Coded cooperation over wireless optical links in weak turbulence with misalignment fading

The outage behaviour of a free-space optical (FSO) cooperative communication system with coded cooperation diversity is analyzed. The coded cooperation, through the transmission of incremental redundancy, provides the combined gain of cooperative signalling and channel coding. In this paper, we consider a two user based system model, where each user transmits its data as well as acts as the cooperative partner for the other user. The FSO links in weak atmospheric turbulence regime are modelled with log normal fading distribution. The outage analysis of the coded cooperative diversity is performed in presence of zero-boresight misalignment errors in the receiver planes. Specifically, the new closed form expression for outage probability is derived for each user. Moreover, the effect of distance dependent path loss factor is also considered in the analysis.