Energy Optimization of D2D Communications Using Relay Devices and Data Entropy

International audienceDevice-to-device (D2D) communications are an-nounced as a cornerstone of the next generation of wirelesscommunications (5G). They offer the promise to drasticallyreduce the energy consumption of devices (phones, tablets,etc.), and increase network coverage areas. In this paper, wepropose to study the influence of a relay device in a D2Dcommunication. We aim to show the impact of relaying on theenergy consumption. Our work provides a new perspective onthe D2D communications by integrating innovative topology inthese communications. Indeed, D2D is a local-area-based typeof communications. Then, we assume that the data transmittedby different users have a certain correlation between each other.Therefore, a new approach is to use the common entropy betweeneach D2D devices to reduce the amount of data relayed by therelay device. This minimization leads inevitably to a reduction ofthe energy consumed by the relay device, and the network. Weanalyze the optimal case (in terms of position of the relay nodeand correlation coefficient between different data) to validate theproposed topology, based on conditional entropy