In accordance with an embodiment, a method of operating an RF system includes generating a first RF signal having a first frequency; filtering the generated first RF signal to form a first filtered transmitted signal; producing a first coupled signal and a first transmitted signal from the first filtered transmitted signal; transmitting the first transmitted signal; transmitting a second RF signal having a second frequency; bandpass filtering the first coupled signal to form a first tunable bandpass filtered signal; and measuring a parameter of the first tunable bandpass filtered signal.

An acoustic transformer in a transmitter chain is disclosed. In one aspect, a differential power amplifier may produce a differential signal that is provided to an acoustic transformer coupled to an acoustic filter. The acoustic transformer provides a single-ended output signal for use by the acoustic filter. To facilitate operation in multiple bands, multiple acoustic transformer-acoustic filter pairs may be provided with a switching network used to route the amplified signal to the appropriate transformer-filter pair.

A surface acoustic wave device comprises a piezoelectric substrate (1), at least one inter-digital transducers (IDT) (2) provided on the piezoelectric substrate, at least one elongated electrode pad (4) electrically connected to the IDT, and at least one stud bump (5) disposed on the electrode pad such that an LC component of the surface acoustic wave device has a predetermined value.

Integrated Microelectromechanical System (MEMS) devices and methods for making the same. The integrated MEMS device comprises a substrate (200) with first electronic circuitry (206) formed thereon, as well as a MEMS filter device (100). The MEMS filter device has a transition portion (118) configured to (a) electrically connect the MEMS filter device to second electronic circuitry and (b) suspend the MEMS filter device over the substrate such that a gas gap exists between the substrate and the MEMS filter device. The transition portion comprises a three dimensional hollow ground structure (120) in which an elongate center conductor (122) is suspended. The RF MEMS filter device also comprises at least two adjacent electronic elements (102/110) which are electrically isolated from each other via a ground structure of the transition portion, and placed in close proximity to each other.

An electrical circuit assembly can include a semiconductor integrated circuit, such as fabricated including CMOS devices. A first lateral-mode resonator can be fabricated upon a surface of the semiconductor integrated circuit, such as including a deposited acoustic energy storage layer including a semiconductor material, a deposited piezoelectric layer acoustically coupled to the deposited acoustic energy storage layer, and a first conductive region electrically coupled to the deposited piezoelectric layer and electrically coupled to the semiconductor integrated circuit. The semiconductor integrated circuit can include one or more transistor structures, such as fabricated prior to fabrication of the lateral-mode resonator. Fabrication of the lateral-mode resonator can include low-temperature processing specified to avoid disrupting operational characteristics of the transistor structures.

An apparatus includes: a substrate; a lid disposed over the substrate, and comprising posts disposed around a perimeter of the substrate, the posts enclosing a cavity between the lid and the substrate; an electronic device disposed over an upper surface of the substrate, and in the cavity; an electrical contact pad; and an electrically insulating layer disposed between the electrical contact pad and an upper surface of the lid.

Several embodiments are disclosed that provide for a frequency selective surface that can be placed like a radome on top of or under an existing radome or as a new radome on top of one or more radiating or receiving apertures or antennas to provide for a high-Q filter function to remove unwanted neighboring frequency interferences. The conformal structure comprises of an array of subwavelength electrically connected broken metallic rings and/or broken wires loaded with electromechanical resonators such as quartz or LiNbO.sub.3 crystal resonators, Bulk Acoustic Wave (BAW) resonators, and/or Surface Acoustic Wave (SAW) resonators at said breaks. When excited by an incident electromagnetic wave this collection of loaded rings and/or wires behaves as a filter which is capable of rejecting and/or passing frequencies over a narrow bandwidth. This medium can be formed into conformal shapes which can be placed over antennas and apertures as a frequency selective material, to introduce these frequency characteristics into the radiation pattern of the antenna, thereby reducing the gain of the antenna very sharply near the outside edges of the intended operating band. By loading the elements of this FSS with capacitors and/or inductors, additional spectral features can be added to the frequency response of the material to introduce broad pass and reject bands, to enable additional design flexibility for shared apertures. These reject or pass bands are significantly more narrow than achievable with traditional LC loaded FSS structures.

Several embodiments are disclosed that provide for a frequency selective surface that can be placed like a radome on top of or under an existing radome or as a new radome on top of one or more radiating or receiving apertures or antennas to provide for a high-Q filter function to remove unwanted neighboring frequency interferences. The conformal structure comprises of an array of subwavelength electrically connected broken metallic rings and/or broken wires loaded with electromechanical resonators such as quartz or LiNbO.sub.3 crystal resonators, Bulk Acoustic Wave (BAW) resonators, and/or Surface Acoustic Wave (SAW) resonators at said breaks. When excited by an incident electromagnetic wave this collection of loaded rings and/or wires behaves as a filter which is capable of rejecting and/or passing frequencies over a narrow bandwidth. This medium can be formed into conformal shapes which can be placed over antennas and apertures as a frequency selective material, to introduce these frequency characteristics into the radiation pattern of the antenna, thereby reducing the gain of the antenna very sharply near the outside edges of the intended operating band. By loading the elements of this FSS with capacitors and/or inductors, additional spectral features can be added to the frequency response of the material to introduce broad pass and reject bands, to enable additional design flexibility for shared apertures. These reject or pass bands are significantly more narrow than achievable with traditional LC loaded FSS structures.

According to various embodiments, there is provided a micro-electromechanical resonator, including a substrate with a cavity therein; and a resonating structure suspended over the cavity, the resonating structure having a first end anchored to the substrate, wherein the resonating structure is configured to flex in a flexural mode along a width direction of the resonating structure, wherein the width direction is defined at least substantially perpendicular to a length direction of the resonating structure, wherein the length direction is defined from the first end to a second end of the resonating structure, wherein the second end opposes the first end.

A resonant circuit includes a resonator. An inductor is connected in parallel with the resonator. An inductor is connected in series with the parallel circuit formed of the resonator and the inductor. Further, a variable capacitor is connected in parallel with a series circuit formed of the inductor and the parallel circuit formed of the resonator and the inductor. The variable capacitor is connected in series with these circuits. As a result, a resonant circuit and a high-frequency filter supporting more communication signals are provided.