Design And Development Of A Location System Based On Wi-Fi

In recent years, wireless lan technology has been gaining popularity around the world with its sub standard 802.11b/g receiving major deployments in many indoor environments. Various location types ranging from the small business offices to the large multi-floored corporate buildings are having wlan equipments to provide wireless local area network and Internet access. This project is about an indoor and outdoor location system that works in conjunction with these 802.11 standard access points preinstalled in the locations. It combined the two location methods which result from this project's study and development.This system has three subsystem including mobile client, server and the wifi access point and it is capable of identifying the position of the device in relation to the indoor/outdoor environment, using logical address and MAC address or received signal strength. Firstly, a radio map will be pre-constructed by some data process programms and mathematical algorithm. Then, the location information database will be constructed. In this project, the location system integrates all of the three subsystem including the AP, the mobile device and the server system together and work well. In the developing of the wireless access point subsystem, it considerd not only the individual privacy but also the security for the transfering data through the tunnel. The development of the mobile client based on the Android platform and the Google map api. The server subsystem's main program is result of the customization from an opensource progrect. It is designed and developed with high performance and good reliability according to the model of multiprocess and I/O multiplexing.In the process of studying position algorithm and the system design and development, I read a lot of paper and make the best use of the software engineering knowledge which lead the project achieved sucessfully.