Satellite connectivity: actual technical parameters by orbital regime
Internet access via satellite link operates under physical principles that objectively determine its performance. End-to-end latency depends directly on orbital distance: a satellite in geostationary orbit GEO, located approximately 35,786 km above the equator, introduces a round-trip propagation delay of around 600 ms, which makes it incompatible with strict real-time applications but suitable for broadcast services and asymmetric access. Low Earth orbit LEO constellations, operating at altitudes between 500 and 1,200 km, reduce that delay to values of between 20 and 60 ms under nominal conditions, although continuous coverage requires a high orbital density constellation and inter-satellite handover mechanisms. One frequently misunderstood aspect is the shared capacity model. In broadband satellite systems, the bandwidth available in each coverage beam is distributed among all simultaneously active terminals. Capacity per user varies according to the actual load on the system, the multiplexing architecture employed, and the radio resource management implemented by the operator. This means that the announced nominal transfer rates correspond to conditions of low space segment occupancy, not to a guaranteed dedicated channel. Meteorological conditions constitute a technical limitation inherent to systems operating at elevated frequencies. Links in Ka-band and above are susceptible to rain attenuation, a phenomenon known as rain fade, whose magnitude depends on precipitation intensity, link elevation, and the climatic zone of the installation. Current systems incorporate adaptive power control and coding techniques to mitigate this effect, although they do not entirely eliminate service degradation under conditions of sustained heavy precipitation. MEO orbits, used primarily in GNSS positioning systems but also in some communications constellations, represent a compromise between the broad coverage of GEO and the low latency of LEO, with typical altitudes between 8,000 and 20,000 km. Each orbital architecture responds to a different set of mission requirements, and the selection among them entails technical trade-offs in latency, coverage, number of satellites required, and ground segment complexity. Rigorous evaluation of these parameters is the basis for determining which solution is appropriate for each institutional or operational use case.
NASSAT - Network Satellite Systems