MEMS resonator-based signal modulation
AssigneeDiscera, Inc.
InventorsAndrew R. Brown, Wan-Thai Hsu, Kenneth R. Cioffi, Didier Lacroix
Life of this patent
Estimating the term…
Abstract
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.
Claims21
A signal generator for communication of an information stream, the signal generator comprising:
- a MEMS resonator comprising a resonant structure, a drive electrode and a sense electrode and configured for activation by a DC bias voltage applied to the resonant structure and development of a resonator signal at the sense electrode having a resonant frequency determined by the DC bias voltage in response to an excitation signal applied to the drive electrode, wherein the resonant structure is spaced from the drive electrode by a gap;
- an oscillator circuit coupled to the MEMS resonator across the sense and drive electrodes to apply the excitation signal to the drive electrode to facilitate oscillation of the resonator signal and for generation of an output signal with a frequency based on the resonant frequency of the resonator signal;
- and,
- a port to receive a control signal representative of the information stream, the port being coupled to the MEMS resonator to modulate the DC bias voltage in accordance with the control signal such that the MEMS resonator is biased with the modulated DC bias voltage and both the resonant frequency and the frequency of the output signal are modulated to reflect the information stream.
A signal generator comprising:
- a MEMS resonator configured for activation by a bias voltage and development of a resonator signal having a resonant frequency determined by the bias voltage;
- an oscillator circuit coupled to the MEMS resonator to facilitate oscillation of the resonator signal and generation of an output signal based on the resonator signal;
- a port coupled to the MEMS resonator to receive a control signal from which the bias voltage is determined such that the output signal is modulated by the control signal;
- a plurality of MEMS resonators comprising the first-named MEMS resonator;
- and
- a switch coupling the plurality of MEMS resonators and the port to selectively provide the bias voltage in accordance with the control signal.
A method of generation of a communication signal with a MEMS resonator having a resonant frequency determined by a DC bias voltage for transmission of an information stream provided by a control signal, the method comprising the steps of:
- receiving the control signal;
- modulating the DC bias voltage in accordance with the control signal;
- biasing the MEMS resonator with the modulated DC bias voltage by applying the modulated DC bias voltage to a resonant structure of the MEMS resonator;
- and,
- driving the MEMS resonator with an excitation signal from an oscillator across sense and drive electrodes of the MEMS resonator during the biasing step to generate the communication signal such that both the resonant frequency and a frequency of the communication signal reflect the information stream provided by the control signal;
- wherein the resonant structure is spaced from the drive electrode by a gap.
A method of generation of a communication signal for transmission of information carried by a control signal, the method comprising the steps of:
- receiving the control signal;
- activating a MEMS resonator via a bias voltage;
- determining the bias voltage in accordance with the control signal;
- and
- driving the MEMS resonator for the generation of the communication signal and the transmission of the information carried by the control signal;
- wherein the determining step comprises providing the control signal to a switch to direct the control signal to a plurality of MEMS resonators for selected activation thereof in accordance with the information.
A device to generate a communication signal for transmission of an information stream, comprising:
- a data input to provide an input voltage indicative of the information stream;
- a MEMS resonator comprising a drive electrode, a resonant structure spaced from the drive electrode by a gap, and a sense electrode at which an output signal with a frequency is developed based on a bias voltage applied to the resonant structure and determinative of a resonant frequency of the MEMS resonator wherein the resonant structure is coupled to the data input such that the bias voltage is modulated in accordance with the input voltage and the resonant structure is biased with the modulated bias voltage such that the resonant frequency of the MEMS resonator and the output signal frequency reflect the information stream;
- an oscillator circuit coupled to the MEMS resonator across the sense and drive electrodes to apply a drive signal to the drive electrode to excite the resonant structure into resonance and to develop an oscillator signal based on the output signal frequency of the MEMS resonator;
- and,
- a frequency synthesizer coupled to the oscillator circuit to generate the communication signal in accordance with the oscillator signal and the output signal frequency of the MEMS resonator such that a frequency of the communication signal reflects the information stream.
Dependencies are inferred from the claim text.