Two level cooperation for energy efficiency in multi-RAN cellular network environment

In this paper, by exploiting the availability of multiple cellular radio access networks (RANs), we propose a novel two-level cooperative access network framework for superior energy efficiency. Geographically co-located RANs mutually cooperate each other through the combined use of base transceiver station (BTS) level intranetwork cooperation and RAN level internetwork cooperation. By jointly applying the two types of cooperation, BTSs within individual RAN as well as BTSs of several RANs communicate and intelligently cooperate for dynamically minimizing the number of active BTSs and thus reduce energy utilization at the access network level. Extensive simulations are carried out for exploring the degree of energy savings and sleeping patterns of BTSs of each cooperating RANs as well as that of the combined network. Simulation results show that through the proposed joint cooperation, each cooperating RAN gains substantial economical benefits by significantly reducing its energy expenditure. Furthermore, comparison with the cases of intranetwork and internetwork cooperation acting alone reveals that by participating in the joint cooperation, each RAN can achieve much higher energy savings.