Indoor positioning system and method based on WLAN (wireless local area network)

Abstract

The invention discloses an indoor positioning system and method based on the WLAN (wireless local area network) in order to determine the signal transmission intensity of a terminal and eliminate the signal transmission intensity difference caused by the terminal type and the like. According to the system, wireless APs (access points) which are controlled by a data center and have wireless signal data collection functions are arranged, each sampling point is covered with ranges of at least three AP collection signals, and the APs are dispersed in different rooms to increase the positioning accuracy. Indoor space is divided into a plurality of small blocks by taking half of a square meter as a unit, and the APs collect the terminal signal intensity at the center of each small block, and a fingerprint database is established. According to the system and the method, the physical accessibility and the internal relevancy of data in the database are combined, the range of matched candidate points is effectively reduced, and the computation complexity is reduced; a WKNN (weighted K nearest neighbor) method is adopted to predict the final position of a client during real-time matching; according to the terminal movement condition, a movement compensation mechanism is further proposed so as to improve the positioning accuracy. Algorithm improvement is performed by the aid of passive positioning, and the system and the method have the characteristics of wide applicability, high positioning accuracy, low computation complexity and stable operation.

Description

technical field [0001] The invention relates to the technical field of wireless communication, in particular to an indoor positioning system based on a wireless local area network. Background technique [0002] The rapid development of wireless communication systems makes people's demand for positioning more and more high. With the rapid development of wireless technologies such as IEEE802.11, WLAN technology is rapidly popularized all over the world due to its wide coverage, fast transmission speed, and low network construction cost. Wireless APs are spread all over hospitals, libraries, museums, and schools. , airport halls and other large public buildings in cities. Therefore, WLAN-based wireless indoor positioning has also become a research hotspot in indoor positioning today. [0003] At present, the fingerprint algorithm has a better positioning effect in WLAN positioning, but the fingerprint algorithm inevitably requires a signal transmitter and a signal receiver. ...

AI Technical Summary

Problems solved by technology

The RSSI value collected by just adjusting the direction of the antenna may differ by 10dbm, which is unbearable in positioning

In addition, the fingerprint algorithm has the problem of excessive computational complexity in the matching stage. Traditional methods cannot fully consider the characteristics of the entire system environment to reduce the computational complexity of matching.

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