A wireless sensor system includes an array of wireless nodes, each wireless node including a wireless transceiver transmitting over the radio frequency (RF) and a processor. The array of wireless nodes is distributed over an area. In operation, the array of wireless node determines the presence of an...http://www.google.com.au/patents/US20040090329?utm_source=gb-gplus-sharePatent US20040090329 - RF based positioning and intrusion detection using a wireless sensor network
