Radio waves in the VHF band propagate mainly by line-of-sight and ground-bounce paths unlike in the HF band there is only some reflection at lower frequencies from the ionosphere ( skywave propagation). As part of the worldwide transition to digital terrestrial television most countries require broadcasters to air television in the VHF range using digital, rather than analog encoding. In the Americas and many other parts of the world, VHF Band I was used for the transmission of analog television. VOR and ILS) work at distances of 100 kilometres (62 mi) or more to aircraft at cruising altitude. Air traffic control communications and air navigation systems (e.g. Common uses for radio waves in the VHF band are Digital Audio Broadcasting (DAB) and 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. VHF radio waves propagate mainly by line-of-sight, so they are blocked by hills and mountains, although due to refraction they can travel somewhat beyond the visual horizon out to about 160 km (100 miles). 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.įrequencies immediately below VHF are denoted high frequency (HF), and the next higher frequencies are known as ultra high frequency (UHF). These six antennas are a type known as a Yagi antenna, which is widely used at VHF. VHF television antennas used for broadcast television reception.
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