Design And Implementation Of Indoor Positioning System Base On Location Fingerprint

The study of indoor positioning technology has thirty years. People using ultrasound, infrared, radio frequency identification technology developed a variety of indoor positioning systems for getting different positioning accuracy in different environments. However, they usually require more expensive hardware equipment, has complex installation process, are not suitable for large-scale promotion. In recent years, with the802.11standard continuous improvement and development, the wireless network has been widely used by business and personal users, covering almost every corner in life. Meanwhile, the mobile intelligent terminal equipment has been widely popular. The situation provides new opportunities and challenges for the study of indoor positioning system.With easy deployment and low cost advantages of wireless LAN-based indoor positioning system, is a hot technology research for indoor positioning in recent years. In this paper, the existing research results as a reference, the main work and contributions are as follows:(1) Built a wireless peer-to-peer network based on OpenWrt system. Traditional wireless network architecture has limitations, resulting in limited communication, is not conducive to large-scale expansion, and requires the support of wired network. Using OpenWrt system to build a wireless peer-to-peer network can solve the inconvenience of traditional wireless networks and provide important protection for indoor positioning system design and distributed data storage.(2) Designed and implemented indoor positioning systems based on location fingerprinting. In wireless peer-to-peer networks, we introduce the collection and processing of fingerprint information of the location, choose weighted K-nearest neighbor(WKNN) method to calculate the location result. Based on this, the indoor positioning system is developed. The system will accomplish most work of calculating positioning result and storing location data on the locate server, terminal equipment is only responsible for the results of fingerprint information acquisition and positioning display. It reduces system maintenance costs. Experiments verify the correctness of the system.(3) Proposed a scenario of multi-location server deployment in peer-to-peer network. For large indoor environments, it needs to deploy multiple locate servers simultaneously for working regularly when installing indoor positioning system. With study and simulation of server deployment, an evaluation model for multi-server deployment is given and an algorithm is designed. Experiments demonstrate the effectiveness of the program.(4) Proposed a strategy of data distributed storage for indoor positioning system. The data for indoor positioning system is mainly divided into two categories:the position fingerprint data and indoor map data. This paper used two different data storage strategy. For the location fingerprint data, it is stored on the nearest location server and is completely different on each server. For the indoor map data, it is entered only on the local server, and is synchronized automatically by the server. When synchronization work is completed, all of servers have the same indoor map data, which is suitable for update operation of the map data. Experiments verify the effectiveness of the synchronization strategy.