Secure and opportunistic communication with interference cancellation against powerful and full-duplex attackers.

In this paper, we consider the problem of multiple active and full-duplex (FD) attackers in physical-layer security of wireless communications. The attackers can eavesdrop the legitimate signal from a transmitter to a receiver and jam it at the same time with a high power. The channel realizations, pilot signals, and jamming signals of the attackers are not known at the legitimate nodes. This gives a difficulty because there are not enough degrees of freedom in the received signal space. However, we propose a novel scheme to opportunistically remove the jamming signals out of the received signals to reliably decode the legitimate signal. The numerical results show that there is a significant improvement in the secrecy rate (SR) compared to the conventional scheme. Especially, the higher the transmit power of the attackers, the better the performance of the proposed scheme. [ABSTRACT FROM AUTHOR]