Enhanced Power Saving Scheme for Next Generation Wireless Networks

With the explosion of mobile devices, such as smart phones, tablets as well as many types of wearable devices, there demand for higher battery lifetime. This is also needed due to power consuming applications running on these mobile devices, such as video streaming and online gaming. Consequently, energy conservation is extremely important in wireless networks. The Discontinuous Reception (DRX) mechanism is widely adopted in Long Term Evolution (LTE) networks to conserve battery in mobile devices. However, the sleep period of DRX mechanism not only introduces high handover latency but also reduces the downlink scheduler efficiency.;In this work, we propose a new method, which is called Longer Awake Time, to minimize the handover latency without increasing the power consumption. In the proposed method, we adjust the On Duration Timer appropriately and through simulation demonstrate that the handover latency can be decreased to the same level as when the DRX is dis- abled. This is achieved without decreasing the UEs battery lifetime. The impact of DRX mechanism on downlink scheduling by using Maximum Largest Weighted Delay First (M- LWDF) algorithm is also studied comprehensively. We proposed a novel utility based scheduling scheme (USS), to reduce packet loss which was caused by DRX sleep mode. This is achieved 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 is achieved when compared with traditional scheduling algorithms, such as Proportional Fairness (PF) and M-LWDF. We present a mathematical analysis to investigate the impact of the DRX parameters on the downlink scheduler during intra-LTE handover. Based on the analysis, we propose an enhanced DRX-Aware scheduling (eDAS) mechanism that can balance the trade-off between application QoS requirements and UEs power consumption. The eDAS scheduler accounts for both static and mobile UEs and the parameters are guided by the mathematical analysis. Simulation analysis show that the proposed eDAS scheme achieves higher power saving rate and lower packet loss rate when compared with traditional scheduling algorithms such as PF and M-LWDF.