Performance analysis of multi-hop free space optical communications with pointing errors

This paper investigates the performance of multi-hop free space optical (FSO) communications with pointing errors. A statistical model for the optical intensity fluctuation at the receiver due to the combined effects of atmospheric turbulence-induced fading, misalignment fading and pass-loss is presented. For given weather and misalignment conditions, a close-form analytical expression for the end-to-end outage probability of serial decode-and-forward (DF) multi-hop FSO communication is derived. Numerical results show that the serial DF multi-hop transmission is a promising technology to increase the performance of FSO communications. Moreover, the derived analytical expression can provide very well approximations to the simulation results.