Radio (wireless) communication is realized through electromagnetic waves, which we describe using frequency or wavelength. The product of frequency and wavelength equals the speed of light, i.e. the propagation velocity of an electromagnetic wave in a vacuum.
The millimeter wave (mmWave), also known as the millimeter band, is the band of the radio frequency spectrum with wavelengths between 10 millimeters (30 GHz) and 1 millimeter (300 GHz); considered to deliver faster, higher-capacity 5G services.
