Relay selection in FSO systems with all-optical relaying over Gamma-Gamma turbulence channels

In this paper, we consider an all-optical multi-relay FSO system and investigate its outage performance over Gamma-Gamma atmospheric turbulence channels. To avoid strict synchronization requirements among relay nodes, we employ relay selection and use only the selected relay in the relaying phase. The outage probability results indicate that relay selection demonstrates significant improvements over the conventional scheme with all relays active.