  In this work we analyse three quantum communication schemes for the
generation of Gaussian entanglement between two ground stations. Communication
occurs via a satellite over two independent atmospheric fading channels
dominated by turbulence-induced beam wander. In our first scheme the
engineering complexity remains largely on the ground transceivers, with the
satellite acting simply as a reflector. Although the channel state information
of the two atmospheric channels remains unknown in this scheme, the Gaussian
entanglement generation between the ground stations can still be determined. On
the ground, distillation and Gaussification procedures can be applied, leading
to a refined Gaussian entanglement generation rate between the ground stations.
We compare the rates produced by this first scheme with two competing schemes
in which quantum complexity is added to the satellite, thereby illustrating the
trade-off between space-based engineering complexity and the rate of
ground-station entanglement generation.
