Performance of APD-Based Amplify-and-Forward Relaying FSO Systems over Atmospheric Turbulence Channels

Abstract

This paper proposes and theoretically analyzes the performance of amplify-and-forward (AF) relaying free-space optical (FSO) systems using avalanche photodiode (APD) over atmospheric turbulence channels. APD is used at each relay node and at the destination for optical signal conversion and amplification. Both serial and parallel relaying configurations are considered and the subcarrier binary phase-shift keying (SC-BPSK) signaling is employed. Closed-form expressions for the outage probability and the bit-error rate (BER) of the proposed system are analytically derived, taking into account the accumulating amplification noise as well as the receiver noise at the relay nodes and at the destination. Monte-Carlo simulations are used to validate the theoretical analysis, and an excellent agreement between the analytical and simulation results is confirmed.