Research And Implementation Of RSSI Based WLAN Indoor Positioning

With the rapid growth of of mobile Internet applications,wireless location technology has been more and more demanding in indoor application.location-based services are becoming increasingly urgent.Due to the wide application prospect of WLAN based location service,WLAN indoor positioning has become a hot spot of research in recent years because of its high positioning accuracy,low cost of deployment,wide applicability and application.The company's existing WLAN positioning system uses three point positioning algorithm for positioning,in practical applications,the positioning accuracy is not high and the delay is longer,it is difficult to meet the needs of large-scale shopping malls real-time positioning.Therefore,based on a full understanding of the existing indoor positioning system,considering the actual needs and the advantages and disadvantages of the existing indoor positioning system.An indoor positioning system with relatively high positioning precision and short time delay is proposed and implemented.The major work of the thesis is as follows:1.Based on the study of the original indoor positioning system,the WLAN channel scanning mode is optimized to reduce the positioning time delay and to improve the real-time performance of the system.The interference factors that affect indoor positioning are analyzed to optimize the treatment of the RSSI value2.By considering indoor obstacles and signal attenuation to establish proper propagation model and correct the propagation model through sampling,then establish a relatively accurate off-line fingerprint database.3.The RSSI difference algorithm is proposed to improve the positioning algorithm and the positioning coordinate is corrected.4.Non WIFI interference sources such as Bluetooth,microwave oven,wireless cameras,cordless phones are located through spectrum analysis,making it more convenient for enterprise to optimize network,and remove fault.The accuracy of indoor positioning is further improved.5.By improving the positioning algorithm,we designed and optimized a RSSI based WLAN indoor positioning system using modular software engineering idea.We conducted experiments to contrast both the positioning accuracy and the system performance of the original and improved scheme,and verified the effectiveness of the improved scheme.To sum up,RSSI based WLAN indoor positioning optimization system,not only has improved the terminal positioning accuracy and shortened the positioning time delay,but also implements the positioning of non WIFI interference sources.Through the corresponding interface,it can be effectively used in shopping malls,car parks,hospitals,museums,etc.to provide such services as navigation and positioning,traffic analysis,real-time monitoring,accurate delivery and other.