On the Energy Efficiency Limit of Dense Heterogeneous Cellular Networks

Abstract

This paper studies the energy efficiency of a dense heterogeneous cellular network (HetNet) consisting of.. independent Poisson point processes (PPPs) of base stations (BSs) and what the maximum limit on the energy efficiency can be achieved by cell association. The cell load statistics is first derived for power-law cell association functions and it can characterize the accurate void cell probability of a BS in each tier of the HetNet. A green cell association (GCA) scheme is proposed based on the downlink spectrum efficiency per unit power consumption of a BS and its GCA function is derived in a very simple and feasible form. The energy efficiency of a BS is defined as the mean downlink spectrum efficiency per unit power consumption and its tight lower bounds and limits for the GCA, maximum received power association (MRPA) and nearest base station association (NBA) schemes are all found. We show that the energy efficiency achieved by the GCA scheme is the maximum energy efficiency limit that is not surmounted by other non-green cell association schemes such as MRPA and NBA and the cell loads between different tiers are also balanced by the GCA scheme very well.