Efficient Downlink Scheduling with Discontinuous Reception (DRX) Mechanism in LTE Network

Long Term Evolution (LTE) is being widely deployed to support real-time applications, such as voice over IP and video games. These power consuming applications create new challenges for resource allocation. Therefore, providing efficient resource allocation as well as extending user equipment's (UE) battery lifetime are two important goals in LTE network. Maximum Largest Weighted Delay First (M-LWDF) algorithm is one of the primary downlink scheduling mechanisms currently used for real-time applications. The Discontinuous Reception (DRX) mechanism, which is widely adopted in LTE to conserve the mobile phone's battery resources, results in higher latency and higher packet loss rate due to its sleep mode. The impact of DRX mechanism on downlink scheduling by using M-LWDF algorithm was studied comprehensively for the first time. Then a novel scheme, utility based scheduling scheme (USS), was proposed to reduce packet loss which was caused by DRX sleep mode by considering the remaining DRX awake time at UE and adjusting the DRX parameters. The simulation results show that by using this proposed scheme, significant performance gain will be achieved when compared with traditional scheduling algorithms, such as Proportional Fairness (PF) and M-LWDF. Packet delay and packet drop rate will be decreased by 23.5% and 59.5% respectively.