Journal of the Korea Convergence Society (한국융합학회논문지)

Korea Convergence Society (한국융합학회)
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Compact Microwave Heartbeat Proximity Sensor Under Human Body Movement

인체 움직임을 고려한 소형 근접 마이크로파 심박 센서

  • Yun, Gi-Ho (Department of Information Communication Engineering, Sungkyul University)
  • 윤기호 (성결대학교 정보통신공학과)
  • Received : 2020.08.26
  • Accepted : 2020.10.20
  • Published : 2020.10.28
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Abstract

In this paper, a small microwave sensor that can be applied to a wearable device is proposed because it can detect the heartbeat signal of a human body moving irregularly at low speed. It consist of balanced microstrip radiation patches in the 2.4 GHz ISM band, self-oscillation detection circuit, and feedback circuit. Based on the theoretical development and simulation, the validity of the proposed structure was confirmed and the manufactured prototype was tested. The board size of the circuit is as small as 65mm × 85㎟, and has a low power consumption of 60mW thanks to the simple RF circuit structure. Finally heartbeat signal has been obtained from a human body moving at low speed (0.5Hz) within a linear distance of 2 to 30mm close to the sensor and a lateral distance of ±20mm.

본 논문에서는 저속으로 불규칙하게 움직이는 인체의 심박신호를 감지하기 할 수 있어 웨어러블 디바이스에 적용 가능한 소형 마이크로파 센서를 제안하였다. 이를 위해 2.4 GHz ISM 대역에서 평형 구조를 갖는 마이크로스트립 방사 패치들과 자체발진 검출회로 및 귀환회로가 구성되었다. 이론 전개와 시뮬레이션을 통해 제안된 구조의 타당성을 확인하였고 제작된 시제품을 측정하였다. 회로의 보드는 65mm × 85㎟의 작은 크기이며, 간단한 고주파 회로구조로 60mW 수준의 작은 전력을 소모한다. 센서와 직선거리 2~30mm, 측면 좌우 거리 ±20mm 범위 내에서 저속(0.5Hz)으로 움직이는 인체로부터 심박신호를 얻을 수 있었다.

Keywords

References

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