Performance Analysis of RoFSO Links with Diversity Reception for Transmission of OFDM Signals Under Correlated Log-normal Fading Channels

Freespaceoptical(FSO)communicationhasbeenreceivinggrowingattention with recent commercialization successes as a cost-effective and high bandwidth optical access technique. Meanwhile, FSO communication has been regard as an attractive solution to bridging the gap between the wireless communications and optical fiber communications. However, a significant performance degradation in FSO communication system due to the atmospheric turbulence impairs the transmission performance improvement. FSO system employing the spatial diversity technique can be used to mitigate the effect of turbulence and improve the transmission performance. In this paper, a novel analytical approach is presented to evaluate the transmission performance of OFDM-FSO system with diversity reception considering effect of channel correlation.Adetailed mathematical model for OFDM-FSO system over turbulent channel modeled by correlated Log-normal distribution is provided. Then, We derive the signal-to-noise ratio (SNR), bit error ratio (BER) and outage probability expressions taking into account the diversity combining schemes (i.e. MRC, EGC), effects of atmospheric turbulence, channel correlation and aperture size of receiver lens. The results of this