# US 2019/0319599 A1 · Resonator-based sensor and sensing method thereof > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2019/0319599 A1 - Document ID: US20190319599A1 - Status: Published application - Kind: A1 - Application number: 16/137,378 - Filed: 2018-09-20 - Published: 2019-10-17 - Earliest claimed: 2018-04-11 - Assignees: Electronics and Telecommunications Research Institute - Applicants: Electronics and Telecommunications Research Institute - Inventors: Hyunjoong Lee; Yi-Gyeong Kim; Yil Suk Yang; Woo Seok Yang; Chang Han Je - Web page: https://patentgrep.com/patent/US20190319599A1 ## CPC - H03G 3/3036: {in high-frequency amplifiers or in frequency-changers (H03G3/3052, H03G3/32, H03G3/34 take precedence)} - G01N 9/002: {using variation of the resonant frequency of an element vibrating in contact with the material submitted to analysis (G01N9/34 takes precedence)} - G01N 11/16: by measuring damping effect upon oscillatory body - H03G 3/001: {Digital control of analog signals} - H03M 3/488: {using automatic control} - H03M 3/49: {in feedback mode, i.e. by determining the range to be selected from one or more previous digital output values} - H03G: CONTROL OF AMPLIFICATION - G01N: INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES (measuring or testing apparatus or processes other than immunoassay, involving enzymes or microorganisms C12M, C12Q) - H03M: CODING; DECODING; CODE CONVERSION IN GENERAL (using fluidic means F15C4/00; optical analogue/digital converters G02F7/00; coding, decoding or code conversion, specially adapted for particular applications, see the relevant subclasses, e.g. G01D, G01R, G06F, G06T, G09G, G10L, G11B, G11C, H04B, H04L, H04M, H04N; ciphering or deciphering for cryptography or other purposes involving the need for secrecy G09C) ## Abstract A resonator-based sensor and a sensing method thereof for sensing a change in a material that is subject to be sensed which include: generating an oscillation voltage signal by amplifying a current signal output from a resonator in accordance with a physical-chemical change of the material; and generating a gain control signal corresponding to a motional resistance and a clock signal corresponding to a resonant frequency of the resonator are provided. ## Claims ### Claim 1 A resonator-based sensor for sensing a change in a material, comprising: a resonator configured to output a current signal according to a physical-chemical change of the material; an amplifier configured to amplify the current signal to generate an oscillation voltage signal; and a digital automatic gain controller (AGC) configured to generate a clock signal corresponding to a resonance frequency of the resonator and a gain control signal corresponding to a motional resistance of the resonator based on the oscillation voltage signal, wherein the amplifier is controlled by the gain control signal. ### Claim 2 (depends on 1) The resonator of claim 1, wherein the digital AGC comprises a down-mixing envelope tracker configured to generate an m-bit digital signal according to a magnitude of an envelope of the oscillation voltage signal, wherein the m-bit digital signal corresponds to a magnitude of the motional resistance. ### Claim 3 (depends on 2) The resonator of claim 2, wherein the down-mixing envelope tracker comprises: a comparator configured to compare the oscillation voltage signal with a reference threshold to output an up/down signal; a counter configured to generate a counting signal according to the up/down signal; a low pass filter configured to filter the counting signal at a low frequency band; and a down sampler configured to down-sample the low-pass filtered signal to output the m-bit digital signal, wherein a number of bits of the m-bit digital signal is greater than a number of bits of the counting signal. ### Claim 4 (depends on 2) The resonator of claim 2, wherein the digital AGC further comprises a delta-sigma modulator configured to modulate a remaining (m−n)-bit signal generated by subtracting an n-bit coarse signal from the m-bit digital signal in a delta-sigma modulation scheme to generate a 1-bit fine signal, wherein the gain control signal is a sum of the n-bit coarse signal and the 1-bit fine signal. ### Claim 5 (depends on 4) The resonator of claim 4, wherein the digital AGC further comprises a clock generator configured to convert the oscillation voltage signal to a digital voltage signal and generate a plurality of clock signals by adjusting a phase or a frequency of the digital voltage signal, wherein the frequency of the digital voltage signal corresponds to the resonance frequency. ### Claim 6 (depends on 5) The resonator of claim 5, wherein the plurality of clock signals include a first clock signal provided to the down-mixing envelope tracker and a second clock signal provided to the delta-sigma modulator, and wherein the first clock signal has a same frequency as a frequency of the digital voltage signal and the second clock signal has a frequency that is higher than a frequency of the m-bit digital signal. ### Claim 7 (depends on 1) The resonator of claim 1, wherein a magnitude of the oscillation voltage signal is a product of a magnitude of the current signal and a magnitude of a variable resistance determined according to the gain control signal. ### Claim 8 A method for sensing a change in a material, comprising: generating an oscillation voltage signal by amplifying a current signal output from a resonator according to a physical-chemical change of the material; and generating a clock signal corresponding to a resonance frequency of the resonator and a gain control signal corresponding to a motional resistance of the resonator based on the oscillation voltage signal, wherein an amplifier generating the oscillation voltage signal is controlled by the gain control signal. ### Claim 9 (depends on 8) The method of claim 8, wherein the generating a clock signal corresponding to a resonance frequency of the resonator and a gain control signal corresponding to a motional resistance of the resonator based on the oscillation voltage signal comprises generating an m-bit digital signal according to a magnitude of an envelope of the oscillation voltage signal, wherein the m-bit digital signal corresponds to a magnitude of the motional resistance. ### Claim 10 (depends on 9) The method of claim 9, wherein the generating an m-bit digital signal according to a magnitude of an envelope of the oscillation voltage signal comprises: outputting an up/down signal by comparing the oscillation voltage signal with a reference threshold; generating a counting signal according to the up/down signal; filtering the counting signal at a low frequency band; and outputting the m-bit digital signal by performing down-sampling of the low-pass filtered signal, wherein a number of bits of the m-bit digital signal is greater than a number of bits of the counting signal. ### Claim 11 (depends on 9) The method of claim 9, wherein the generating a clock signal corresponding to a resonance frequency of the resonator and a gain control signal corresponding to a motional resistance of the resonator based on the oscillation voltage signal comprises: generating a 1-bit fine signal by modulating a remaining (m−n)-bit signal generated by subtracting an n-bit coarse signal from the m-bit digital signal in a delta-sigma modulation scheme; and generating the gain control signal by summing the n-bit coarse signal and the 1-bit fine signal. ### Claim 12 (depends on 11) The method of claim 11, wherein the generating a clock signal corresponding to a resonance frequency of the resonator and a gain control signal corresponding to a motional resistance of the resonator based on the oscillation voltage signal further comprises converting the oscillation voltage signal to a digital voltage signal and generating a plurality of clock signals by adjusting a phase or a frequency of the digital voltage signal, wherein the frequency of the digital voltage signal corresponds to the resonance frequency. ### Claim 13 (depends on 12) The method of claim 12, wherein the plurality of clock signals include a first clock signal provided to the down-mixing envelope tracker and a second clock signal provided to the delta-sigma modulator, the first clock signal has a same frequency as a frequency of the digital voltage signal, and the second clock signal has a frequency that is higher than a frequency of the m-bit digital signal. ### Claim 14 (depends on 8) The method of claim 8, wherein a magnitude of the oscillation voltage signal is a product of a magnitude of the current signal and a magnitude of a variable resistance determined according to the gain control signal. ### Claim 15 A digital automatic gain controller (AGC) for controlling an oscillation circuit of a resonator-based sensor which senses a change in a material, comprising: a down-mixing envelope tracker configured to generate an m-bit digital signal according to a magnitude of an envelope of an oscillation voltage signal; and a delta-sigma modulator configured to modulate a remaining (m−n)-bit signal generated by subtracting an n-bit coarse signal from the m-bit digital signal in a delta-sigma modulation scheme to generate a 1-bit fine signal, wherein the m-bit digital signal corresponds to a magnitude of a motional resistance of a resonator included in the oscillation circuit, and a gain control signal for controlling the oscillation circuit is a sum of the coarse signal and the fine signal. ### Claim 16 (depends on 15) The digital AGC of claim 15, wherein the down-mixing envelope tracker comprises: a comparator configured to compare the oscillation voltage signal and a reference threshold to output an up/down signal; a counter configured to generate a counting signal according to the up/down signal; a low-pass filter configured to low-pass filter the counting signal; and a down sampler configured to down-sample the low-pass filtered signal to output the m-bit digital signal, wherein a number of bits of the m-bit digital signal is larger than a number of bits of the counting signal. ### Claim 17 (depends on 16) The digital AGC of claim 16, further comprising a clock generator configured to generate a plurality of clock signals by converting the oscillation voltage signal to a digital voltage signal and adjusting a phase or a frequency of the digital voltage signal, wherein the frequency of the digital voltage signal corresponds to the resonant frequency. ### Claim 18 (depends on 17) The digital AGC of claim 17, wherein the plurality of clock signals include a first clock signal provided to the down-mixing envelope tracker and a second clock signal provided to the delta-sigma modulator, wherein the first clock signal has the same frequency as the frequency of the digital voltage signal and the second clock signal has a higher frequency than a frequency of the m-bit digital signal. ### Claim 19 (depends on 15) The digital AGC of claim 15, wherein a magnitude of the oscillation voltage signal is a product of a magnitude of a current signal output from the resonator and a magnitude of a variable resistor of the oscillation circuit determined according to the gain control signal.