The Discuss On A Anti-Lost System Based On Bluetooth4.0

With the development of the society and technology, it has become faster and faster for people to follow steps of the world and it has also become increasingly urgent for them to go out for meeting, negotiation, travel, shopping and so on. Because of this, cases of losing belongings among these people are extremely common. Even the lost incidents of children and the old may also occur frequently at the same time. So the research on the Anti-lost System has a great value in the market.Bluetooth4.0standard was released in2010. Since then, the BLE (Bluetooth Low Energy), part of Bluetooth4.0, has been playing a significant role in people’s life. This new born Bluetooth standard provides a longer covered distance, more advanced ability of anti-interference and the most important lower energy consumption. At this point, it only needs a button cell to survive a ten-year life.Based on the needs in the real life, this article has worked on the BLE protocol especially focusing on the level structure of the protocol stack and the states, roles, modes designed for the BLE devices. After that, the realization of this protocol on Android system will be brought in and be discussed, and the development of the BLE related applications is going to be covered. Then the traditional Anti-lost System should be dealt with, meanwhile, a lower cost and less complicated Anti-lost System will be designed and realized based on those former ones.The system mainly consists of two parts, a master end and a slave end. The slave end is a BLE module which should be able to work on the broadcast state. Users should equip the belongings with it. The master end is an application based on the Android smart device. Users can monitor their belongings only by installing this application into their Android smart phones which should support the BLE protocol. When working, the slave end should work on the broadcast state and send broadcast message on specified channels while the master end should keep scanning to obtain the power level of the signals sent by the slave. By analyzing the levels obtained, the master should make a decision on whether the slave is safe or not. If not, ring the alarm to alert the user.An experiment will be performed to test the performance of the System designed in this article. Reaction Time will be used to measure the ablity for the System to prevent belongings losing. It is concluded that the System can quickly take actions to ring the alarm when the distance between the master and the slave has reached a specified value.