Journal of the Institute of Electronics Engineers of Korea SP (대한전자공학회논문지SP)

The Institute of Electronics and Information Engineers (대한전자공학회)
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RSSI based Proximity User Detection System using Exponential Moving Average

지수이동평균을 이용한 RSSI 기반 근거리 사용자 탐지 시스템

  • Yun, Gi-Hun (Department of Electronics Engineering, Dongguk University) ;
  • Kim, Keon-Wook (Department of Electronics Engineering, Dongguk University) ;
  • Choi, Jae-Hun (Electronics and Telecommunications Research Institute) ;
  • Park, Soo-Jun (Electronics and Telecommunications Research Institute)
  • Received : 2009.11.10
  • Accepted : 2010.06.09
  • Published : 2010.07.25
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Abstract

This paper proposes the recursive algorithm for passive proximity detection system based on signal strength. The system is designed to be used in the smart medicine chest in order to provide location-based service for the senior personnel. Due to the system profile, single receiver and uni-direction communication are applied over the signal attenuation model for the determination of user existence within certain proximity. The performance of conventional methods is subjective to the sight between the transmitter and receiver unless the direction of target is known. To appreciate the temporal and spatial locality of human subjects, the authors present exponential moving average (EMA) to compensate the unexpected position error from the direction and/or environment. By using optimal parameter, the experiments with EMA algorithm demonstrates 32.26% (maximum 40.80%) reduction in average of the error probability with 50% of consecutive sight in time.

본 논문에서는 실버케어시스템인 스마트 약상자의 사용자 위치파악을 목적으로 Received Signal Strength Indication (RSSI) 기반 근거리 사용자 탐지 시스템을 제안한다. 상기 시스템은 RSSI값을 사용하여 근거리 내 사용자 유무를 파악하는 단일노드 기반 측위기술을 사용하였다. 단일노드 기반 측위기술의 문제점인 Non Line of Sight (NLoS) 통신환경 내 오차 보정을 목적으로, 시스템에 지수이동평균을 적용하여 RSSI값의 급격한 변화에 강인한 시스템을 구현하였다. 고령자의 행동패턴을 고려한 피실험자 대상 실험을 통하여, NLoS 통신황경 내 RSSI값이 급격히 변화할 경우 지수이동평균을 적용함으로써 오차발생확률이 평균 32.26%, 최대 40.80% 감소함을 확인하였다.

Keywords

Acknowledgement

Grant : 차세대 IT 기반 사업화 기반조성

Supported by : 정보통신연구진흥원

References

  1. "2005∼2030 시도별 장래인구추계," 통계청, 2007
  2. I. Getting, "The global Positioning System," IEEE Spectrum, Vol. 30, no. 12, pp. 36-47, December 1993. https://doi.org/10.1109/6.272176
  3. N. B. Priyantha, A. Chakraborty and H. Balakrishnan, "The Cricket Location-Support System," Proceedings of the 6th annual international conference on Mobile computing and networking, pp. 32-43, Boston, Massachusetts, United States, August 2000.
  4. P. Bahl and V. N. Padmanabhan, "RADAR: an in-building RF-based user location and tracking system," Proceedings of IEEE INFOCOM 2000, pp. 775-784, Tel Aviv, Israel, March 2000.
  5. R. Want, A. Hopper, V. Falcao and J. Gibbons, "The Active Badge Location System," ACM Transactions on Information Systems, Vol. 10, no. 1, pp. 91-102, January 1992. https://doi.org/10.1145/128756.128759
  6. B. Brumitt, B. Meyers, J. Krumm, A. Kern and S. Shafer, "EasyLiving: Technologies for intelligent environments," Proceedings of the 2nd International Symposium on Handheld and Ubiquitous Computing, Bristol, UK, pp. 12-29, September 2000.
  7. Li Cong, Weihua Zhuang, "Nonline-of-sight error mitigation in mobile location," IEEE Transactions on Wireless Communications, Vol. 4, no. 2, pp. 560-573, March 2005. https://doi.org/10.1109/TWC.2004.843040
  8. Texas Instruments' CC2430 datasheet.
  9. Robert G. Brown, "Smoothing, Forecasting and Prediction of Discrete Time Series," Prentice Hall, pp. 97-122, 1963.
  10. Richard W. Bohannon, "Comfortable and maximum walking speed of adults aged 20–79 years: Reference values and determinants," Age and Ageing, Vol. 26, no. 1, pp.15-19, January 1997. https://doi.org/10.1093/ageing/26.1.15
  11. Autonics Corporation's ENC-1-1-T-5 datasheet.
  12. National Instruments Corporation web site, http://www.ni.com/
  13. Edward T. Hall, "The Hidden Dimension," Anchor Books, pp. 113-129, 1966.