Coalition Formation Game Based Access Point Selection for LTE-U and Wi-Fi Coexistence

As a promising solution for the next generation mobile networks (5G) deployment, long term evolution-unlicensed (LTE-U) is expected to improve spectrum utilization and channel capacity, which is beneficial for the industrial Internet of Things integrating many heterogeneous networks. However, such technology migration can potentially induce severe interference to the devices and networks originally operating on unlicensed bands, especially to the Wi-Fi network. In this paper, first of all, we emulate the coexistence of LTE-U networks and Wi-Fi networks, and experimentally evaluate their mutual interference relying on deploying time division duplex based OpenWrt wireless routers. Moreover, an LTE-U and Wi-Fi coexistence mechanism is proposed, where users with diverse traffic demands are capable of accessing either the public LTE-U network or its nearby Wi-Fi network. Finally, an access point selection algorithm with the aid of coalition formation game is developed for improving the system's throughput. Sufficient simulations based on Network Simulator 3 demonstrate that the overall throughput of the LTE-U and Wi-Fi hybrid cosystem outperforms that of the single LTE-U network as well as of the single Wi-Fi network.