The impact of channel imperfection and multiple eavesdroppers on security of dual-signal selection in AF-relay systems

This paper investigates the impact of channel imperfection and multiple eavesdroppers on the secrecy performance of dual-signal selection in amplify and forward-relay systems. This paper derives the lower-bound closed-form expressions of the dual-signal selection for the secrecy outage probability. This work also derives the asymptotic secrecy outage probability expressions of the dual-signal selection for four scenarios and quantifies the secrecy diversity order. Using the asymptotic analysis, we observe that the dual-signal selection provides the secrecy diversity order gain of UM_T compared to the conventional relay-signal scheme in the presence of channel imperfection. Finally, we find that the parameters of eavesdropper such as E and M_E do not significantly affect the secrecy performance of the dual-signal selection.