An Improved Method for Indoor Positioning of Wifi Based on Location Fingerprint

Indoor positioning technology is one of the key technologies in the field of wireless sensor network (WSN) research. Received Signal Strength Indication (RSSI) has become the focus of indoor positioning technology research. In order to improve the accuracy of indoor positioning, this paper proposes a WIFI indoor positioning method based on location fingerprint. First, Gauss filtering preprocessing is performed on the RSSI in the fingerprint database to filter out redundant points caused by multipath effects and noise factors, which may cause errors in the construction of the location fingerprint database. Then, according to the working principle of the Bayes algorithm, the posterior probability function of the fingerprint data vector collected by the mobile terminal and the corresponding position of each fingerprint reference point is obtained. Finally, the posterior probability value is used as the weight coefficient on each fingerprint reference point in the target location area, and the location of the mobile terminal is accurately calculated. The experimental results show that the method can effectively improve the indoor positioning accuracy.