A transducer includes first and second piezoelectric layers made of corresponding different first and second piezoelectric materials and three or more electrodes, implemented in two or more conductive electrode layers. The first piezoelectric layer is sandwiched between a first pair of electrodes and the second piezoelectric layer is sandwiched between a second pair of electrodes. The first and second pairs of electrodes contain no more than one electrode that is common to both pairs.

A piezoelectric micromechanical resonator includes a supporting beam including a fixed edge that is fixed to a supporting member and a free edge opposite the fixed edge, a piezoelectric sensor including an edge attached to the supporting member, the piezoelectric sensor further including a lower electrode, a piezoelectric unit, and an upper electrode sequentially stacked on a surface of the supporting beam, and a lumped mass provided on the surface of the supporting beam at a side of the supporting beam including the free edge, the upper electrode having a Young's modulus smaller than a Young's modulus of the lower electrode.

An apparatus includes a microelectromechanical system (MEMS) die having a first surface and an opposing second surface. The MEMS die includes a surface-mounted resonator on the first surface and includes a first inductor. The apparatus also includes first and second dies. The first die has a third surface and an opposing fourth surface. The first die is coupled to the MEMS die such that the third surface of the first die faces the first surface of the MEMS die. The first and second surfaces are spaced apart. The first die includes an oscillator circuit and a second inductor. The oscillator circuit is coupled to the second inductor. The second inductor is inductively coupled to the first inductor. The second die is electrically coupled to the first die.

An acoustic wave device includes: a first substrate having a first surface on which an acoustic wave element is located; a second substrate having a second surface on which a functional element is located; a third substrate having a third surface, which faces the first and second surfaces, and a fourth surface being opposite to the third surface, a first metal layer separated from the acoustic wave element and a wiring line in the first substrate and connecting the first and third surfaces; a second metal layer separated from the functional element and a wiring line in the second substrate and connecting the second and third surfaces; a first metal pattern located on the third surface, being in contact with the first and second metal layers, and connecting the first and second metal layers; and a terminal located on the fourth surface and electrically connectable to the first metal pattern.

A signal processing apparatus, being configured for transmitting and receiving coherent parallel optical signals, comprises a transmitter apparatus including a first single soliton micro-resonator device and a modulator device, wherein the first single soliton micro-resonator device is adapted for creating a single soliton providing a first frequency comb, wherein the first frequency comb provides a plurality of equidistant optical carriers with a frequency spacing corresponding to a free spectral range of the first single soliton micro-resonator device, and the modulator device is adapted for modulating the optical carriers according to data to be transmitted, and a receiver apparatus including a coherent receiver device with a plurality of coherent receivers and a local oscillator device providing a plurality of reference optical signals, wherein the coherent receiver device and the local oscillator device are arranged for coherently detecting the transmitted modulated optical carriers, wherein the signal processing apparatus further includes at least one second single soliton micro-resonator device having a free spectral range being equal or approximated to the free spectral range of the first single soliton micro-resonator device and being adapted for creating at least one single soliton providing at least one second frequency comb, wherein the at least one second frequency comb provides at least one of additional optical carriers and the reference optical signals. Furthermore, a signal processing method, including transmitting and receiving coherent parallel optical signals via a communication channel is described.

An acoustic wave force field generator array that uses a plurality of synchronized oscillating emitters system that effectively blocks noise from passing through an acoustic barrier of wave/bubble pattern forms generated by the rapid oscillation of the integrated magnet and emitter system. The movement of the magnets also produces an EM field that generates a current to at least partially power the driver and speaker systems.

Embodiments of the present technology may be directed to wave propagation computing (WPC) device(s), such as an acoustic wave reservoir computing (AWRC) device, that performs computations by random projection. In some embodiments, the AWRC device is used as part of a machine learning system or as part of a more generic signal analysis system. The AWRC device takes in multiple electrical input signals and delivers multiple output signals. It performs computations on these input signals to generate the output signals. It performs the computations using acoustic (or electro-mechanical) components and techniques, rather than using electronic components (such as CMOS logic gates or MOSFET transistors) as is commonly done in digital reservoirs.

Examples of the present invention include unreleased coupled multi-cavity resonators and transmission filters. In some examples, the resonators include resonant cavities coupled by acoustic couplers (ABGCs) and acoustic reflectors (ABRs). These acoustic components enable improved confinement of acoustic modes within the resonator to increase the quality factor (Q) and lower the motional resistance (R.sub.x). A coupled resonator with 5 cavities coupled by 4 ABGCs can achieve a Q of 1095 while a single-cavity resonator of the same device size has a Q of 760. In some examples, the devices can be configured to work as electronic transmission filters in at least two types of filter configurations. In the transmission line filter configuration, the device can include a filter structure in an arrangement (LH).sup.N H (LH).sup.N, defined as a Fabry-Perot Resonator (FPR). In the multi-pole filter configuration, the device can include a filter structure in an arrangement similar to the multi-cavity resonator design.

A passive wireless switch circuit and related apparatus are provided. In examples discussed herein, an apparatus includes a smaller number of voltage circuits configured to control a larger number of microelectromechanical systems (MEMS) switches. The voltage circuits passively generate a number of constant voltages based on a number of radio frequency (RF) signals to collectively identify each of the MEMS switches. A decoder circuit decodes the constant voltages to identify a selected MEMS switch and provides a selected constant voltage higher than a defined threshold voltage to close the selected MEMS switch. As such, it may be possible to eliminate active components and/or circuits from the passive wireless switch circuit, thus helping to reduce leakage and power consumption. It may be further possible to reduce conductive traces between the voltage circuits and the MEMS switches, thus helping to reduce routing complexity and footprint of the apparatus.

A transducer includes first and second piezoelectric layers made of corresponding different first and second piezoelectric materials and three or more electrodes, implemented in two or more conductive electrode layers. The first piezoelectric layer is sandwiched between a first pair of electrodes and the second piezoelectric layer is sandwiched between a second pair of electrodes. The first and second pairs of electrodes contain no more than one electrode that is common to both pairs.