DOI QR코드

DOI QR Code

Design of the Rain Sensor using a Coaxial Cavity Resonator

동축 공동 공진기를 이용한 물방울 감지 센서 설계에 관한 연구

  • Received : 2018.07.02
  • Accepted : 2018.10.05
  • Published : 2018.10.31

Abstract

In this paper the water sensor using a coaxial cavity resonator is designed and manufactured. The water sensor which can sense water drop linearly has been constructed with voltage controlled oscillator(VCO), coaxial cavity resonator, RF switch, RF detector, A/D converter, DAC and micro controller. The operating frequency range of the designed water sensor is from 2.5GHz to 3.2GHz and the input voltage and current source are 24[V/DC] and 1[A]. The designed sensor circuit includes VCO, RF switch, RF detector which varies the frequency characteristics of the devices in the high frequency of 3GHz. And so we should correct the error of the frequency characteristics of those devices in the sensor circuit. To do this, we make the reference path which switches the signals to the RF detector directly without sending it to the resonator. According to the result of simulation and measurement, we can see that there is 0-50MHz difference between simulated resonator frequency and manufactured resonator frequency.

본 논문은 동축 공동 공진기를 이용한 레인센서를 설계하고 제작한다. 선형적으로 빗방울을 감지할 수 있는 레인센서는 전압 제어 발진기 (VCO), 동축 공동 공진기, RF 스위치, RF 검출기, A / D 컨버터, DAC 및 마이크로 컨트롤러로 구성되었다. 설계된 레인 센서의 작동 주파수 범위는 2.5GHz ~ 3.2GHz이며, 입력 전압과 전류 소스는 24 [V / DC]와 1 [A]이다. 설계된 센서 회로는 VCO, RF 스위치, 고주파수 3GHz에서 소자의 주파수 특성을 변화시키는 RF 검출기를 포함한다. 센서 회로의 주파수 특성에 대한 오차를 교정한다. 이를 위해 공진기에 신호를 보내지 않고 RF 검출기로 신호를 직접 전달하는 기준 경로를 만든다. 시뮬레이션 및 측정 결과에 따르면 시뮬레이션된 공진기 주파수와 제작된 공진기 주파수 사이에 0-50MHz 차이가 있음을 알 수 있다.

Keywords

References

  1. Casaleggio Associati, "The Evolution of Internet of Things", 2011
  2. Bogdan A. Galwas, Jerzy K. Piotrowski, Member, IEEE, and Jerzy Skulski, "Dielectric Measurements Using a Coaxial Resonator Opened to a Waveguide Below Cut-Off" IEEE Trans. Instrumentation and Measurement, vol. 46, no. 2, pp. 511-514, Apr. 1997. https://doi.org/10.1109/19.571898
  3. Shigeru Nakayama, "Development of a microwave moisture sensor for aggregates" Meas. Sci. Technol., vol. 6, no. 7, pp. 429-431, Jul. 1995. https://doi.org/10.1088/0957-0233/6/4/014
  4. G. Muller, "Windshield wiper system with rain detector" United States Patent, 5015931, May 1991.
  5. Y. Netzer "Sealed capacitive rain sensor" United States Patent, US2008/0265913 A1, Oct.30, 2008.
  6. N. Bendicks, "Moisture sensor"United States Patent, 5323637, June 1994.
  7. G. Gajda and S. Stuchly, "An equivalent circuit of open ended coaxial line", IEEE Trans. Instrum. Meas., vol. IM-32, pp. 506-508, Dec. 1983.
  8. Y. M. Lee, J. K. Kim, and J. Hur, "Study on the Empirical Design of Open-ended Coaxial Cavity Resonator", Microwave and Optical Technology Letters, vol. 56, no. 3, pp. 606-610, March 2014. https://doi.org/10.1002/mop.28150
  9. D. K. Cheng, Field and Wave Electromagnetic, Addison Wesley, 1961.
  10. D. M. Pozar, Microwave Engineering, John Wiley and Sons, 3nd Ed., New York: John Wiley & Sons Inc., 1998.
  11. Y. M. Lee, J. K. Kim, and J. Hur, "A Study on the Detection of the Rain Using Open-Ended Coaxial Cavity Resonator", The Journal of Korean Institute of Electromagnetic Engineering and Science, vol. 24, no. 9, pp. 944-950, Sep. 2013. https://doi.org/10.5515/KJKIEES.2013.24.9.944