Projection-Based Location System via Multiple Discriminant Analysis in Wireless Local Area Networks

Dept. of Electr. Eng., Yuan Ze Univ., Taoyuan, Taiwan
IEEE Transactions on Vehicular Technology (Impact Factor: 2.64). 12/2009; DOI: 10.1109/TVT.2009.2025134
Source: IEEE Xplore

ABSTRACT This paper presents a projection-based location system in an indoor wireless local area network (WLAN) environment. Our algorithm projects the received signal strength (RSS) onto a discriminative space such that the information of all access points (APs) is more efficiently utilized. The projection is determined by multiple discriminant analysis (MDA), thereby guaranteeing maximal discriminative information involved in the positioning system. The study conducts a series of experiments on the effects of our approach in a realistic indoor environment. The results show that not only is the positioning accuracy significantly improved, but the system cost, including the computation and data collection, is also greatly reduced at the same time. This is because our approach extracts only useful information for positioning, whereas the redundant noise is discarded to avoid the problem of overfitting and unnecessary calculations. Compared with prior works, this technique can produce a more graceful balance between the positioning accuracy and the computational complexity for the resource-weak clients.

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