Energy-Efficiency Based Resource Allocation for D2D Communication and Cellular Networks

In this paper, we present an energy efficiency based resource allocation scheme for a heterogeneous integrated network consisting of device-to-device (D2D) communication system and a cellular communication system. We study the power allocation and network mode selection scheme for users' coexistence of both systems in terms of energy efficiency maximization of the heterogeneous network (Het Net). The formulated optimization problem is a fractional non-convex problem, the standard convex optimization techniques cannot be applied directly. With the use of fractional programming and dual problem formulation, we are able to solve the non-convex problem, taking into consideration the minimum data rate required, the minimum received power and the maximum device dependent radiated power constraints. Results show that the optimal solution can be achieved with a relatively small number of iterations. Also results show that the increase in both the number of users and system data rate does not necessarily lead to an increase in the energy efficiency of the network.