Performance analysis of free-space optics systems adopting multi-pulse PPM techniques in gamma-gamma channels for thermal noise limited systems

Atmospheric turbulence has a strong effect on the performance of the terrestrial free space optics system and there are many statistical models that are used to describe the atmospheric turbulence but gamma-gamma is shown to be the most suitable model in both weak and strong turbulence. In this paper, we adopt gamma-gamma model and use the characteristics of Meijer G function to get a closed form expression for the average symbol error rate of multi-pulse PPM under gamma-gamma fading channel. Next, we use our derived form to study the effect of atmospheric conditions, operating wavelength and modulation level on the system performance.