Method Research Of WLAN Indoor Localization Based On Double Fingerprint Overlying

In recent years, with the development of wireless network technology, indoor location area is received the focus of attention by people. WLAN indoor localization method based on double fingerprint overlying has been widely used because of its high accuracy and without adding extra hardware and simple and easy and so on. We deeply study fingerprint location method in the wireless access point selection and positioning algorithm.Based on analyzing the existing indoor positioning method on AP selection, this paper presents a AP clustering method based on Fisher criterion. This method can not only make full use of the signal intensity of the mean and variance to measure the resolution of fingerprint reference point, but also to the position correlation consistent AP together as a class, through the election of members of a class to represent the characteristics of the center. The experimental data confirm that the AP selection method improve the positioning accuracy while reducing the use of redundant AP, to achieve the purpose of "downsizing".Aiming at the disadvantage of traditional single fingerprint location method is susceptible to environmental noise, This paper proposes using two sets of fingerprint positioning, which uses two sets of fingerprint positioning method of superposition. The method uses a grid location theory, which can reduce the location estimation range, and eliminate singularity noise point, and effectively reduce interference of noise environment.Finally, through verification and analysis of measured data, this paper proves the double fingerprint overlying compared to the traditional single set of fingerprint positioning can significantly improve the positioning accuracy, provides an important reference for the realization of precise indoor positioning.