Due to global climate change as well as economic concern of network operators, energy consumption of the infrastructure of cellular networks, or “Green Cellular Networking,” has become a popular research topic.
Particularly, the two most important reasons to pursue the development of green communications networks are increases in carbon dioxide emissions (CO2) and increases in operational expenditures (OPEX). Hence, energy consumption reduction has to be dealt with in all the main activities, ICT and communications included.
While energy saving can be achieved by adopting renewable energy resources or improving design of certain hardware (e.g., power amplifier) to make it more energy-efficient, the cost of purchasing, replacing, and installing new equipment (including manpower, transportation, disruption to normal operation, as well as associated energy and direct cost) is often prohibitive. By comparison, approaches that work on the operating protocols of the system do not require changes to current network architecture, making them far less costly and easier for testing and implementation.
In this course, we first present facts and figures that highlight the importance of green mobile networking and then review existing green cellular networking research, providing general guidelines and design criteria in order to reduce power consumption, to increase the energy efficiency in cellular networks and to generalize these strategies to ICT systems. A particular focus will be on techniques that incorporate the concept of the “sleep mode” in base stations. It takes advantage of changing traffic patterns on daily or weekly basis and selectively switches some lightly loaded base stations to low energy consumption modes. As base stations are responsible for the large amount of energy consumed in cellular networks, these approaches have the potential to save a significant amount of energy.
