Abstract
The need to maximise energy efficiency (EE) for device-to-device (D2D) communication has become an urgent necessity for the fifth-generation wireless networks. In this study, the power allocation problem is considered for the cellular system underlaid with D2D users (DUs) to maximise the EE for the whole network. Firstly, the random distribution of DUs and cellular users (CUs) are described by utilising the homogeneous Poisson point process based on stochastic geometry. Secondly, successful transmission probabilities are deduced. Finally, the optimisation problem for maximising EE is formulated to determine the optimal power values for both D2D and CUs. An adaptive mesh size algorithm is suggested to solve the non-convexity of the EE optimisation problem. Simulation results prove that the suggested technique has the ability to accomplish the near-optimal EE. Furthermore, it has superior performance when compared with the related algorithms.