VHF (Very High Frequency) band is the band of the radio spectrum extending from 30 MHz to 300 MHz, i.e. from 10 to 1 m in electromagnetic wavelength.
UHF (Ultra High Frequency) band is the term for radio frequencies between 300 MHz and 3,000 MHz, i.e. wavelengths from 1 m to 0.1 m. The upper part belongs more generally to the technical domain of “microwaves” which extends from 1 GHz (1,000 MHz) to 1,000 GHz. Its use developed with the saturation of the VHF band for fixed or mobile radiotelephony and television applications, as suitable components became available.
UHF and VHF frequencies are mainly propagated in direct view. Their wavelengths are suitable for mobile or fixed radiotelephone links with simple non-directional antennas and low powers, favorable for military, land, sea and aeronautical links.
Initially, the width of the VHF band with the invention of the Yagi antennas allowed the realization of antennas for the first radars, today used for television, FM, amateur radio, fixed telemetry or satellite links. Following the arrival of UHF, the band above 1,000 MHz was used for radars, then for radio-relay systems, GPS or mobile phone satellite links, and more recently for GSM mobile phones and Wi-Fi or Bluetooth links.