Performance Analysis of FSO Links over Unified Gamma-Gamma Turbulence Channels

In this work, we present a unified performance analysis of a free-space optical (FSO) link that accounts for pointing errors and both types of detection techniques (i.e. intensity modulation/direct detection as well as heterodyne detection). We, then, present unified exact closed-form expressions for various statistical characteristics of the end-to-end signal-to-noise ratio (SNR) of a single link FSO transmission system. We capitalize on these unified results to offer unified exact closed-form expressions for various performance metrics. Additionally, we derive the asymptotic results for all the expressions derived earlier in the high SNR regime in terms of simple elementary functions. We also derive new asymptotic expressions for the ergodic capacity in the low as well as high SNR regimes in terms of simple elementary functions via utilizing moments. All the presented results are verified via computer-based Monte-Carlo simulations.