Design of Anti-Lost Early Warning System Based on Bluetooth

The missing elderly and children have occurred from time to time in recent years. Thus, an anti-loss system has been designed and developed to effectively prevent the occurrence. The system consists of a single-chip microcomputer terminal and a handheld device terminal in which the single-chip microcomputer terminal is provided with STC89C52RC as the central controller, and the handheld device is provided with an Android smartphone. With a Bluetooth module, the Bluetooth communication connection is established between the single-chip microcomputer and the smartphone APP, the specific APP with Bluetooth alarm is developed on the smartphone. The sound and light alarm circuit is designed on the single-chip microcomputer terminal. When the distance between the single-chip microcomputer terminal and the smartphone exceeds 5 m, the Bluetooth communication between both of them is disconnected, and the single-chip microcomputer terminal alarm module and the smartphone APP start to enter the alarm working state simultaneously.