Energy Efficiency of Radio Units and its Impact on RAN Energy Consumption

Abstract: As mobile telecommunications networks continue to grow, energy consumption continues to grow with it. This will without a doubt affect both the operational expense for network operators and the environment due to air pollution from power stations. As of today, a lot of radio units are consuming more power than necessarily, and with the growing industry this will have a substantial impact in the future. One way to address this issue is to make radio units more energy efficient. To approach this a study on Radio 2217, an Ericsson remote radio unit, was conducted. The study involved work on both hardware and software level. In order to test and evaluate the results a real LTE radio base station was set up. An LTE network was also modeled in Matlab with the purpose to show how different power save features of radio units could reduce the energy consumption. The findings of this work shows that the existing power save implementations of the radio unit could definitely be improved. The power save features Cell-Sleep and MIMO-Sleep were improved by 36 % and 3.4 % respectively. It also showed that the energy consumption in a mobile network could be reduced by up to 57 % by modernizing hardware and adding power save features.