This paper presents an RFID outdoor localization system that is able to localize hundreds of active transponders in the area of one square kilometer using three RFID receiving stations. The RFID outdoor locator is designed for the tracking of casualties during mass disasters. Active transponders are included in triage tags that are fastened to all casualties during the first wave of rescue operations. Direction of arrival of each transponder and GPS position of three receiving stations determine the position of each active transponder in the area. The location of the transponder is displayed on a mobile terminal in maps. The paper describes a design and simulations of such system. The precision of localization of realized prototypes of the system is measured. The results and applications using the proposed RFID outdoor locator are discussed.
