Indoor positioning is a very important topic, mainly in terms of continuity of services [1]. This leads to many theoretical and experimental works in this field using a large range of techniques, from purely GNSS approaches to physical sensors networks. Among all these techniques, Wireless Local Area telecommunication Networks (WLANs) or Wireless Personal Area telecommunication Networks (WPANs) present the potential advantage of a widespread deployment for local telecommunication purposes: in this case, there will be apparently no need for a specific localisation infrastructure. In this paper, we will present our latest works on such a wireless network, based on Bluetooth modules (USB adapter connected to independent computers). Some papers have already dealt with this case ([2], [3], [4]) but our approach is slightly different: we propose to present a method using local measurements and calculating the location at the terminal end. The modelling is based on a progressive experimental method that can briefly be described as follows: within a building, we deploy the Bluetooth modules and evaluate various parameters (received signal strength, link quality, etc.) for each independent module, and successively for a combination of two to five transmitters; we create data-bases that are used to determine an equivalent to "propagation models" in 2D within the building; we then use these data bases to experimentally validate the resulting localisation accuracy that can be achieved in a 2D environment. The building used for this work is such that many realistic configurations are possible, from large areas (of more than 140 square meters) to corridors or offices. Furthermore, there are also many wall structures (glass walls, light and heavy walls, etc.). The results show the localisation accuracy versus various system parameters (number of Bluetooth modules, location of these modules, measurements used for the location calculation, etc.) and also versus actual locations within the building.
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