Trade-off Analysis of QoS-Aware Configurable LTE Downlink Schedulers

The voice, video, and data traffic can be carried as IP packets over Long Term Evolution (LTE) networks which bring the cellular communication to the fourth generation (4G) era. LTE enables this digital convergence by offering higher capacity, including inherent IP support in its architecture, and supporting multi-user diversity scheduling. However, recent increases in Voice over IP (VoIP) and video traffic usage require the prioritization of the real-time traffic to meet its stringent QoS requirements. In this paper, the existing Round Robin and Best CQI schedulers are enhanced to enable the QoS support to the real-time traffic. For both schedulers, a configurable parameter, which determines the degree of priority level, is introduced so that the real-time traffic throughput can be administratively controlled without jeopardizing the overall network performance. Simulation results demonstrate the trade-off among the real-time traffic throughput, the overall system throughput and the overall system fairness for various scenarios.