is providing, having a substrate, and at least three electrical ports supported on the substrate. At least three electromechanical resonator elements are connected with associated switch elements and an associated port. The switch elements are operative to provide commutation over time of the electromechanical resonator elements.

First claim

What is claimed is:

1. A microelectromechanical resonant circulator device comprising:
a substrate, at least three electrical ports supported on the substrate;
at least three electromechanical resonator elements; and
at least three switch elements, each switch element electrically connected between at least one associated electromechanical resonator element of the at least three electromechanical resonator elements and at least one associated port of the at least three electrical ports, the at last three switch elements operative to provide commutation over time of the at least three electromechanical resonator elements.

2. The device of claim 1 , wherein the at least three switch elements are operative to commutate the electromechanical resonator elements over time to form an equivalent resonator network with a resonance frequency or impedance or coupling modulated in time.

3. The device of claim 1 , wherein the at least three switch elements are operative to commutate between at least one of a capacitor and a short circuit, a capacitor and an open circuit, an inductor and a short circuit, an inductor and an open circuit, and a short circuit and an open circuit.

4. The device of claim 1 , wherein at least one switch element of the at least three switch elements comprises a capacitor in parallel with a switch, an inductor in parallel with a switch, a single pole single throw switch, or a single pole double throw switch.

5. The device of claim 1 , wherein the at least three switch elements are operative at a same commutation frequency and shifted in phase or at different commutation frequencies and shifted in phase.

6. The device of claim 1 , wherein the at least three switch elements are operative to provide commutation frequencies ranging from 0.001% to 300% of an operating frequency of the circulator device.

7. The device of claim 1 , wherein the at least three electromechanical resonator elements are operative at a same frequency or at different frequencies.

8. The device of claim 1 , further comprising an inductor disposed in parallel with each of the at least three electromechanical resonator element.

9. The device of claim 1 , wherein the at least three electromechanical resonator elements are connected to a common node.

10. The device of claim 1 , wherein the at least three electromechanical resonator elements are connected in a wye configuration, a delta configuration, a hybrid delta-wye configuration, or a differential configuration.

11. The device of claim 1 , further comprising at least three additional electromechanical resonator elements connected to form a differential configuration with two branches shifted in phase by 180°.

12. The device of claim 1 , wherein each of the at least three electromechanical resonator elements comprises a pair of resonators operative at a same frequency or at different frequencies.

13. The device of claim 12 , wherein the at least three switch elements are operative to commutate between the resonators of each pair of resonators, each pair of resonators commutated at a same modulation frequency and shifted in phase.

14. The device of claim 1 , wherein one or more electromechanical resonators of the at least three electromechanical resonators are disposed to form a filter element at each port of the at least three ports, and the at least three switch elements are operative to commutate the filter elements over time to form equivalent filter networks with frequencies or impedances or coupling modulated in time.

15. The device of claim 1 , wherein at least one of the at least three electromechanical resonator elements comprises a Cross-sectional Lame Mode Resonator, a Contour-Mode Resonator, a Film Bulk Acoustic Resonator, a Surface Acoustic Wave Resonator, a MEMS (microelectromechanical system) Resonator, a NEMS (nanoelectromechanical system) Resonator, a Bulk Acoustic Wave (BAW) Resonator, a Quartz Crystal Resonator, an electromechanical delay line, or a dielectric resonator.

16. The device of claim 1 , wherein at least one of the at least three electromechanical resonator elements comprises:
a piezoelectric layer having a length direction (L), a width direction (W), and a thickness direction (T);
a first conductive layer including at least one first electrode disposed over a top surface of the piezoelectric layer, wherein the top surface extends along the length direction and the width direction; and
a second conductive layer including at least one second electrode disposed over a bottom surface of the piezoelectric layer, wherein the bottom surface extends along the length direction and the width direction;
wherein either a vertical-extensional or lateral-extensional or two-dimensional mode of mechanical vibration is excited in a cross sectional plane of the piezoelectric layer in response to at least one signal provided to the at least one first electrode and/or the at least one second electrode.

17. The device of claim 16 , wherein the vertical-extensional or lateral-extensional or two-dimensional mode of mechanical vibration in a cross sectional plane of the piezoelectric layer is sensed through a piezoelectrically generated charge collected by the at least one first electrode and/or the at least one second electrode.

18. The device of claim 16 , wherein the cross sectional plane extends along the width direction and the thickness direction.

19. The device of claim 16 , wherein a frequency of the vertical-extensional or lateral-extensional or two-dimensional mode of mechanical vibration is dependent on either the width direction or the thickness direction of the resonator structure or both the width direction and the thickness direction of the resonator structure.

20. The device of claim 16 , wherein the piezoelectric layer includes at least one piezoelectric material selected from the group consisting of aluminum nitride, doped aluminum nitride, lithium niobate, lithium tantalate, zinc oxide, gallium nitride, and quartz.

21. The device of claim 1 , wherein at least one of the at least three electromechanical resonator elements has a coupling coefficient k t 2 of at least about 0.01%.

22. The device of claim 1 , wherein at least one of the at least three electromechanical resonator elements has a quality factor Q of at least 10.

23. The device of claim 1 , wherein at least one of the at least three electromechanical resonator elements is suspended from the substrate.

24. The device of claim 1 , wherein at least one of the at least three electromechanical resonator elements is supported on the substrate with anchors located at displacement nodes.

25. The device of claim 24 , wherein displacement at the anchors of at least one electromechanical resonator is near zero.

26. The device of claim 1 , wherein at least one port of the at least three electrical ports is connectable to an antenna.

27. A method of operating the microelectromechanical resonant circulator device of claim 1 , comprising operating the at least three switch elements to commutate the at least three electromechanical resonator elements over time at a determined modulation frequency.

28. A radio transceiver including the microelectromechanical resonant circulator device of claim 1 .

29. A non-reciprocal circuit including the microelectromechanical resonant circulator device of claim 1 .

Assignees

• Univ Northeastern
• Univ Texas

Inventors

• Rinaldi Matteo
• Cassella Cristian
• Alu Andrea
• Sounas Dimitrios
• Kord Ahmed

Classifications

• H03H9/171

  implemented with thin-film techniques, i.e. of the film bulk acoustic resonator [FBAR] type · CPC title

• H03H7/52

  One-way transmission networks, i.e. unilines · CPC title

• H01P1/397

  using non- reciprocal phase shifters (H01P1/393 takes precedence) · CPC title

• H03H9/586

  Means for mounting to a substrate, i.e. means constituting the material interface confining the waves to a volume · CPC title

• H03H9/2405 Primary

  of microelectro-mechanical resonators · CPC title