WiFi position fingerprint positioning method based on weighted chi-square distances

Abstract

The invention discloses a WiFi position fingerprint positioning method based on weighted chi-square distances. According to the method, a reliable and stable fingerprint database is established, and positioning accuracy and effectiveness of positioning can be effectively improved. The method comprises the following steps of: S1: in an offline measurement stage, establishing the fingerprint database; S2: in an online positioning stage, according to a signal strength vector of each wireless access point AP, which is acquired by to-be-positioned points, calculating weighted chi-square distances of signal strength vectors of the to-be-positioned points and a fingerprint vector in the fingerprint database; S3: carrying out sorting from big to small on the weighted chi-square distances obtained by calculation, and selecting K reference points (K represents the number); and S4: according to position coordinates of the reference points, estimating position coordinates of the to-be-positioned points. The method adopts a variance filtering method in the offline measurement stage, so that noise values in signal strength values received at the reference points can be effectively removed, and accuracy of fingerprints in the fingerprint database is improved.

Description

technical field [0001] The invention relates to a WiFi position fingerprint positioning method based on a weighted chi-square distance, and belongs to the technical field of position positioning. Background technique [0002] With the rapid development of the mobile Internet and the widespread use of smart devices and mobile communications, the demand for location-based services is also increasing, and people's requirements for timely, accurate, and fast location information are also getting higher and higher. Today, outdoor positioning technology has developed relatively mature. GPS has been widely used in outdoor environments, can provide users with more accurate location services, and is widely used in people's production and life (such as Baidu maps and shared bicycles). GPS technology mainly relies on the propagation of signals in the air and buildings, but due to multi-path propagation and multi-site propagation phenomena such as refraction and diffraction of propagat...

AI Technical Summary

Problems solved by technology

[0010] However, the defects of the prior art include: for example, patent number 201610695797.0, patent name: a WiFi fingerprint indoor positioning method, but the patent must delineate the positioning area, and need to establish the location fingerprint library LFDB of the L sampling points, and The location fingerprint library LFDB performs k-means clustering, and the Euclidean distance must be used as the evaluation criterion for similarity

In this way, the unreliability and instability of fingerprints in the fingerprint library

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