V-band

V-band refers to the portion of the radio-frequency spectrum from approximately 40-75 GHz and is commonly classified within the extremely high frequency (EHF) range. In satellite communications, V-band is of interest for very high-capacity systems, particularly feeder links and future broadband networks that need access to wide blocks of spectrum beyond the traditional C-band, Ku-band, and Ka-band allocations.

The principal attraction of V-band is bandwidth. As satellite systems move toward higher throughput, large spot-beam networks, and dense frequency reuse, gateway links may need to carry very large aggregate data rates. V-band can provide access to wider bandwidths and narrower antenna beams, allowing high-capacity links between gateways and satellites. The small wavelength also makes compact high-gain antennas possible, although the required pointing accuracy becomes more demanding.

V-band propagation is challenging. Rain attenuation, cloud attenuation, gaseous absorption, scintillation, and depolarization can all be significant. The band includes frequencies where atmospheric oxygen absorption is strong, particularly around 60 GHz, which can severely limit long Earth-space paths but may also reduce interference over terrestrial paths. Because of these effects, V-band satellite systems generally require careful link design, fade mitigation, gateway diversity, adaptive coding and modulation, power control, and accurate site selection.

V-band is less mature in routine commercial satellite operation than C-band, Ku-band, and Ka-band, but it is increasingly important in filings and designs for high-throughput satellites and non-geostationary constellations. It is most often discussed as a way to relieve congestion in lower bands and to provide feeder-link capacity rather than as a universal replacement for user links. Interference coordination, equipment cost, atmospheric availability, and regulatory constraints remain important considerations.