Multihop free space optical communications over turbulence channels with pointin

This paper proposes and analyzes the performance of the multihop free-space optical (FSO) communication links usinga heterodyne differential phase-shift keying modulation scheme operating over a turbulence induced fading channel. A novel statistical fading channel model for multihop FSO systems using channel-state-information-assisted and fixed-gain relays is developed incorporating the atmospheric turbulence, pointing errors, and path-loss effects. The closed-form expressions for the mome