Performance Modeling and Analysis of LTE/Wi-Fi Coexistence

Abstract

In wireless communications, the fundamental challenge facing mobile operators nowadays is the scarcity of the spectrum and the license fees. Because of the increased traffic, critical performance analysis becomes important to overcome such issues. To tackle these issues and improve the network performance and capacity, a coexistence model of LTE and Wi-Fi with two virtual zones is suggested. The inner zone is the secondary zone, which represents Wi-Fi with an unlicensed spectrum to serve the best effort user data and the outer zone is the primary zone, which represents LTE with licensed spectrum to serve all data connections. The numerical solution of the model is presented using MOSEL-2 simulation and the mathematical solution is derived to validate the model. A threshold minimum bit rate established the user admission. Based on a priority level of the service, most of the traffic is served by the primary LTE zone, however, low priority traffic is moved from the primary LTE zone to the secondary Wi-Fi zone so that the traffic of the entire network is balanced. Although this coexistence sometimes harms LTE performance, the simulation results demonstrate the efficiency of the proposed model in balancing the load over the network, and, consequently, the network performance is improved.