Fundamental Limits of Energy Efficiency in Wireless Networks

Publication Type:

Thesis

Source:

CentraleSupélec, Université Paris-Saclay, Volume PhD, Volume PhD, p.88 (2016)

Abstract:

The task of meeting an ever growing demand for better quality of user experience in wireless communications is challenged by the amount of energy consumed by the technologies involved and the methods employed. Not surprisingly, the problem of reducing energy consumption needs to be addressed at various layers of the network architecture as well as from various perspectives. This thesis addresses some important energy saving possibilities at the physical layer of wireless network architecture in order to find energy efficient solutions. In the first part of this thesis, we explore the idea of energy efficiency at a fundamental level. Starting with answering questions such as 'What is the physical form of information?', we build a simple communication device in order to isolate the key steps in the physical process of communication and we study how each of these steps finally in uences the energy efficiency of the communication system. In the second part, we use tools from stochastic geometry to theoretically model a cellular network so as to analyze its energy consumption. Exploiting the tractability of such a mathematical modeling, we explore the conditions under which the energy consumption can be either reduced or utilized more efficiently or both.

Further, we introduce the concept of caching users' data at the edge of the network (namely the final Base Station (BS) that is in contact with the end user) and show quantitatively how incorporating caching in the network can help improve the energy efficiency. We also extend this treatment to a Heterogeneous Network (HetNet) scenario (namely when there are more than one type of BSs deployed) and study various key performance metrics. We also explore the conditions where energy efficiency of such a system can be improved. The results in thesis provide some key ideas regarding improving energy efficiency in a wireless cellular network thereby contributing to the advancement towards the next generation (5G) cellular networks.