Full-duplexing jamming attack for active eavesdropping

Abstract

In this paper, we introduce smart jamming attack by an active eavesdropper (or jammer) who is capable of full-duplex communications. Using self-interference cancellation, the active eavesdropper can have no degraded signals from jamming, while the powers of jamming signals can be decided to manipulate a legitimate transmitter's transmission powers in decreasing the secrecy rate when the legitimate transmitter is unaware of the jammer's capability of full-duplex communications. We derive a closed-form expression for an upper-bound on the secrecy rate and use it to allocate the jamming powers. From this, we can show that the secrecy rate can be zero under full-duplex attack for any total transmission power of the legitimate transmitter. This result demonstrates that a transmitter should be aware of the possibility of active eavesdropping with jamming attack.