<P> High frequency ( HF ) is the ITU designation for the range of radio frequency electromagnetic waves ( radio waves ) between 3 and 30 megahertz ( MHz ) . It is also known as the decameter band or decameter wave as its wavelengths range from one to ten decameters ( ten to one hundred metres ) . Frequencies immediately below HF are denoted medium frequency ( MF ) , while the next band of higher frequencies is known as the very high frequency ( VHF ) band . The HF band is a major part of the shortwave band of frequencies , so communication at these frequencies is often called shortwave radio . Because radio waves in this band can be reflected back to Earth by the ionosphere layer in the atmosphere -- a method known as `` skip '' or `` skywave '' propagation -- these frequencies are suitable for long - distance communication across intercontinental distances . The band is used by international shortwave broadcasting stations ( 2.31 -- 25.82 MHz ) , aviation communication , government time stations , weather stations , amateur radio and citizens band services , among other uses . </P>
<P> High frequency ( HF ) is the ITU designation for the range of radio frequency electromagnetic waves ( radio waves ) between 3 and 30 megahertz ( MHz ) . It is also known as the decameter band or decameter wave as its wavelengths range from one to ten decameters ( ten to one hundred metres ) . Frequencies immediately below HF are denoted medium frequency ( MF ) , while the next band of higher frequencies is known as the very high frequency ( VHF ) band . The HF band is a major part of the shortwave band of frequencies , so communication at these frequencies is often called shortwave radio . Because radio waves in this band can be reflected back to Earth by the ionosphere layer in the atmosphere -- a method known as `` skip '' or `` skywave '' propagation -- these frequencies are suitable for long - distance communication across intercontinental distances . The band is used by international shortwave broadcasting stations ( 2.31 -- 25.82 MHz ) , aviation communication , government time stations , weather stations , amateur radio and citizens band services , among other uses . </P>
hf frequency bands used for aviation are between
hf frequency bands used for aviation are between
( 2.31 -- 25.82 MHz )
( 2.31 -- 25.82 MHz )