Evaluating the Energy Efficiency of UE-to-Network Relay Assisted Device-to-Device Communication

Device-to-Device (D2D)-enabled LTE allows direct communication between users without traversing the cell base station. This paper evaluates the energy efficiency of UE-to-Network relay assisted D2D and the feasibility of using it to reduce energy consumed in data transmission between users. A simulation is developed to simulate a 5G network and calculate the energy consumption of transmitting and receiving data between two users under two scenarios. The first scenario simulates the conventional LTE network, where each device is directly connected to the base station. The second scenario employs D2D where one device acts as a relay to the second. The system is evaluated using different values for the simulation time, packet transmission interval and distance. Attained results show that UE-to-Network Relay Assisted D2D reduces the total energy consumption of devices by up to 40% compared to LTE, with a side effect of slightly increasing the energy consumption of the relay device. Results also show that the energy consumption of network transmission chains under D2D is up to 45% lower compared to LTE.