Multi-Hop Relay Network for Base Station Energy Saving and Its Performance Evaluation

The base station (BS) turning off scheme has been considered as a feasible solution to save energy of wireless networks. At the same time, it is also important to maintain quality of service (QoS) of the cell whose BS is turned off. In this paper, we consider multi-hop relay (MR) and cooperative transmission (CT) in cellular network and evaluate performances focusing on the tradeoff between QoS (i.e., user throughput and outage probability) and energy consumption when a BS is turned off. The result shows that combining cellular network with MR (MR network) is more robust in maintaining QoS level when a BS is turned off. Moreover, the MR network can also reduce overall energy consumption depending on the energy consumption level of a relay station (RS). Finally, a cooperative multi-hop relay (CMR) network which supports both intra-sector and inter-sector cooperative relaying is proposed to fill up the coverage holes.