K band is a portion of the electromagnetic spectrum in the microwave range of frequencies ranging between 12 to 63 GHz. K band between 18 and 26.5 GHz is absorbed easily by water vapor (H2O resonance peak at 22.24 GHz, 1.35 cm). The letter K comes from the German language word kurz, meaning "brief" or "short".
The NATO K-band is defined as frequency band between 20–40 GHz (7.5-15 mm).
See also
- Ka band: K-above band, 18–40 GHz for radar and communications
- Ku band: K-under band, 12–18 GHz for satellite communications