Enhanced LBT Algorithm for LTE-LAA in Unlicensed Band

In this paper, we focus on the deployment of LTE technologies coexisting with Wi-Fi technologies in the unlicensed spectrum 5 GHz. Listen before talk (LBT) functionality is required in unlicensed band in order to ensure the fair coexistence among different operators. In this work we focus on enhancing current LBT algorithm with contention window size adaptation for LTE-LAA so as to achieve QoS fairness besides the channel access fairness. Simulation results show that LTE-LAA with LBT mechanism does not impact Wi-Fi services more than an additional Wi-Fi network. In addition, our proposed enhanced LBT algorithm could achieve more than 11% and 7% performance gain in UPT and transmission latency, respectively. Furthermore, the simulation result also shows the advantage of proposed LBT algorithm over original LBT procedure in the case of two LTE operators coexistence.