A rotation sensor, including: (i) a substrate having a top surface and an interior bottom surface; (ii) an electrode module positioned on the top surface of the substrate and including a first set of electrodes configured to generate a bulk acoustic wave directly into the substrate, wherein at least a portion of the bulk acoustic wave is transduced into a shear wave upon reflection on the interior bottom surface of the substrate without use of a reflector, and a second set of electrodes configured to detect the shear wave; and (iii) a controller in communication with the first set and second set of electrodes and configured to determine, based on the detected shear wave, an effect of Coriolis force on the sensor.

An Acousto-Optic Gyroscope (AOG) consisting of a photonic integrated device embedded into two inherently matched piezoelectric surface acoustic wave (SAW) resonators sharing the same acoustic cavity is disclosed. The micromachined strain-based AOG uses the effective index of the optical waveguide due to the acousto-optic effect rather than conventional displacement sensing.

An Acousto-Optic Gyroscope (AOG) consisting of a photonic integrated device embedded into two inherently matched piezoelectric surface acoustic wave (SAW) resonators sharing the same acoustic cavity is disclosed. The micromachined strain-based AOG uses the effective index of the optical waveguide due to the acousto-optic effect rather than conventional displacement sensing.

An aspect of the present disclosure concerns an oscillator circuit including a driver circuit that includes a first amplifier and a current detector where the first amplifier produces an oscillation voltage signal, where the current detector detects an oscillation current signal and produces a drive voltage signal, and where the oscillation current signal corresponds to difference in voltage between the oscillation voltage signal and the drive voltage signal; a feedback circuit that includes a second amplifier receiving the oscillation voltage signal and the drive voltage signal, to produce a feedback voltage signal to the driver circuit; and an oscillator that oscillates at a frequency determined in accordance with the drive voltage signal.

An aspect of the present disclosure concerns an oscillator circuit including a driver circuit that includes a first amplifier and a current detector where the first amplifier produces an oscillation voltage signal, where the current detector detects an oscillation current signal and produces a drive voltage signal, and where the oscillation current signal corresponds to difference in voltage between the oscillation voltage signal and the drive voltage signal; a feedback circuit that includes a second amplifier receiving the oscillation voltage signal and the drive voltage signal, to produce a feedback voltage signal to the driver circuit; and an oscillator that oscillates at a frequency determined in accordance with the drive voltage signal.

An aspect of the present disclosure concerns a calibration system including a test tone signal generator that produces a test tone; a transimpedance amplifier (TIA) that comprises two input terminals, receives two output signals from an external sensor device, the test tone, and a calibration signal at the two input terminals, and produces a voltage signal; and a calibration circuit that receives the voltage signal and the test tone to produce the calibration signal that causes the TIA to produce the voltage signal such that an error signal included in the voltage signal is canceled. The external sensor device may be a mode-matched vibratory micro-electro-mechanical systems (MEMS) gyroscope.

A microelectromechanical resonator includes a resonator member suspended over a surface of a substrate by at least one anchor that is connected to the substrate. The resonator member includes outer and inner frames that are concentrically arranged and mechanically coupled by support structures extending therebetween. Related apparatus and gyroscopes are also discussed.

A microelectromechanical resonator includes a resonator member suspended over a surface of a substrate by at least one anchor that is connected to the substrate. The resonator member includes outer and inner frames that are concentrically arranged and mechanically coupled by support structures extending therebetween. Related apparatus and gyroscopes are also discussed.

A bulk acoustic wave resonator apparatus includes a resonator member having an annulus shape, and at least one anchor structure coupling the resonator member to a substrate. A perimeter of the resonator member is at least partially defined by respective sidewalls that are slanted at an angle relative to a plane defined by a surface of the resonator member. The surface of the resonator member may be defined by a (100) crystal plane, and the angle of the respective sidewalls may be defined by a (111) crystal plane. Related fabrication methods are also discussed.

A bulk acoustic wave resonator apparatus includes a resonator member having an annulus shape, and at least one anchor structure coupling the resonator member to a substrate. A perimeter of the resonator member is at least partially defined by respective sidewalls that are slanted at an angle relative to a plane defined by a surface of the resonator member. The surface of the resonator member may be defined by a (100) crystal plane, and the angle of the respective sidewalls may be defined by a (111) crystal plane. Related fabrication methods are also discussed.