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Real-Time Respiration and Heartbeat Detector Using a Compact 1.6 GHz Single-Channel Doppler Sensor

소형화된 1.6 GHz 단일 채널 도플러 센서를 이용한 실시간 호흡 및 심장 박동 감지기

  • Lee, Hyun-Woo (Division of Electrical and Computer Engineering, Chungnam National University) ;
  • Park, Il-Ho (Division of Electrical and Computer Engineering, Chungnam National University) ;
  • Kim, Dong-Wook (Division of Electrical and Computer Engineering, Chungnam National University)
  • 이현우 (충남대학교 전기정보통신공학부) ;
  • 박일호 (충남대학교 전기정보통신공학부) ;
  • 김동욱 (충남대학교 전기정보통신공학부)
  • Published : 2007.04.30

Abstract

This paper presents a real-time respiration and heartbeat detector comprised of a 1.6 GHz single-channel Doppler sensor and analog/digital signal processing block for remote vital sign detection. The RF front end of the Doppler sensor consists of an oscillator, mixer, low noise amplifier, branch-line hybrid and patch antenna. We apply artificial transmission lines(ATLs) to the branch-line hybrid, which leads to a size reduction of 40 % in the hybrid, while its performance is very comparable to that of a conventional hybrid. The analog signal conditioning block is implemented using second order Sallen-Key active filters and the digital signal processing block is realized with a LabVIEW program on a computer. The respiration and heartbeat detection is demonstrated at a distance of 50 cm using the developed system.

본 논문에서는 사람의 생체 신호를 감지하기 위해 1.6 GHz 단일 채널 도플러 센서와 아날로그 및 디지털 신호 처리부로 구성되어 있는 실시간 호흡 및 심장 박동 감지기를 개발하였다. 도플러 센서의 RF Front End는 발진기, 믹서, 저잡음 증폭기, 브랜치-라인 하이브리드, 그리고 패치 안테나로 구성되어 있다. 센서에 사용된 브랜치-라인 하이브리드는 기존의 하이브리드에 비해 40 % 정도 크기를 줄이면서도 상당히 유사한 성능을 가지도록 인공 전송 선로(artificial transmission line)를 사용하였다. 아날로그 신호처리부는 2차 Sallen-Key 능동 필터를 사용하여 제작되었고 디지털 신호 처리부는 LabVIEW를 사용하여 컴퓨터상에서 구현되었다. 개발된 시스템은 최대 50 cm 거리에서 사람의 호흡과 심장 박동을 측정함으로써 성능을 검증하였다.

Keywords

References

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