Secure robust resource allocation using full-duplex receivers

Abstract

This paper studies a robust resource allocation framework to enhance physical layer security where it is assumed that the system is equipped with a full-duplex (FD) receiver in contrast to conventional frameworks where a half-duplex (HD) receiver is at hand. Conventionally, relays are used as jammer to reduce the signal quality received by the eavesdroppers so as to increase the secrecy transmission rate between the legitimate transmitter and receiver. This is referred to as cooperative jamming (CJ). In a system equipped with a FD receiver, we propose to use the FD receiver as the jammer, i.e., the FD receiver simultaneously transmits jamming signals toward the eavesdropper while receiving data from the transmitter. The proposed scheme eliminates the need for external helpers, i.e., jamming relays which is welcome from practical point of view. We consider different scenarios to compare the proposed scheme against the CJ scheme in which, under a legitimate transmitter power constraint, optimal power allocation is obtained for each scenario to maximize the secrecy rate. To take into account the impact of imperfect state information of the channels between the eavesdropper and other nodes on the network, worst-case optimization approaches are considered. Simulation results demonstrate that for certain positions of the jamming relay and eavesdropper, the proposed system can outperform the conventional CJ schemes.