Covert Information Embedded Spatial Modulation

In this letter, we propose a new convert information embedded spatial modulation (SM) system for secure communications, in which the transmitter tries to send covert information to the specific receiver while keeping the unintended receiver unaware of the transmission. In the proposed system, the covert information bits are conveyed via the activated antenna index while the common information bits are via the modulation symbols. Specifically, the convert information modulation is achieved by carefully designing the space-time mapping principle so that it is disguised as a conventional SM antenna index. Furthermore, an efficient detection scheme is designed for the proposed system. The simulation results show that the proposed scheme with the developed receiver can offer nearly the same performance gain as conventional SM, whereas the unintended receiver can hardly detect the information correctly. Moreover, the average bit error rate (BER) is analyzed, which also validates our simulation results.