Performance analysis of amplify and forward serial relaying coherent OFDM FSO system based on M distribution

Abstract

In this paper, the performance of amplify and forward (AF) serial relaying coherent orthogonal frequency division multiplexing (OFDM) free space optical communication (FSO) system is analyzed over an aggregated atmospheric turbulence attenuation channel, which considers path loss, pointing error and M distribution channel. In this FSO system, it is assumed that channel state information (CSI) of transmitter and receiver is known, quadrature amplitude modulation (QAM) is used as the subcarrier mapping mode of OFDM. With the help of Meijer’s G function, the closed-form expressions of outage probability and average symbol error probability (ASER) for the FSO system under consideration are derived. The effects of subcarriers, the number of hops and turbulence intensity on the performance of coherent OFDM FSO systems are analyzed through simulation.