Energy efficiency is of vital importance for telecommunications equipment in future networks, especially battery-constrained mobile devices. In the long term evolution-Advanced (LTE-Advanced) network, the carrier aggregation (CA) technique is employed to allow user equipment (UE) to use multiple carriers for high data rate communications. However, multi-carrier transmission entails increased power consumption at user devices in uplink networks. In this paper, we propose a new dynamic carrier aggregation (DCA) scheduling scheme to improve the energy efficiency of uplink communications. Two scheduling methods, i.e., serving the longest queue (SLQ) and round-robin with priority (RRP), are designed to reduce transmit power while maximizing the utilization of wireless resources. The proposed scheme is analyzed in terms of both the data rate and energy conservation. We build an ideally balanced system (IBS) to investigate the performance upper bound of the DCA scheme, and derive closed-form expressions. Simulation results demonstrate that the proposed scheme can not only enhance the energy efficiency but also perform closely to the optimal IBS.
['Fei Liu', 'Kan Zheng', 'Wei Xiang', 'Hui Zhao']
Design and Performance Analysis of An Energy-Efficient Uplink Carrier Aggregation Scheme