A Compact Radio-Frequency Localization System for Rescue Operations

This work presents a radio frequency compact system for rescue operations of missing people to reach in difficult or inaccessible areas not covered by radio or GSM services such as hills, mountains, woods and rural areas. The proposed system based on a high gain antenna, a compact software defined radio (SDR) receiver and a small elaboration unit. The system simulate a GSM base transceiver station and it is able to interrogate a nearby GSM mobile phone, carried on by missing people, and to detect the international mobile subscriber equipment (IMEI). The knowledge of International Mobile Subscriber Identifier (IMSI) and IMEI codes inform the rescue operators of the possible nearby presence of missing persons. The proposed rescue system is sufficiently compact to be mounted onboard of a small unmanned aerial vehicle (UAV) in order to reach inaccessible, dangerous and unknown areas or easily transportable by hand. The obtained preliminary experimental tests show that this detection systems is able to successfully identify the presence of a GSM devices carried on by a victim, by retrieving its (IMSI) which permits to identify mobile users by their SIM card.