A self-adaptive energy efficient transmission mechanism in relay based cellular network

In cellular networks, multiple relay nodes can be deployed in one cell, so there are three transmission modes, direct transmission (DT), two-hop transmission (TT) and cooperative transmission (CT). Combining with the node sleeping method for power saving, different transmission modes will have different energy efficiency for different user equipment (UE). In this paper, a self-adaptive energy efficient transmission (SEET) mechanism is proposed, in which energy efficient relay selection is taken into account to maximize the area energy efficiency (AEE) of each transmission mode. For each UE, it adaptively adjusts the current transmission mode for AEE maximization. The simulation results show that the proposed SEET mechanism has the maximum AEE compared to the mechanisms of only one mode.