基于Wi-Fi信号的地震埋压人员快速求救与搜救系统开发

After severe earthquakes happened, how to save trapped people during the golden 72 hours was the most important thing. However, because of the damage of base stations or block of communication, it is hard for trapped people to contact with the outside world, and they can only seek help by shouting, knocking or other traditional ways, which were labor-consuming and ineffective. For search and rescue, traditional methods like manual searching, sniffer dogs, life detection instruments have disadvantages including limited searching region, easily got disturbed, expensive and so on. In order to address these issues, this paper proposed a fast positioning system based on Wi-Fi signal for locating trapped people. The advantages of this method include a wide scope of coverage, fast speed of transfer, low expenses, and easy to operate. With this method, the efficiency of searching was improved. Different from other mature Wi-Fi positing methods, the proposed RSSI distance measurement algorithm based on Wi-Fi strength, do not have to collect the information of Wi-Fi access points at the beginning, so it is more suitable for the situation after earthquake. With the widely use of mobile phones, the trapped people could use the client application to send distress signal, and the searching and rescuing people could use the RSSI distance measurement model to ascertain the position of the trapped people quickly through the three-point positioning and optimizing process, so helping to allocate the rescue resources more efficiently and improve the rescue effect. Through the field test under different ruin environments of National land search and rescue base, the system shows good operating effectivity, and could meet the need of search and rescue the trapped people.