Accuracy limits of in-room localisation using RSSI

Indoor localisation using inexpensive, non-dedicated wireless devices has spun great attention in the last years. We witness the ubiquitous presence of Wi-Fi access points in offices and homes, soon followed by the increasing spread of low-power, low-cost wireless nodes using the Bluetooth and, in perspective, ZigBee technologies. The presence of a potentially high number of wireless transmitters in indoor spaces has pushed researchers to investigate whether their built-in received signal strength indicator (RSSI) could be exploited to gain information on the relative position of a receiver with respect to a number of transmitters and, by knowing in advance the position of those transmitters, to pinpoint the receiver's position.