Cband

C-band refers to a portion of the microwave radio spectrum and is an informal name used in multiple contexts. In ITU-R terminology, C-band generally covers roughly 4 to 8 GHz of the spectrum. The most widely used segment for satellite communications lies around 3.7–4.2 GHz for downlink and 5.925–6.425 GHz for uplink, a pairing known as the C-band satellite frequencies. This band supports satellite television distribution, data links, and fixed or mobile satellite services.

Beyond satellites, C-band allocations have been used for terrestrial microwave links and fixed wireless access in some regions. In the context of mobile communications, the term C-band is also employed to describe mid-band spectrum used for 5G deployments, commonly centered on 3.7–4.2 GHz, with some regions extending into 4.4–5.0 GHz. Exact boundaries and usage vary by country and regulator.

Technical considerations: C-band offers a balance between obtainable bandwidth and propagation characteristics. It requires dish antennas for satellite services and experiences less rain-fade than higher-frequency bands such as Ku- and Ka-band, though more than lower bands. The band is subject to ITU coordination and national licensing, and may be shared with or protected from interference by radar and other services in certain regions.

History and role: The band has been in use for satellite communications since the 1960s–70s and remains important for traditional satellite television and international data transmission, while also being leveraged for evolving terrestrial wireless services in various regulatory environments.