Towards 5G

10Energy-efficient Wireless OFDMA Networks

Cong Xiong and Geoffrey Ye Li

Georgia Institute of Technology, Atlanta, GA USA

10.1 Overview

Information and communication technology is playing an important role in global greenhouse gas emissions. It is reported that the total energy consumed by the infrastructure of cellular wireless networks, wired communication networks, and the Internet takes up more than 3% of the world electric energy consumption nowadays and the portion is expected to increase rapidly in the future. As an important part of information and communication technology, wireless communications are responsible for greenhouse gas emissions and resultant environmental issues. Meanwhile, widespread application of wireless services requires ubiquitous access and has triggered rapidly booming energy consumption in wireless networks. Such an escalation of energy consumption also causes high operational expenditure from electricity bills for operators and unsatisfactory user experience due to the limited battery capacity of wireless devices, besides a large amount of greenhouse gas emissions. Energy-efficient wireless networks, which emphasize energy efficiency (EE) as well as spectral efficiency (SE), have been proposed as an effective solution and are becoming the mainstream for future wireless network design. Unfortunately, EE and SE do not always coincide and may conflict, even in new-generation wireless networks such those based on orthogonal frequency division multiple ...