Ultra high frequency (UHF) is the ITU designation
for radio frequencies in the range between 300 megahertz (MHz) and 3 gigahertz
(GHz), also known as the decimetre band as the wavelengths range from one meter
to one tenth of a meter (one decimeter). Radio waves with frequencies above the
UHF band fall into the super-high frequency (SHF) or microwave frequency range.
Lower frequency signals fall into the VHF (very high frequency) or lower bands.
UHF radio waves propagate mainly by line of sight; they are blocked by hills
and large buildings although the transmission through building walls is strong
enough for indoor reception. They are used for television broadcasting, cell
phones, satellite communication including GPS, personal radio services
including Wi-Fi and Bluetooth, walkie-talkies, cordless phones, and numerous
other applications.
The IEEE defines the UHF radar band as frequencies
between 300 MHz and 1 GHz.[1] Two other IEEE radar bands overlap the ITU UHF
band: the L band between 1 and 2 GHz and the S band between 2 and 4 GHz.
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