Very high frequency (VHF) is the ITU designation for the range of radio frequency electromagnetic waves (radio waves) from 30 to 300 megahertz (MHz), with corresponding wavelengths of ten meters to one meter. Frequencies immediately below VHF are denoted high frequency (HF), and the next higher frequencies are known as ultra high frequency (UHF).
Common uses for radio waves in the VHF band are FM radio broadcasting, television broadcasting, two way land mobile radio systems (emergency, business, private use and military), long range data communication up to several tens of kilometers with radio modems, amateur radio, and marine communications. Air traffic control communications and air navigation systems (e.g. VOR & ILS) work at distances of 100 kilometres (62 mi) or more to aircraft at cruising altitude.
In North America, most of South America and many other parts of the world, VHF Band I was used for the transmission of analog television. As part of the worldwide transition to digital television most countries require broadcasters to transmit television in the VHF range using digital rather than analog format.
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