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

Abstract

Due to the scarcity of the licensed spectrum, Licensed-Assisted Access Long-Term Evolution (LAA- LTE) network can be deployed 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. By using the genetic algorithm, FDTM tunes 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 existing Wi-Fi networks in unlicensed bands, and (2) fair service differentiation for downlink LAA-LTE traffic. Numerical results show our FDTM scheme can guarantee the throughput of WiFi networks in shared unlicensed spectrum, while supporting proportional fairness for the LAA eNBs with different weights and CW min values.