A method for amplitude modulating signals, and a circuit that operates in accordance with the method. The method includes a first step of applying a modulating low frequency signal having a time-varying voltage to a tunable resonator. The tunable resonator exhibits parallel and series resonances at frequencies which shift as a function of the time-varying voltage. A second step includes applying an RF carrier signal having a frequency that is between the parallel resonant frequency and the series resonant frequency to the tunable resonator. In response thereto, the tunable resonator causes the RF carrier signal to be attenuated as a function of the time-varying voltage of the modulating low frequency signal. Also provided is a method for phase modulating signals, and a circuit that operates in accordance therewith. A first step includes applying a modulating low frequency signal having a time-varying voltage to a tunable resonator. The tunable resonator yields a maximum phase shift at one of a parallel resonant frequency and a series resonant frequency in response to the modulating low frequency signal. The amount of phase shift yielded is a function of a variation of the modulating low frequency signal voltage. A further step includes applying an RF carrier signal having a frequency that is substantially equal to the one of a parallel resonant frequency and a series resonant frequency. In response thereto, the tunable resonator phase shifts the RF carrier signal by the amount of phase shift yielded by the tunable resonator.

A device incorporating a tunable thin film bulk acoustic resonator for performing amplitude and phase modulation

A Bulk Acoustic Wave (BAW) filter, comprising at least one resonator structure that is disposed over a substrate, and an acoustic mirror that is disposed over the resonator structure. The acoustic mirror includes a plurality of layers. The acoustic mirror substantially isolates acoustic vibrations produced by the resonator from reaching beyond an upper surface of the acoustic mirror. The acoustic mirror also prevents environmental contaminants from coming into contact with the resonator. Also disclosed are surface-mountable BAW components.

Bulk acoustic wave (BAW) filter having a top portion that includes a protective acoustic mirror

An antenna is provided with an electronic component or circuit that has a value corresponding to properties of the antenna. A read mechanism reads the value and sets an operational status of a transceiver based on the value. In one embodiment, electronic component is a resistor having a value that identifies the antenna properties. A table may be used to correlate resistor values to different types of antennas or sets of antenna properties. Alternatively, the circuit can be embodied in a microchip that provides a response to a challenge sent by the read mechanism. The response encodes the properties of the antenna. The encoding scheme includes values from the challenge. Alternatively, the response is a code that is indexed into a table of antenna properties. In one embodiment, the antenna is connectorized.

Method and apparatus for insuring integrity of a connectorized antenna

There is provided a Bulk Acoustic Wave Resonator-Stacked Crystal Filter (BAWR-SCF) filtering circuit or device. The BAWR-SCF circuit comprises a first pair of ports, a second pair of ports, a first lead that is connected between a first and a second one of the first pair of ports, and a second lead that is connected between a first and a second one of the second pair of ports. The BAWR-SCF circuit also comprises a first BAW resonator connected in series in the first lead, and a second BAW resonator connected between the first and second leads. The BAWR-SCF further comprises a Stacked Crystal Filter (SCF) having first and second terminals connected in the first lead between the first BAW resonator and the second one of the first pair of ports. The SCF also has a third terminal that is connected to a node of the second lead. The frequency response of the BAWR-SCF circuit has steeply-sloped upper and lower edges that are similar to those yielded by ladder filters which are constructed primarily of BAW resonators. The upper and lower notches of the BAWR-SCF circuit's frequency response are also similar to those yielded by ladder filters which are constructed primarily of BAW resonators. The BAWR-SCF circuit also provides stopband attenuation characteristics that are similar to those yielded by SCFs. Additional BAW resonators connected in a ladder configuration and/or SCFs may also be provided in the BAWR-SCF circuit.

Filters and duplexers utilizing thin film stacked crystal filter structures and thin film bulk acoustic wave resonators

A method for tuning a Thin Film Bulk Acoustic Wave Resonator (FBAR) located on a wafer. The FBAR comprises a plurality of layers having respective thicknesses. The FBAR exhibits at least one of a series resonance and a parallel resonance at respective frequencies that are a function of the thickness of at least one of the layers. A first step of the method includes measuring a frequency at which the FBAR exhibits one of a series resonance and a parallel resonance. A next step includes calculating an amount (A) by which the thickness of the at least one layer needs to be altered in order to minimize a difference between the measured frequency and a reference frequency. A further step includes altering the thickness of the at least one layer by the amount (A).

Method for performing on-wafer tuning of thin film bulk acoustic wave resonators (FBARS)

An improved RF shielding integrity monitoring system is provided for monitoring the shielding integrity of a shielded enclosure that accurately identifies degraded shielding effectiveness and leakage areas in the shielded enclosure. The RF shielding integrity monitoring system performs self-testing and self-diagnostic routines to assure proper system operation prior to monitoring of the shielded enclosure. The RF shielding integrity monitoring system includes a transmitter for transmitting predetermined transmitted by the shielded enclosure for receiving the signals; a receiver separated from the transmitted predetermined signals and for identifying the shielding effectiveness of the shielded enclosure; and a cable connected to the transmitter and the receiver for communicating signals between the transmitter and the reciever.

Integrity monitoring method and system for shielded enclosures having a fiber optic cable for bidirectional communications between a receiver and transmitter thereof

A harmonic frequency selecting circuit is provided that simply and effectively provides a desired harmonic frequency output signal and that eliminates the need for frequency multiplier circuits. The harmonic frequency selecting circuit includes an oscillator circuit for generating a fundamental frequency signal and a plurality of harmonic frequency signals of the fundamental frequency signal. A phase modulator circuit is coupled to the oscillator circuit for selectively variably attenuating the generated fundamental and harmonic frequency signals. A bandpass filter circuit is coupled to the phase modulator circuit for selecting a predetermined harmonic frequency output signal.

Dale G. Svetanoff

Papers

Integrity monitoring method and system for shielded enclosures having a fiber optic cable for bidirectional communications between a receiver and transmitter thereof

Harmonic frequency selecting circuit