The IEEE K-band is a portion of the radio spectrum in the microwave range of frequencies from 18 to 27-Gigahertz (GHz). The range of frequencies in the center of the K-band between 18- and 26.5-GHz is absorbed by water vapor in the atmosphere due to its resonance peak at 22.24-GHz, 1.35 cm (0.53 in). Therefore these frequencies experience high atmospheric attenuation and cannot be used for long distance applications. For this reason the original K-band has been split into three bands, Ka-band, K-band, and Ku-band as detailed below.
|18 – 27 GHz|
|1.67 – 1.11 cm|
The K stands for Kurz which stems from the German word for short.
Because of the water vapor absorption peak in the center of the band, the IEEE K-band is conventionally divided into three sub-bands:
The Radio Regulations of the International Telecommunication Union (ITU) allow amateur radio and amateur satellite operations in the frequency range 24.000-GHz to 24.250-GHz, which is known as the 1.2-centimeter band. It is also referred to as the K-band by AMSAT.