Spectral efficiency performance of small-aperture terminals in NGSO satellite links

A non-geostationary orbit (NGSO) satellite system is currently being introduced by O3b Networks and this has generated interest in high-data rate services using NGSO satellites. In this paper the spectral efficiency performance of a general NGSO link is analyzed when it is used with small-aperture earth terminals. This analysis is applicable to a general NGSO satellite system operating in the Ka-band. This analysis takes into consideration the pertinent International Telecommunications Union (ITU) Radio Regulations (RR) emission constraints that allow NGSO systems to coexist with GSO systems. It is shown that the spectral efficiency available from small-aperture satellite links depends on the location of the earth terminal: higher latitudes and smaller differences between the longitudes of the earth terminal and the satellite give higher spectral efficiency levels.