Design Of Indoor WiFi Positioning System Based On Android Platform And Its Implementation

Science and technology is developing everyday, and information is the inexhaustible motive force for the development of science and technology. The needs of picking up, saving and exchanging information connect the world as a huge network which promotes social development. Furthermore, the location information is getting more and more attention.The demand of location information divides into two categories, the outdoor positioning and the indoor positioning. The outdoor positioning such as GPS satellite positioning system and Beidou satellite positioning system is widely used in our daily life. However, due to cost, accuracy, complexity and other factors, the indoor positioning has no perfect solution yet, which needs to be further studied on.The indoor positioning technology includes RFID, UWB, WiFi, Bluetooth and so on. Due to various factors, they have not been widely used now. However, the demand of indoor positioning is increasing everyday. The research on indoor positioning is urgent.WiFi is a technology which connects the wireless network adapter and Access Point for communicating. WiFi positioning technology is based on wireless network which is connected by wireless network adapter and Access Point. Nowadays, the coverage of WiFi hotspot is the most important part of the construction of smart city. The WiFi can be seen in major tourist attractions, railway stations, airports, shopping malls and so on. If we can use these devices effectively, it’ll promote the popularity of indoor WiFi technology by reducing the cost of system.Traditional WiFi positioning system always uses the Cient/Server architecture. This architecture needs the server equipments, which increasing the cost of devices and developing. Morever, the client device needs to connect the server by network, which reduces the real-time and accuracy of positioning. In the choice of positioning algorithm, the algorithm bases on RSSI(Received Signal Strength Indication) has obvious advantages than others. However, it has no error compensation, so we need to purpose some micro improvement.In order to realize more accurate with less cost, this thesis designs a light, convenient and off-line WiFi indoor positioning system. The system based on Android platform is developed, which is based on the improved RSSI algorithm added by after verification method to avoid the excessive migration of the position coordinates. Compared with the conventional WiFi positioning system, the database of the system is integrated in the equipment to avoid the positioning delay and failure caused by the connection of the database and the communication inconvenience. After testing, the system can work stably and control the range of error within 3 meters in the corridor room scene, which can meet the requirement of indoor mobile positioning.