Wireless measurement device using surface acoustic wave (SAW)-based micro sensor and method of using the saw-based micro sensor

• US 9,116,034 B2
• Filed: 09/14/2011
• Issued: 08/25/2015
• Est. Priority Date: 09/17/2010
• Status: Active Grant

• Current Assignee: Ajou University Industry Cooperation Foundation
• Original Assignee: Ajou University Industry Cooperation Foundation
• Inventors: LEE, Kee Keun, Kwon, Ick Jin, Oh, Hae Kwan, Yang, Sang Sik, Park, Ik Mo, KIM, Young Kil
• Primary Examiner(s): Kwok, Helen
• Application Number:
  US13/824,005
• Publication Number:
  US 20130174662A1
• Time in Patent Office: 1,441 Days
• Field of Search: 736/49, 735/79, 735/80, 736/02
• US Class Current: 1/1
• CPC Class Codes: G01D 21/00 Measuring or testing not otherwise provided for
• CPC Class Codes: G01H 17/00 Measuring mechanical vibrations or ultrasonic, sonic or infrasonic waves, not provided for in the preceding groups see provisionally also G01H1/00
• CPC Class Codes: G01L 1/165 with acoustic surface waves
• CPC Class Codes: G01L 9/0025 with acoustic surface waves
• CPC Class Codes: G01N 2291/0256 Adsorption, desorption, surface mass change, e.g. on biosensors
• CPC Class Codes: G01N 2291/0423 Surface waves, e.g. Rayleigh waves, Love waves
• CPC Class Codes: G01N 29/022 Fluid sensors based on microsensors, e.g. quartz crystal-microbalance [QCM], surface acoustic wave [SAW] devices, tuning forks, cantilevers, flexural plate wave [FPW] devices microdevices per se B81B
• CPC Class Codes: G01N 29/2481 Wireless probes, e.g. with transponders or radio links
• CPC Class Codes: G06K 19/0675 the resonating marks being of the surface acoustic wave [SAW] kind SAW devices per se H03H9/64
• CPC Class Codes: G06K 19/0717 the sensor being capable of sensing environmental conditions such as temperature history or pressure

Abstract

A wireless measurement device includes a sound acoustic wave (SAW)-based micro sensor converting a wirelessly received pulse signal into an SAW and generating a plurality of pulse signals by reflecting the SAW, and wirelessly transmitting the plurality of pulse signals to measure a variance of an environmental element; and a reader generating and wirelessly transmitting a pulse signal to the SAW-based micro sensor to measure variances in environmental elements.

Claims

1. A wireless measurement device comprising:

a surface acoustic wave (SAW)-based micro sensor converting a wirelessly received pulse signal into an SAW and generating a plurality of pulse signals by reflecting the SAW, and wirelessly transmitting the plurality of pulse signals to measure a variance of an environmental element; and

a reader generating and wirelessly transmitting a pulse signal to the SAW-based micro sensor to measure variances in environmental elements, whenever an interval between the plurality of pulse signals received by reflecting the transmitted pulse signal by the SAW-based micro sensor corresponds to a determined interval between pulse signals of an environmental element,

wherein the reader measures a variance in the environmental element by counting times of pulse signals generated and wirelessly transmitted to the SAW-based micro sensor for a certain amount of time.

2. The wireless measurement device of claim 1, wherein the SAW-based micro sensor comprises:

an antenna wirelessly transmitting and receiving a pulse signal;

an inter-digital transducer (IDT) generating an SAW by applying the pulse signal received at the antenna to a plurality of metallic electrodes formed parallel to one another and converting a plurality of SAWs reflected by a reflector part into a plurality of pulse signals, and wirelessly outputting the plurality of pulse signals via the antenna; and

the reflector part comprising a plurality of reflectors and reflecting the SAW generated by the IDT.

3. The wireless measurement device of claim 2, wherein the IDT has a single phase unidirectional transducer configuration.

4. The wireless measurement device of claim 1, wherein the reader comprises:

an environmental element variance measurement part generating and transmitting a pulse signal for measuring a variance of an environmental element to the SAW-based micro sensor via an radio frequency (RF) part, whenever an interval between the plurality of pulse signals received by reflecting the transmitted pulse signal by the SAW-based micro sensor corresponds to a determined interval between pulse signals of an environmental element,

wherein the environmental element variance measurement part measures a variance in the environmental element by counting times of pulse signals generated for a certain amount of time; and

the RF part wirelessly transmitting the pulse signal generated by the environmental element variance measurement part to the SAW-based micro sensor and transmitting the plurality of pulse signals wirelessly received from the SAW-based micro sensor to the environmental element variance measurement part.

5. The wireless measurement device of claim 4, wherein the RF part comprises:

an antenna wirelessly transmitting and receiving a pulse signal;

a transmitter modulating the pulse signal generated by the environmental element variance measurement part and transmitting the modulated signal to the SAW-based micro sensor via the antenna; and

a receiver modulating the plurality of pulse signals reflected by the SAW-based micro sensor and received via the antenna ANT and transmitting the modulated signals to the environmental element variance measurement part.

6. A method of wirelessly measuring by using an SAW-based micro sensor, the method comprising:

generating a pulse signal and wirelessly transmitting the pulse signal to the SAW-based micro sensor, performed by a reader, to measure a variance of an environmental element;

converting the wirelessly received pulse signal into an SAW, and to measure the variance of the environmental element, generating a plurality of pulse signals by reflecting the SAW, and wirelessly transmitting the plurality of pulse signals, performed by the SAW-based micro sensor; and

generating and wirelessly transmitting a pulse signal to the SAW-based micro sensor and measuring the variance of the environmental element by counting times of pulse signals generated for a certain amount of time whenever an interval between the plurality of pulse signals received by reflecting the transmitted pulse signal by the SAW-based micro sensor corresponds to a determined interval between pulse signals of the environmental element, performed by the reader.