Full-Duplex Relay-Aided D2D Communication in Heterogeneous Network with Imperfect CSI

The allowance of direct communication between devices bypassing the base station (BS) is eased through device-to-device (D2D) communication. To overcome the limitation of users separation, cooperative relaying helps to offer wider network coverage and reduce the amount of power consumption. In this paper, the coverage probability and the signal-to-interference-plus-noise ratio (SINR) are analysed in a full duplex relay aided D2D underlaying cellular network model. Concurrently, power optimization problem is offered to enhance the sum rate and SINR of the cellular link while meeting the power constraints of the relay nodes and satisfying the minimum requirements for D2D users in presence of imperfect channel state information (CSI). A comparison between AF and DF is also provided. It is noteworthy that an imperfect CSI is assumed, to present a more realistic environment. Numerical results are provided to show that the lack of a perfect channel can degrade the system performance and coverage. In addition, the power optimization algorithm helps to improve the coverage probability and enhance the system rate in presence of imperfect CSI.