Fair Downlink Traffic Management for Hybrid LAA-LTE/Wi-Fi Networks

Abstract

Due to the scarcity of the licensed spectrum allocated for mobile communication systems, licensed-assisted access long-term evolution (LAA-LTE) network is recently proposed to deploy in unlicensed spectrum, which is currently occupied by different Wi-Fi systems. It is a very challenging problem to ensure fair coexistence between LAA-LTE and Wi-Fi networks, in terms of spectrum sharing and traffic management. To solve this problem, a fair downlink traffic management (FDTM) scheme is proposed in this paper for hybrid LAA-LTE/Wi-Fi networks. FDTM aims to tune the minimum contention window ( $CW_{min}$ ) values and assigns feasible weights for the LAA eNBs with different traffic loads, thus to achieve; 1) fair spectrum sharing with the coexisting Wi-Fi networks in unlicensed spectrum and 2) fair service differentiation for downlink LAA-LTE traffic. Numerical results show our FDTM scheme can guarantee the throughput performance of Wi-Fi networks in shared unlicensed spectrum while supporting proportional fairness for the LAA eNBs with different traffic loads.