Energy Consumption Evaluation For LTE Scheduling Algorithms Takoua Ghariani ∗ ,Badii Jouaber ∗ ∗ Institut Mines-Telecom/Telecom SudParis CNRS UMR 5157 SAMOVAR Takoua.Ghariani@it-sudparis.eu , Badii.Jouaber@it-sudparis.eu Abstract—Reducing energy consumption over mobile networks and devices is an important and challenging issue. On the one hand, power is a limited resource on mobile devices and its usage should be optimized. On the other hand, energy consumption constitutes an important item within operating expenditure (OPEX) for network providers. In the literature, many studies are dedicated to evaluate scheduling mechanisms from the energy consumption perspec- tive. However, most of these only consider few well known schemes such as Proportional Fair, Best-CQI and Round Robin. In the paper, we extend these studies to include new promising scheduling techniques such as PF, EXP-PF and MLWDF algo- rithm. In addition, we consider multiple metrics related to QoS, energy and fairness. Performance results show that MLWDF is more energy efficient than EXP-PF and PF schemes while providing better QoS for users. Index Terms—LTE, Network, Wireless, Energy, Green, Power, scheduling, PF, EXP-PF, MLWDF I. I NTRODUCTION Reducing energy consumption is considered as one of the main challenges within cellular networks. Energy directly impacts the QoE (Quality of Experience) of users since it determines the battery lifetime and therefore service availabil- ity. For network providers, energy consumption represents the most important expense among other operating costs. The way data is scheduled over the air interface directly impacts energy consumption. Scheduling algorithms are part of the radio resource management (RRM) mechanisms. They are among the key elements that define the behaviour and the performances of cellular networks and directly impact resource allocation and QoS (Quality of Service) issues. Scheduling algorithms have been widely studied for re- source management and in particular for dynamic resources allocation on shared channels. Scheduling optimization is gen- erally based on multiple criteria including QoS requirements, fairness, mobility, efficiency, radio conditions and available resources, but not on power consumption. Recently, energy issues are more and more considered in the ICT (Information and Communication Technologies) sector and in particular for wireless networks. This concern different networking components, data centers, protocols and mechanisms. Regarding scheduling, although some studies already exist in the literature, there is still a need for in deep studies and proposals in order to achieve better energy efficiency while maintaining high QoS and network efficiency levels. In this paper we evaluate some promising scheduling algo- rithms over LTE networks. Performance evaluations are conducted under different cell load conditions and schedulers are evaluated in terms of energy efficiency, average throughput, packet loss rate and fairness. The rest of this paper is structured as follows: next sec- tion presents LTE resource management background and the related work regarding scheduling and energy efficiency. In section III we present our performance and energy efficiency evaluations of new scheduling algorithms, with discussions and comparisons. Section V concludes the paper and intro- duces future work. II. BACKGROUND AND RELATED WORK A. LTE resource management LTE PHY uses Orthogonal Frequency Division Multiple Access(OFDMA) on the downlink (DL) [2]. The available bandwidth is divided into physical resource blocks (PRBs) which represent the smallest granularity the resource allocation manager can assign to each user. A PRB consists of 12 consecutive subcarriers for one slot (0.5 ms) ( Fig 1). Fig. 1: Resource Grid B. LTE scheduling algorithms In the literature, several studies were dedicated to the eval- uation of the performances of different scheduling algorithms over LTE networks. The main considered evaluation metrics include cell capac- ity, user throughput and fairness among users. 978-1-4673-7468-2/15/$31.00 c 2015 IEEE