- Inmicrowave technology, the U-band occupies the frequency range between 40 GHz and 60 GHz according to ITU specifications. In radar technology, this range is occupied by the V-band from 40 GHz to 75 GHz.
- In optical networks, the transmission ranges are defined in the ITU grid. There are six wavelength ranges. The U-band, "U" stands for Ultralong Wavelength, is the wavelength band with the longest wavelengths between 1,625 nm and 1,675 nm. It is defined in the ITU grid and lies in the third telecommunications window. Below the U band is the L (Long) band.