The Design And Realization Of Family Anti-Theft System Based On Sensing Technology

Anti-theft system is an important safety equipment to protect citizens’ personal and property. With the current high rate of technological development, the traditional security measurement for the new tools of crime appears to be insufficient. Therefore, for the weaknesses of existing security devices, it is necessary to design and develop a new anti-theft program, quickly find and stop stealing behavior; these have some significance for the protection of personal property security and maintaining social harmony and stability.The anti-theft system proposed in this paper take a local area of a family or similarly as the basic unit. System functions can be divided into three parts:Front-end monitoring, data processing and transmission parts and monitoring center. The first two sections are involved in this paper; the front end is responsible for monitoring body signals of each sensor node in the part I, part II is responsible for the center processing nodes of communication processing. The sensor nodes are installed at the top of the door or window, once someone entered the active area when system is active, the sensor node detects and sends state to the central processing node immediately. The central processing node is responsible for transmitting the alarm information to the district control center, security personnel will be sent by the monitoring center to prevent potential acts of theft. At the same time, the central processing node will notify the user for subsequent processing via SMS.In the paper, a sensor is used to detect the infrared signals from the human bodies. The sensing data is processed by an ATmegal6MCU firstly, and then sent to the center processing node by a RF circuit with a CC1100chip as a core. The center processing node is designed based on a LM3S8962chip with an ARM as a core, integrated a ME3000GPRS module to sent alarm SMS to the users and an Ethernet interface to connect the neighborhood’s monitor center. An μC/OS-II embedded OS is integrated into the center processing node, which can be used to manage the software and the hardware. A TCP/IP protocol based LWIP is also integrated for Ethernet communication.Active detection mode is applied in the system. Compared with the video monitor mode, it has the advantages of fast response, reducing the burden of monitoring staff and avoid the mistake caused by human eye fatigue. The system needs fewer equipments compared with the infrared monitor method, which can save the cost. Meanwhile, the sensor with the area coverage can be fixed upon the doors or windows almost with no blind area, which enhances the reliability of the system.