Mitigating Jamming in FSO Cooperative Networks: A Buffer-Aided Relaying Approach

In this paper, we propose a buffer-aided relaying-based approach to counter the effects of jamming in free space optical (FSO) communication networks. An FSO cooperative system with a source node, a relay node, and a destination node is considered. The relay node consists of a finite-size buffer, and both relay and destination nodes are assumed to be affected by jamming. We use a Markov chain (MC) based approach to obtain the state transition matrix of the system, which is later used to evaluate the steady state probability of the proposed setup. A mixture of jamming and Gaussian noise is considered to evaluate the system's performance. Novel expressions of the outage probability and average bit error rate of the considered FSO system are obtained. The system's performance is then analyzed for different jamming powers and jamming probabilities. The proposed system is then compared with a non-buffer-aided (NBA) cooperative FSO system affected by a jammer; it is observed that the proposed buffer-aided FSO system significantly outperforms the NBA counterparts.