Date Added: Sep 2010
WLAN Positioning has been presented by many approaches in literature's using the characteristics of Received Signal Strength (RSS), Time Of Arrival (TOA) or Time Difference of Arrival (TDOA), Angle Of Arrival (AOA) and cell ID. Among these, RSS approaches is the simplest method to implement because there is no need of modification on both access points and client devices whereas its accuracy is terrible due to physical environments. For TOA or TDOA approach, the accuracy is quite acceptable, but most research have to modify either software or hardware on existing WLAN infrastructure. The scales of modifications are made on only access card up to the changes in protocol of WLAN. Hence, it is an unattractive approach to use TOA or TDOA for positioning system.