A Game-Theoretic Approach for Fair Coexistence Between LTE-U and Wi-Fi Systems

Abstract

LTE over unlicensed band (LTE-U) has emerged as an effective technique to overcome the challenge of spectrum scarcity. Using LTE-U along with advanced techniques such as carrier aggregation, one can boost the performance of existing cellular networks. However, if not properly managed, the use of LTE-U can potentially degrade the performance of co-existing Wi-Fi access points, which operate over the unlicensed frequency bands. Moreover, most of the existing works consider single operator in their proposals. In this paper, an effective coexistence mechanism between LTE-U and Wi-Fi systems is studied. The goal is to enable the cellular network to use LTE-U with CA to meet the quality-ofservice (QoS) needs of its users while protecting Wi-Fi access points (WAPs) for a network with multiple operators. In particular, the problem of LTE-U sum-rate maximization is addressed under user QoS and WAP-LTE-U coexistence constraints. To solve this problem, a cooperative Nash bargaining game (NBG) and a one-sided matching game are proposed. Here, the NBG solves the coexistence issue between LTE-U and Wi-Fi system, while the matching game solves the resources allocation problem in the LTE-U system. These two games repeat until convergence. Simulation results show the quality of the proposed approach over other comparing methods in terms of the per-user achieved rate, percentage of unsatisfied users, and fairness. The result also shows that the proposed approach can better protect the performance of Wi-Fi users, compared to the conventional listen-before-talk scheme.

Wi-Fi/LTE-U Coexistence: Real-Time Issues and Solutions

“…Increasingly, small-cell LTE cellular systems are being planned for deployment in this band. This gives rise to coexistence problems between the cellular (LTE) and Wi-Fi systems which use very different medium access control (MAC) protocols [1], [2]. LTE uses a TDMA/FDMA scheduled approach and Wi-Fi uses a carrier sense multiple access with collision avoidance (CSMA/CA) approach.…”

“…Most existing work on duty cycle based LTE/Wi-Fi coexistence [1], [2], [14], [15] explores issues via analytical and simulation results. While useful, these approaches necessarily ignore several real-time operational challenges that are observed in test-bed deployments.…”

Density Analysis of LTE-LAA Networks Coexisting With WiFi Sharing Multiple Unlicensed Channels

“…The results in [22] indicated that the coverage probability of a user increases with the number of accessible UCs. The fairness between the LTE-U and WiFi networks with multiple UCs was also analysed based on game theory in [23], and the fairness among UEs was analysed in a LTE-U driven multi-UC vehicle-to-everything and fullduplex assisted scenarios in [24] and [25], respectively.…”

Price Competition with LTE-U and WiFi

“…The Wardrop equilibrium conditions suggests the delivered price is 0 in such a condition, which leads to 0 profit for the incumbent SP. Then, from the definition of social welfare, we have lim Proof: In Appendix G, we give the equilibrium price and customer mass served by the incumbent and entrant SPs in (23). In this proof, we can still use those results.…”