Radio Frequency Bands

Radio Frequency Spectrum
The Atlantic City Conference of the International Telecommunication Union (ITU) in 1947 subdivided the radio frequency spectrum. Each subdivision of the radio frequency spectrum has its own propagation characteristics through the land, water and atmospheric envelope covering the earth. For example it has been experimentally observed that VHF usually penetrates the ionosphere and are lost into space, while the HF (short wave) are reflected back from the ionosphere.

3-30 KHz	VLF (Very Low Frequencies)
30-300 KHz	LF (Low Frequencies)
300-3000 KHz	MF (Medium Frequencies)
3000-30,000 KHz (3-30MHz)	HF (High Frequencies or short waves)
30-300 MHz	VHF (Very High Frequencies)
300-3000 MHz	UHF (Ultra High Frequencies)
3000-30,000 MHz	SHF (Super High Frequencies)
30-300 GHz	EHF (Extreme High Frequencies)