Successive Artificial Noise Cancellation for Security Enhancing Spatial Modulation

Spatial modulation (SM) as a new transmission technique has a wide application prospect in multiple-input multiple-output (MIMO) wireless communications. In this paper, a novel physical layer security enhancing scheme using artificial noise (AN)is proposed for SM systems. In the proposed scheme, the transmitted signals contain the useful information symbols and the AN that is designed by exploiting the knowledge of the channel state information (CSI) over the legitimate channel. A new detection scheme is also proposed, which detects the information symbols by using signals received across two successive time slots such that the AN can only be perfectly cancelled at the legitimate receiver while confusing the passive eavesdropper. Furthermore, the simulation results on secrecy rate verify that the proposed security enhancing scheme can achieve a satisfactory performance.