Patent ID: 8058940

Claim:
An apparatus, comprising: a resonator body; a driving electrode configured to drive resonation of the resonator body; a sensing electrode configured to sense resonation of the resonator body; a first non-linear mixer coupled to the resonator body, the first non-linear mixer configured to: receive a frequency of a first mixer input signal and a frequency of a local oscillator signal as input frequencies, mix the received first mixer input signal with the local oscillator signal to produce a first mixed output signal from the first non-linear mixer, and provide the first mixed output signal to the driving electrode of the resonator body; and a second non-linear mixer coupled to the sensing electrode of the resonator body, the second non-linear mixer configured to: receive a frequency of the resonator body and the frequency of the local oscillator signal as input frequencies, mix the received frequency of the resonator body with the local oscillator signal to produce a second mixed output signal from the second non-linear mixer, the second mixed output signal being an output signal having a tuned frequency as a function of the frequency of the local oscillator signal and having the same frequency as the first mixer input signal.