Performance Analysis of Mixed FSO/RF System for Satellite-Terrestrial Relay Network

This paper analyzes the performance of a satellite-terrestrial free-space optical (FSO)/millimeter wave (MMW) radio frequency (RF) relaying system with amplify-and-forward (AF) and decode-and-forward (DF) relaying. The M$\acute{\text {a}}$laga ($\mathcal {M}$) distribution with pointing error impairments and the multi-cluster fluctuating two-ray (MFTR) fading model are introduced to characterize the FSO link for both heterodyne detection (HD) and indirect modulation/direct detection (IM/DD) and MMW link, respectively. Therefore, the precise closed-form expression of end-to-end signal-to-noise ratio (SNR) for the outage probability (OP), average bit error rate (BER), ergodic capacity (EC) and effective capacity (EFC) is derived. In addition, we present an asymptotical result analysis for the OP and average BER at high SNR in terms of simple functions. Finally, we employ Monte-Carlo (MC) simulation results to verify all our analytical results.