Performance analysis of various co-existence methods with Wi-Fi in unlicensed bands

Recently, it is highly issued to extend wireless communication service on licensed band to unlicensed band as a part of effective utilization of the limited spectrum resources. Because Wi-Fi service is widely used in the targeted unlicensed band, the co-existence performances of Wi-Fi with the wireless communication service should be investigated. In this paper, several co-existing methods such as LBE and FBE methods based on listen-before-talk (LBT) and duty cycle (DC) methods are investigated. For the fair sharing spectrum, the number of collisions and latency are derived in situations when various co-existence methods are applying with Wi-Fi. The scenarios are evaluated using Monte-Carlo simulations. According to the simulation results, LBE and FBE have the least effects on collisions and latency of Wi-Fi, respectively. Further more, when Wi-Fi and LBE is co-existed, it shows the best performance for the total devices.