Power control for energy efficient D2D communication in heterogeneous networks with eavesdropper

In general heterogeneous networks, the interference from other communication systems is a main factor for degrading the performance in terms of data rate, so that each system is required to minimize the interference to other systems. However, if the eavesdropper is additionally considered in the heterogeneous networks, the signal from other systems can be utilized for disturbing the information recovery of the eavesdropper. Based on this idea and the importance of the energy efficient communication in Internet of Things (IoT) system, we propose a power control scheme for improving the energy efficiency of device-to-device communication while assisting the secure communication of wireless local area network by interfering with the eavesdropper. We derive a closed-form expression for an optimal power control factor as a function of system parameters. The simulation results confirm the accuracy of analysis and show that the proposed scheme outperforms the conventional scheme in terms of the energy efficiency.