Abstract
WLAN location determination systems are gaining increasing attention due to the value they add to wireless networks. This paper focuses on how to determine the mobile devices’ location indoor by using signal strength (SS) in 802.11-based system. We propose an 802.11-based location determinat-ion technique Nearest Neighbor in Signal Space (NNSS) which locates mobile objects via collecting the sensed power strengths. Based on NNSS, we present a modification Modified Nearest Neighbor in Signal Space (MNNSS) to enhance the location determination accuracy by taking into account signal strength of more reference points in each estimating location of the mobile objects. In NNSS, we compare the measured SS (signal strength) with the SS of each reference point recorded in database to find the best match, but in MNNSS, we not only compare the measured SS with that of each reference point, but also the reference points around it, so it increases the location determination preciseness. The experimental results show that the location information provided by MNNSS assures higher correctness than NNSS. Implementation of this technique in the WLAN location determination system shows that the average system accuracy is increased by more than 0.5 meters. This significant enhancement in the accuracy of WLAN location determination systems helps increase the set of context-aware applications implemented on top of these systems.
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© 2006 Springer-Verlag Berlin Heidelberg
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Wang, CD., Gao, M., Wang, XF. (2006). An 802.11-Based Location Determination Approach for Context-Aware System. In: Huang, DS., Li, K., Irwin, G.W. (eds) Intelligent Computing in Signal Processing and Pattern Recognition. Lecture Notes in Control and Information Sciences, vol 345. Springer, Berlin, Heidelberg . https://doi.org/10.1007/978-3-540-37258-5_1
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DOI: https://doi.org/10.1007/978-3-540-37258-5_1
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