Accurate signal strength prediction based positioning for indoor WLAN systems

With development of IEEE802.11 based wireless local area networks (WLAN) there are several techniques to provide an accurate estimation of the location of mobile devices in indoor environment were presented. As the only available information at receiver side is the received signal strength indication (RSSI) from each WLAN access points (AP), technique called RSSI fingerprinting was proposed [1]. However one of the main drawbacks of RSSI based location is the extensive calibration phase to build a signal fingerprint.