  Effective integration of terrestrial and non-terrestrial segments is one of
the key research avenues in the design of current and future wireless
communication networks. To this aim, modern communication-satellite
constellations intend to attain sufficiently high throughput in terms of bit
rate per unit area on the ground by rather aggressive patterns of spatial
frequency reuse. This goal calls for on-board narrow-beam antennas, whose size
turns out to be in many cases incompatible with the size/mass and accommodation
constraints of the hosting satellite. This paper investigates the attainable
performance of large distributed arrays of antennas implemented as the ensemble
of a few to many simpler sub-antennas of smaller sizes, carried by one (small)
satellite each. The sub-antennas can in their turn be implemented like
(regular) 2D arrays of simple radiating elements, realizing an overall
(distributed) antenna architecture that we call "Formation of Arrays" (FoA).
The satellites that implement this radiating architecture need to be relatively
close to each other and constitute a formation of flying objects, to be
coordinated and controlled as a whole. In this paper, we develop a theoretical
analysis of an FoA antenna, and we show how to take advantage of this new
technology to improve network throughput in a multi-beam S-band mobile
communication network with low-earth or geostationary orbiting satellites
directly providing 5G-like communication services to hand-held user terminals.
