Performance Analysis of SM-based Hybrid MIMO FSO/RF System

Free space optical (FSO) communication has emerged as an alternative technology to conventional RF technology for the abundance of unregulated spectrum, high immunity to electromagnetic interference and high security. But unlike RF technology, it's highly sensitive to atmospheric turbulence. A communication system comprising of both FSO and RF technologies can reap benefits from both. We propose a hybrid SM-based FSO/RF model to increase the throughput and reliability of the system. The FSO channel is modelled as Malaga-$\mathcal{M}$ distributed and RF channel is assumed to be Nakagami-$m$ distributed. Spatial modulation (SM) at the transmitter is incorporated to increase the spectral efficiency and selection combiner is employed at the receiver to achieve higher diversity order. Monte Carlo simulation of ergodic capacity and symbol error rate (SER) has been carried out.