What is Ku-band?
Ku-band (K-under) occupies the 12–18 GHz frequency range, with commercial satellite uplinks at 14.0–14.5 GHz and downlinks at 11.7–12.75 GHz. It has been the workhorse of satellite communications since the 1970s and remains the dominant band for direct-to-home (DTH) television broadcasting globally — virtually all DTH dishes (DirecTV, Sky, Astra) receive Ku-band signals.
Advantages over Ka-band
Ku-band's lower frequency means the signal is less attenuated by rain and atmospheric water vapour — a crucial advantage for maritime vessels in tropical waters, terrestrial broadcast distribution, and mobile satellite applications where link margin must account for variable weather. The technology base for Ku-band is mature and widely deployed, with abundant ground equipment and competitive pricing from multiple manufacturers.
DTH broadcasting
Ku-band's regulatory allocation includes the BSS (Broadcasting Satellite Service) band (11.7–12.5 GHz in Europe), specifically designated for direct broadcast to small consumer dishes. The SES Astra satellites at 28.2°E and 19.2°E serve over 100 million DTH homes in Europe. Ku-band broadcast transponders (typically 33 or 54 MHz wide) can deliver dozens of SDTV or several HDTV/4K channels using DVB-S2 or DVB-S2X compression.
Maritime and aeronautical VSAT
Ku-band VSAT on ships (Inmarsat Fleet Broadband, KVH, Marlink, Speedcast) provides crew welfare internet and operational data connectivity. For aeronautical IFE, Ku-band was the early standard (Panasonic eXConnect, Intelsat) before Ka-band displaced it for new aircraft programmes. Ku-band phased-array terminals for aeronautical use are now competing with Ka-band systems for airline contracts.