  To provide high data rate aerial links for 5G and beyond wireless networks,
the integration of free-space optical (FSO) communications and aerial platforms
has been recently suggested as a practical solution. To fully reap the benefit
of aerial-based FSO systems, in this paper, an analytical channel model for a
long-range ground-to-air FSO link under the assumption of plane wave optical
beam profile at the receiver is derived. Particularly, the model includes the
combined effects of transmitter divergence angle, random wobbling of the
receiver, jitter due to beam wander, attenuation loss, and atmospheric
turbulence. Furthermore, a closed-form expression for the outage probability of
the considered link is derived which makes it possible to evaluate the
performance of such systems. Numerical results are then provided to corroborate
the accuracy of the proposed analytical expressions and to prove the
superiority of the proposed channel model over the previous models in
long-range aerial FSO links.
