Performance of Space-Shift Keying With Buffer-Aided Amplify-and-Forward Relaying

In this paper, we study a space-shift keying (SSK) based dual-hop relaying system. We assume that the relay node (RN) possesses an information buffer and propose an adaptive transmission scheme in which the system adaptively chooses the source–relay or the relay–destination links to transmit information in each time slot. We obtain an exact closed-form expression of the average bit-error probability for the system in which the source node has two transmit antennas. For the system with arbitrary number of transmit antennas, an upper bound is provided, and it is shown that the proposed scheme can achieve a diversity order of two by using the asymptotic analysis. The delay of the information packets at the RN is investigated, and two link adaptation schemes are proposed to reduce the average packet delay. Numerical results validate our analysis and show that the proposed scheme can significantly improve the system performance, as compared to the conventional relaying scheme.