Kubånd

Kubånd, or Ku-band, is a portion of the microwave spectrum allocated for satellite communications. It covers roughly 12 to 18 gigahertz, with uplink and downlink shared by ground stations and satellites; in many systems uplink commonly uses about 14 GHz and downlink about 12 GHz, though allocations vary by region.

Applications include direct-to-home television (DTH), satellite internet (VSAT), maritime and aeronautical communications, and military uses. The band enables relatively small dish antennas compared with lower-frequency bands, typically 0.6 to 1.2 meters for residential DTH, though larger antennas are used for higher data rates or fringe areas. The use of circular polarity is common to reduce cross-polarization interference.

Operational considerations arise from the high frequency, making signals more susceptible to rain fade and atmospheric attenuation, especially near the upper edge of the band. The need for a clear line of sight and stable pointing makes installation more demanding than lower bands. It coexists with other microwave bands such as C-band and Ka-band, and often uses digital modulation schemes like DVB-S and DVB-S2 for efficient transmission.

History and regulation: The Ku-band was allocated by the ITU in the 1960s and 1970s for satellite communications. The standard has evolved with modern transponders, high-definition and broadband services, and satellite internet developments.