Secure green D2D communication in OFDMA based networks with imperfect channel knowledge

In this paper, we devise a resource allocation scheme for secure communications in a device to device (D2D) communication scenario underlaying an existing orthogonal frequency division multiple access cellular network in which there are some eavesdroppers overhearing the information transmission of cellular network, i.e., from base station (BS) to cellular users. Given the uncertainty of perfect values of channel state information and channel distribution information (CDIs) for the transmitters such as BS and transmitters of D2Ds, the required knowledge about these parameters is feedbacked via some channels of limited capacity. The devised resource management scheme is written in an optimization problem whose solution is subcarrier allocations, transmit power allocations, and determination of the fading space boundaries and CDIs’ boundaries, and are obtained using the particle swarm optimization method. We aim at maximizing the weighted sum of average rate of D2D pairs and average energy efficiency of them while the average secrecy rate of cellular network should be maintained above a predefined threshold. We consider the case where D2D pairs use only their batteries and the case where in addition to the battery, D2D pairs can harvest the energy and use it for the transmission purpose. Using simulations, we evaluate the proposed framework in different situations.