The Research Of Indoor Positioning Technology Based On WLAN

With the rapid increase of data services and multimedia services,people’s need of positioning and navigation is increasing day by day,especially in the complex indoor environment such as the airport hall,storage,super market,library, undergroung parking and so on, we often need to ensure the indoor positions of the stations or the stations’ owner, devices and items, While as to the outdoor positioning technology, we are familiar with the GPS positioning technology invented by United States,the GLONASS global satellite navigation system invented by Russia and the BeiDou satellite navigation system invented by China.These outdoor positioning technologies are mature, and now we can use these technologies in our daily life,and these positioning technologies have provided real-time, all-weather and global navigation service in the field of land,sea and air for us.In the open environment,the outdoor positioning technology can provide a high-precision positioning,while in the complex indoor environment,the precision of the outdoor positioning will not meet our requirements,so the indoor positioning technology emerges at the right moment. Now there are many kinds of indoor positioning methods on the market,such as the method based on infrared,the method based on ultrasonic, the method based on bluetooth,the method based on ultra wide band,the method based on WLAN and the method based on ZigBee.In this paper, what the author studies on is mainly about the signal strength of WLAN indoor positioning system.In a wireless local area network,we need not add any hardware and we can locate a wireless station.In this paper, we regard the indoor positioning system based on WLAN as the research object,and we use the method of combining theoretical analysis and practice, the station will collect the RSSI from the AP and send the RSSI to the database to establish fingerprint;and then when we locate the station,we will compare the RSSI sequences collected from the testing site with the RSSI sequences in the database to determine the location of the station.In the paper, the work finished by author as following:First,the author has collected the material related indoor positioning technology, and fully studied the indoor positioning technology in the domestic and foreign development present situation,and analyzed the advantages and disadvantages of indoor positioning technology of the current market.It is concluded that the non-parameter indoor positioning technology will be the important development direction in research of indoor positioning field.Second,the author has designed and implemented a fingerprint of indoor positioning system based on RSSI according to the characteristics of WLAN,and then the author has test the whole system. At last,the author summarized the whole positioning system and analyzed the defects which exist in the system and put forward the direction of the future work.