부산대학교 도서관

In this paper, we analyze a subcarrier intensity modulation (SIM) based relayed free space optical (FSO) system assuming independent but not necessarily identically distributed (i.n.i.d) Gamma-Gamma turbulence channels. System employs a channel-state-information-assisted (CSI-assisted) amplify and forward (AF) relay. We derive the moment generating function (MGF) of the end-to-end signal to noise ratio (SNR) of the system and using the novel MGF, accurate closed-form expressions for capacity under different adaptive transmission schemes such as optimal rate adaptation (ORA) and channel inversion with fixed rate (CIFR) are derived. Further, we derive closed form expression for average symbol error rate (SER) of M-ary phase shift keying (MPSK) modulation schemes in terms of Meijer's G-function.