DOI QR코드

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비가시성을 고려한 RF 기반 측위 시스템의 설계 및 구현

Design and Implementation of RF based locating System for NLOS Environment

  • 최훈 (부산대학교 컴퓨터공학과 임베디드시스템 연구실) ;
  • 백윤주 (부산대학교 컴퓨터공학과 임베디드시스템 연구실)
  • 투고 : 2010.12.27
  • 심사 : 2011.06.08
  • 발행 : 2011.07.30

초록

RTLS(Real Time Locating System)은 사람이나 사물의 위치를 실시간으로 추적하는 시스템이다. 이 시스템에서는 RTLS 리더가 태그와 무선 통신으로 시간이나 거리 등을 측정하고, 위치 엔진은 이를 이용하여 태그의 위치를 추정한다. 하지만 사물을 위치를 추정하는 데 있어 비가시성에 따른 측정 오류는 성능에 심각한 영향용 미친다. 비자시성은 측위 시스템을 실제 환경에 적용하기 위해 반드시 일어나는 요소이며, 이를 해결하기 위해 본 논문에서는 거리를 역추적하여 알맞은 리더를 찾아내는 선택법을 이용한 새로운 측위 시스템을 제안한다. 제안한 기법을 실제 구현하여 실험한 결과 기존 기법에 비해 50% 이상 향상된 것을 알 수 있었다.

RTLS (Real-time locating systems) are used for tracking the location of people or assets in real time. In this system, RTLS readers continuously communicate with RTLS tags for measuring time or ranges and location engine tries to calculate accurate location of tags. However, when we attempt to apply this system to real world, the non-line-of-sight(NLOS) problem can be critical to the system performance because of the obstacles. In this paper, we suggest a new location estimation method for an NLOS environment using a reader-selection strategy. We have implemented all components of the locating system and carried out experiments in a test-bed. The accuracy of the system is 50% better than that of the existing general locating system.

키워드

참고문헌

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