C band ("compromise" band) is a portion of electromagnetic spectrum in the microwave range of frequencies ranging from 4 to 6 GHz.
C band is primarily used for satellite communications, normally downlink 3.7–4.2 GHz horizontal polarization, uplink 5.9–6.4 GHz vertical polarization, usually 24 36 MHz transponders on board a satellite.
The applications include full-time satellite TV networks or raw satellite feeds, although subscription programming also exists. There are more than 20 C-band satellites in Geosychronous orbit serving North America, which provide more than 250 video channels and 75 audio services. Typical antenna sizes on C-band capable systems range from 7.5 to 12 feet (2 to 3.5 m).
This contrasts with direct broadcast satellite, which is a completely closed system used to deliver subscription programming to small satellite dishes connected to proprietary receiving equipment.
C band is highly associated with TVRO satellite reception systems or "big dish" systems. Larger antennas and more expensive receivers, C band usually provides better video quality and is less affected by rain attenuation than the Ku band.
The NATO C band is defined as frequency band between 0.5 and 1 GHz (0.3 and 0.6 m).
See also