Information theoretic analysis of a dual-hop fixed gain AF based mixed RF-FSO system

In this paper, information theoretic analysis of the amplify-and-forward based mixed radio frequency-free space optical (RF-FSO) cooperative communication system is performed. The RF link is assumed to be Nakagami-m distributed and the FSO link is modeled by the Gamma-Gamma distributed turbulence, pointing error, and path loss. Novel finite power series analytical expressions of the average channel capacity are derived for the considered asymmetric system under simultaneous optimal power and rate adaptation (OPRA) and truncated channel inversion with fixed rate (TCIFR) adaptive transmission policies in terms of Extended Bivariate Generalized Meijer-G function. Simulation results validate the proposed analysis. The effect of atmospheric conditions and pointing errors is analyzed by using the average channel capacity expressions. It is observed that the OPRA capacity outperforms TCIFR capacity.