Abstract: WLAN fingerprint location technology has become a hot topic in the field of indoor location, but the traditional location algorithm are particularly susceptible to spatial environment changes which will reduce the accuracy. To solve this problem, this paper proposes the indoor location algorithm based on two-stage position correction. This paper analyzes the influence of the conductivity of indoor air on the RSSI. On the basis of the traditional algorithms’ locating results as initial location position, this algorithm uses K-Nearest Neighbor algorithm (KNN) to construct all users’ initial location position and fingerprint mapping. On this foundation, off-line and on-line stages position correction between users by multidimensional scaling (MDS) is calculated. At the last, the initial location position is optimized with two-stage position correction and the end localization result of the target is obtained. The experimental results show that the algorithm can deal with the dynamic changes of the environment effectively and correct the location results. The average error of the traditional algorithm is reduced by more than 10% after optimization of this algorithm.

Key words: indoor location, environment changes, two-stage position correction, multidimensional scaling, optimization of locating results