Two-way all-optical AF relaying FSO systems over Malaga (M) channels with pointing errors

Two-way transmission protocol is an efficient method to overcome the spectral loss incurred due to half-duplex communication. In this paper, we propose to implement two-way transmission in an amplify-and-forward (AF) relaying free-space optical (FSO) system utilizing an AF relay with optical amplifier. The performance of the proposed FSO system using subcarrier intensity modulation (SIM) with intensity modulation/direct detection (IM/DD) over independent but not necessarily identically distributed (i.n.i.d) Malaga (M) atmospheric turbulence channels in presence of pointing errors is studied. Exact closed-form expressions for the moment generating function (MGF) and cumulative distribution function (CDF) of the end-to-end signal-to-noise ratio (SNR) are obtained in terms of extended generalized bivariate Meijer's G-functions (EGBMGF). Capitalizing on these new results, we derive exact closed-form expressions for various performance metrics of the considered FSO system including the outage probability, the average bit error rate (ABER), and the ergodic achievable-rate. All analytical results are thoroughly confirmed by Monte-Carlo (M-C) simulations.