Securing SSK-based Communications via Friendly Jamming and Antenna Selection

Due to the inherent broadcast nature of wireless communications, privacy and security are crucial concerns in modern communication systems. In order to ensure the reliability and security of wireless communications, this paper proposes a novel friendly jamming joint antenna selection (AS) scheme to protect the secrecy of the space shift keying (SSK) based communication system where a source node (S), a destination node (D) and an eavesdropping node (E) are considered. In the proposed scheme, the jamming signal resides in the null space of the legal link (from S to D) and is transmitted by S along with the valid information, which causes no interference to D. However, for the eavesdropping node, it is difficult for E to obtain the relevant information of the legal link because of the spatial decorrelation. Therefore, the jamming signal has the ability to protect the transmitted valid information by causing interference to E. Moreover, the generalized Euclidean distance antenna selection (GEDAS) scheme is proposed to further improve the physical layer security (PLS) of the system by maximizing the difference of the average mutual information (AMI) between D and E. The simulation results show that the proposed joint scheme outperforms the traditional random selection scheme in terms of secrecy rate (SR), secrecy capacity (SC) and bit error rate (BER).