Security Analysis in Correlated Nakagami-m Fading Channels with Diversity Combining

This paper investigates the effect of exponential antenna correlation on the secrecy performance of Nakagami-m fading correlated channels in the presence of an eavesdropper. Diversity combining techniques are imposed to reduce the effect of that exponential correlation. The closed-form analytical expressions (CFAEs) for the ergodic secrecy capacity (EGC), probability of non-zero secrecy capacity (PNZSC) and the secure outage probability(SOP) are derived to facilitate the investigation clearly. Our results show that the effect of exponential antenna correlation in Nakagami-m fading channel significantly affects the security. But the antenna diversity is the best solution to reduce that effect maintaining a tradeoff between the number of antennas and the intensity of correlation. Finally, the validity of analytical expressions are checked via Monte-Carlo simulations.