Radio signals are transmitted through electromagnetic waves, also called radio waves, in radio communication system. The radio waves have a wide frequency range starting from a few ten kiloHertz (kHz) to several thousand Mega Hertz (MHz). This wide range frequencies is called the radio spectrum or RF spectrum.
The RF spectrum is classified according to the applications of the spectrum in different service areas. The classification of the RF spectrum is given in below table along with the associated applications in communication systems.
Classification of the Radio Frequency Spectrum
|Radio frequency range||Wavelength (meters) Mass||Class||Applicintions|
|10-30 kHz||3 x 104 - 104||Very Low Frequency (VLF)||Point-to-point communication (long Distance)|
|30-300 kHz||104 - 103||Low Frequency (LF)||Point-to-point communication (Long Distance) and Navigation|
|300-3000 kHz||103 - 102||Medium Frequency (MF)||Radio broadcasting|
|3-30 MHz||102 - 10||High Frequency (HF)||Overseas radio broadcasting,Point to Point Radio Telegraphy and Telephony|
|30-300 MHz||10 - 1.0||Very High Frequency (VHF)||FM brOadcast, television, and Radar|
|300-3000 MHz||1.0 - 0.1||Ultra heigh Frequency (UHF)||Television and navigation|
|3000-30,000 MHz||0.1 - 0.01||Super High Frequency (SHF)||Radar navigation and radio relays|