Journal of the Korea Academia-Industrial cooperation Society (한국산학기술학회논문지)

The Korea Academia-Industrial cooperation Society (한국산학기술학회)
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Design of Radiation Pattern Reconfigurable Antenna for Vital Signal Sensing Device Attached on Wristband and SAR Analysis on Human body

팔목 부착형 생체신호 측정기기에 사용가능한 방사패턴 재구성 안테나 설계 및 인체 SAR 영향 분석

  • Lee, Chang Min (Graduate School of NID Fusion Technology, Seoul National University of Science and Technology) ;
  • Jung, Chang Won (Graduate School of NID Fusion Technology, Seoul National University of Science and Technology)
  • 이창민 (서울과학기술대학교 NID융합기술대학원) ;
  • 정창원 (서울과학기술대학교 NID융합기술대학원)
  • Received : 2014.10.20
  • Accepted : 2015.01.08
  • Published : 2015.01.31
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Abstract

This paper presents radiation pattern reconfigurable antenna for Fitbit Flex wristband which detects vital signal. Also, the paper presents Specific Absorption Rate (SAR) from the loop-dipole radiation pattern reconfigurable antenna based on the position of human body. The proposed loop-dipole radiation pattern reconfigurable antenna produces two opposite side direction radiation pattern using two RF switches. The resonant frequency of the radiation pattern reconfigurable antenna is Bluetooth communication bandwidth (2.4 - 2.485 GHz) and the maximum gain of the proposed antenna is 1.96 dBi. The proposed antenna satisfied the standard SAR value of 1.6 W/kg in 1 g tissue of the human body when the Bluetooth communication input average power of 0.04 W is excited to five parts of human body (head, chest, stomach, back, wrist). The maximum SAR value of in this simulation is presented in the part of head.

본 논문은 생체신호를 측정하는 팔목부착용 Fitbit Flex상에 구현된 방사패턴 재구성 안테나에 관련된 논문이다. 또한 본 논문에서 제안하는 루프-다이폴 방사패턴 재구성 안테나의 인체 내 부위별 전자파 흡수율 (Specific Absorption Rate; SAR)에 관한 논문이다. 본 논문의 루프-다이폴 방사패턴 재구성 안테나는 두 개의 RF 스위치를 사용하여 서로 반대방향의 두 가지 방사패턴을 구현한다. 방사패턴 재구성 안테나는 블루투스 (Bluetooth) 통신 대역 (2.4 - 2.485 GHz)을 사용하며, 최대이득은 1.96 dBi이다. SAR 시뮬레이션 결과로 블루투스 입력 평균전력 0.04 W가 팔목을 포함하는 인체 내 다섯 개 부위 (두부, 가슴, 배, 등, 팔목)에 입력되었을 때 Federal Communication Commission (FCC)의 기준인 단위 1 g 당 1.6 W/kg을 모두 만족함을 확인하였다. 또한 최대 SAR 값은 두부에서 1.12 W/kg이다.

Keywords

References

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