Improving energy efficiency for terminals in wireless networks with relay nodes

In this paper we study the potential gain of energy efficiency of user equipment by splitting downlink and uplink in a wireless cellular network with relay nodes, taking the conventional Reference Signal Received Power (RSRP) based scheme as baseline. The relay network is structured by placing an omni-directional relay node in the centre of each sector. The downlink and uplink between one user equipment and one base station may choose different transmission schemes with or without forwarding via relay nodes. The performance of the downlink and uplink splitting scheme is evaluated in terms of energy efficiency defined as the ratio of capacity and power consumption. The numerical simulation results indicate that energy efficiency of some user equipment can be improved by splitting downlink and uplink, an average gain about 16% over the conventional RSRP based selection scheme is observed.