Outage analysis of mixed RF/FSO cooperative systems with multiple antennas and apertures

We investigate the performance of dual-hop fixed gain amplify-and-forward (AF) relaying systems over Nakagami-m and double generalized Gamma (DGG) fading channels for mixed radio frequency/free space optical (RF/FSO) wireless systems. The FSO links account for pointing errors and two types of detection techniques. Our adopted turbulence and fading statistical models are the most general ones. To mitigate the effects of multipath fading and atmospheric turbulence the source and relay are equipped with multiple antennas. The relay equipped with single aperture for relaying the information over two FSO links. The destination has two receive apertures with selection combining (SC) scheme. With this new setup we derive closed form expressions for outage probability in terms of Meijer's-G and bivariate Fox-H functions. Our results explicitly demonstrate that using multiple antennas in the RF link and multiple apertures in the FSO link enhances the overall performance significantly.