Millimeter wave technology (mmWaves) goes by several different names. You may have heard it referred to as millimeter band, high band 5G, or Extremely High Frequency (EHF) band by the International Telecommunication Union (ITU).
Regardless, all the names refer to a line-of-sight wireless communication technology that typically uses the portion of the spectrum with wavelengths between 4.2 millimeters (71 GHz) and 3.4 millimeters (86 GHz) to wirelessly transmit and receive high-frequency beams of radio waves carrying voice, video, and data information.
Millimeter waves deliver many benefits relative to traditional microwave and other legacy technology, including an enormous availability of frequency bands above 24 GHz.