Capacity of spectrum available for unmanned-aircraft command and control links

The amount of radio spectrum available for command and control (C2) radio links of unmanned aircraft (UA) systems (UAS), and the effectiveness with which that spectrum is used, will strongly affect the eventual number of remotely piloted UAS that can safely operate within U.S. airspace. In this paper we analyze several possible methods for utilizing available UAS C2 spectrum as efficiently as possible. We assess the potential impact of various spectrum-management techniques, including synchronized time-division duplexing and two- and three-dimensional zonal frequency planning, that have been proposed for standalone terrestrial C2 links that will use licensed radio spectrum.