Indoor Navigation Based On Openwrt Wi-Fi Mesh Network

With the development of science and technology, the large-scale construction is more and more, indoor navigation is becoming increasingly important. Although the GPS (Global Positioning System) positioning and navigation can be achieved outdoors, however it cannot be achieved indoors, since satellite signals cannot penetrate buildings.In this paper, we research indoor navigation based on OpenWrt Wi-Fi mesh (OWM) network, shopping malls, for example, using shop adjacency relation database as simple indoor map. First manually configure OWM network, and then change the configuration progress into program for building a network quickly. Second, create the distributed database of shop adjacency relation based on OWM network, sync databases on the whole network. Third, implement indoor navigation system based OWM network, which is a navigation software running on the Android platform. Users enter current location and destination in the software, then it queries indoor map data, output the optimal route via the shortest path algorithm. Users also can add shop and adjacency relation information via the software.First of all, indoor navigation of the thesis is based OWM network configured manually or by program, not the existing mall Wi-Fi hotspots, increasing the controllability of the network, while the navigation system can also make better use of the characteristics of the network. The OWM network nodes are composed of OpenWrt system routers, as OpenWrt system is programmable, the entire network can be in accordance with the demand for custom functionality.Second, shop adjacency relation database is a simple indoor map in the system, store administrators add shop adjacency relation via navigation software, and then sync databases among all network nodes, which effectively solves the lack of indoor map. This method to get indoor map is simpler and less costly.Finally, the shop adjacency relation database is distributed database based on OWM network, as indoor map, effectively avoids the shortcomings of the centralized database organizationally, and improves reliability of the system. Mesh network is self-organizing, multi-hop, but a long time to access data. Indoor navigation based on OWM network combines the advantages of the mesh network and distributed database, and it is self-organizing, multi-hop, a short time to access data at the same time, reducing the data transfer consideration. Indoor navigation based the OWM network combines the advantages of OpenWrt, Mesh network and distributed database. In the future, we can do some research in using clustering algorithm to reduce the number of vertices, shorten navigation time, and using network bridge to connect nodes for full network communication.