BER analysis of optical space shift keying in atmospheric turbulence environment

In this paper, we investigate the average BER (ABER) of space shift keying (SSK) in a free-space optical communication system under outdoor scenario. To obtain a tight upper bound on ABER of an arbitrary optical SSK (OSSK) system, a novel mathematical expression for the probability density function of difference between two Gamma-Gamma random variables is derived. It is observed that the ABER of OSSK system under strong and moderate atmospheric turbulence regime remains same. Additionally, it is found that the considered system performs poorer by 3 dB under weak turbulence regime as compared to the other two turbulence regimes.