Browse > Article
http://dx.doi.org/10.7840/KICS.2011.36A.7.654

Design and Implementation of RF based locating System for NLOS Environment  

Choi, Hoon (부산대학교 컴퓨터공학과 임베디드시스템 연구실)
Baek, Yun-Ju (부산대학교 컴퓨터공학과 임베디드시스템 연구실)
Publication Information
The Journal of Korean Institute of Communications and Information Sciences / v.36, no.7A, 2011 , pp. 654-661 More about this Journal
Abstract
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.
Keywords
RTLS; Real time locating system; NLOS; localization;
Citations & Related Records
연도 인용수 순위
  • Reference
1 Kegen Yu, Guo, Y.J., "NLOS Error Mitigation for Mobile Location Estimation in Wireless Networks," Proc. of Vehicular Technology Conference, pp.1071-1075, Apr. 2007.
2 Larsson, E.G, "Cramer-Rao bound analysis of distributed positioning in sensor networks," Proc. of IEEE Signal Processing Letters, Vol.11, pp.334-337, Mar. 2004.   DOI   ScienceOn
3 Venkatesh S., Buehrer R.M., "A linear programming approach to NLOS error mitigation in sensor networks," Proc. of The Fifth International Conference on Information Processing in Sensor Networks, pp.301-308, Jul. 2006.
4 Riba J., Urruela, A., "A non-line-of-sight mitigation technique based on ML-detection," Proc. of IEEE International Conference on Acoustics, Speech, and Signal Processing, Vol.2, pp.153-156, May 2004.
5 K. W. Cheung, H. C. So, "Accurate approximation algorithm for TOA-based maximum likelihood mobile location using semidefinite programming," Proc. of IEEE International Conference on Acoustics, Speech, and Signal Processing, Vol.2, pp.145-148, May 2004.
6 K. Whitehouse, C. Karlof, and D. Culler, "A practical evaluation of radio signal strength for ranging-based localization," Mobile Computing and Communications Review, Vol.11, 2007.
7 P.-C. Chen, "A non-line-of-sight error mitigation algorithm in location estimation," IEEE Wireless Communications and Networking Conference, June 1999.
8 장현성, 최훈, 정연수, 진영우, 백윤주, "Demo abstract: Distributed RTLS with multidirectional antenna array," IEEE Real-Time and Embedded Technology and Application Symposium, April 2009.
9 손상현, 김잠제, 최훈, 정연수, 백윤주, "Demo abstract: Implementation of RTLS to overcome radio shadow area," IEEE Real-Time and Embedded Technology and Application Symposium, April 2009.
10 부산대학교 과학연구기술동 1층, http://rclit.com/
11 J. J. Caffery Jr., "A new approach to the geometry of TOA location," 52nd Vehicular Technology Conference, 2000. IEEE VTS-Fall VTC 2000.
12 J. O. Smith and J. S. Abel, "Closed-form least-squares source location estimation from range-difference measurements," IEEE Trans. Acoust. Speech Signal Process, Vol.35, No.12, pp. 1661-1669, Dec. 1987.   DOI
13 Texas Instruments, 2.4 GHz IEEE 802.15.4/ZigBee-Ready RF Transceiver (Rev. B), CC2420 Datasheet (Rev. B), 2007.
14 Texas Instruments, Single-Chip Very Low Power RF Transceiver (Rev. A), CC1000 Datasheet, 2007.
15 Nanotron technologies, nanoLOC TRX Transceiver.