Research On The Loss Prevention And Micro Positioning System For Radioactive Source Based On Bluetooth

The radioactive source is more and more widely used in all walks of life, has made an important contribution to promote economic development and social progress. However, when it benefit of mankind, also easy to out of control because of the theft or loss, then triggered a radioactive accident and endangering the safety of environment and masses. Therefore, it has a very important social meaning and application value to strengthen the safety management of radioactive sources. In view of the deficiency of traditional security and loss prevention technology, Bluetooth technology are applied to monitor the radioactive source, then design of the program and debugging it base on hardware and software.Aiming at the limitations and shortcomings of the traditional loss prevention program of radioactive source, this paper put forward a loss prevention and micro positioning system of radioactive source based on Bluetooth. This system is based ARM processor, combined with Bluetooth technology and GSM technology, not only to achieve the function of loss prevention and SMS alarm, but also can ascertain the radioactive source’s position. To achieve the function of radioactive source positioning, this system based on Bluetooth technology and use of RSSI positioning algorithm and three point positioning algorithm. RSSI positioning algorithm first established a model of signal intensity decreases with the increase of the distance, in order to improve the accuracy of the model, pretreatment the measured RSSI value through the Gaussian filter, and using the least square algorithm to fit the curve of signal intensity with distance, then conversion the signal intensity to the distance between nodes. The introduction of the three points positioning method can improve the accuracy of positioning and achieve the positioning accuracy of decimeter. Based on the scheme This system using STMF407 ARM processor as the main control unit, Bluetooth module adopt nRF51822 chip. This system not only uses the traditional sound and light alarm, but also introduced the GSM technology achieved remote SMS alarm. The design of software based on the KEIL development environment, so that the system to achieve a variety of preset functions.This paper tests the functions of the system, the test results show that the system can positioning and monitoring radioactive sources, when radiation source disconnected or beyond the designed area, the system can accurately respond and realize the diversification of alarm. In addition, the use of Bluetooth technology to achieve the loss prevention and micro positioning of radioactive resource, also has few characteristic such as low power consumption, high positioning accuracy, easy to achieve and so on.