Discera, Inc.

Wireless Access

Tropian, Inc.

Panasonic Corporation

Kenneth R Cioffi

Earl W McCune

Wan-Thai Hsu

Nigel J Tolson

Didier Lacroix

Andrew Robert Brown

Russell P Prosynchak

Cynthia C Robinson

Michael J Simoneau

Tim A Williams

Sergio A Sanielevici

David S Parkinson

Stephen F Lloyd

Peter O Okrah

A device has a resonator coupled to input and output nodes, the resonator being characterized by a transducer to drive the output node, and further characterized by a feedthrough capacitance such that portions of the input signal bypass the transducer to allow a spurious signal to reach the output node. The device includes a compensation capacitor coupled to the output node to define a compensation capacitance in accordance with the feedthrough capacitance. A phase inversion circuit is coupled to the compensation capacitance to generate a compensation signal and coupled to the output node such that the spurious signal is offset by the compensation signal. In some cases, a differential amplifier of the phase inversion circuit has the compensation capacitance in a feedback path to offset the feedthrough capacitance. In these and other cases, the compensation capacitance and the feedthrough capacitance may be unmatched to avoid overcompensation.

Feedthrough capacitance compensation for resonant devices

Disclosed herein are devices and methods for generating a modulated signal with a MEMS resonator, or microresonator. A bias, or polarization, voltage for activating the MEMS resonator is determined by a control signal, or input voltage, indicative of information to be carried by the modulated signal. In some cases, the MEMS resonator may be driven by an oscillator circuit to facilitate operation of the MEMS resonator. The control signal may include an amplitude modulated voltage or a digital data stream such that output signals of the MEMS resonator or oscillator circuit may carry information via frequency modulation, such as frequency shift keying modulation.

MEMS resonator-based signal modulation

A signal generation technique is based on a reference frequency provided by a MEMS resonator. The signal generation technique compensates for temperature- and fabrication process-induced frequency variations collectively. In some embodiments, a device implementing the disclosed signal generation technique includes a fractional-N synthesizer, a temperature sensor, calibration data, and a sigma-delta modulator to adjust the reference frequency of the MEMS resonator to a desired frequency value while compensating for the temperature variation of the MEMS resonator.

Frequency and temperature compensation synthesis for a MEMS resonator

Disclosed herein is a timing device that includes a resonator device to generate a resonator output signal at a frequency offset from a desired frequency, a counter configured to generate an extraction signal in accordance with the frequency offset, and a timing signal generator configured to track time with a count based on the resonator output signal and modified by the extraction signal downward to reach the desired frequency.

Counter-based resonator frequency compensation

The present invention, generally speaking, uses multiple selectable power supply paths, a saturation detector, or combinations of the same to achieve efficient power supply processing. In one aspect of the invention, a power supply processing circuit includes a first switched converter stage and a second linear stage. Depending on the power supply desired, the first stage may be bypassed to avoid conversion losses. In another aspect of the invention, a saturation detector is used to control the first stage such that the second stage operates efficiently just short of saturation, thereby avoiding distortion.

Power supply processing for power amplifiers

Disclosed herein is a signal generation technique based on a reference frequency provided by a MEMS resonator. The signal generation technique compensates for temperature- and fabrication process-induced frequency variations collectively. In some embodiments, a device implementing the disclosed signal generation technique includes a fractional-N synthesizer, a temperature sensor, calibration data, and a sigma-delta modulator to adjust the reference frequency of the MEMS resonator to a desired frequency value while compensating for the temperature variation of the MEMS resonator.

A multi-level quadrature (I/Q) mixer for use in a communication system such as a paging device, where the mixer includes first and second I/Q downconversions followed by demodulation. The first I/Q downconversion converts an I/Q signal pair to a first IF, and the second I/Q downconversion converts an I/Q signal pair to a second IF. The first IF may or may not be the center frequency depending on the number of subchannels in the single channel being downconverted.

Multi-level mixer architecture for direct conversion of FSK signals

A power generation technique to generate power for use in, for instance, a communication device having a transmitter and a receiver, where communication occurs over atmosphere, or airways (e.g., wireless). The present invention provides a battery-based system that generates power at a high current and high voltage while accommodating the required duty cycles using batteries with sizes that are not prohibitive given the size constraints associated with portable devices in general.

Apparatus for generating power for use in a communications device

An apparatus and method to transmit and receive digital signals in a communication system having a power source that provides power to a portion of a communication device and a mechanism to disable power to that portion of the communication device for periods of time, such that a reduced power consumption state is entered. Also included is sampling hardware to sample the signal during those periods of time when the communication device is not in the reduced power consumption state, which occurs when data is transferred or received.

Method and apparatus for reducing power consumption in digital

A low noise narrow band amplifier with low power consumption for amplifying radio frequency and microwave signals. The amplifier includes a high frequency transistor that has a cut-off frequency greater than the center frequency of the input signal. The amplifier includes an emitter inductor for low noise and better input match. The amplifier is stabilized for out-of-band high frequency oscillations by a collector inductor and a base inductor. The amplifier is further stabilized unconditionally for out-of-band high frequency oscillations by a stabilizing circuit coupled between the output and ground, including a stabilizing capacitor in series with a stabilizing resistor.

Growing community of inventors

San Jose, CA, United States of America

Kenneth R Cioffi