Radio frequencies are useful for transmission of signals over long distances and their propagation is in accordance with laws of physics. Compared to human voice (sound), which fades after a few meters, the same sound signal can be carried over a radio frequency to travel hundreds of kilometers. The radio frequency (RF) spectrum is a limited, natural resource that is available equally to every country. The RF spectrum starts from 9KHz with the upper limit extending to 3000GHz, above which lie the optical frequencies
Spectrum management is the combination of technical and administrative procedures necessary to ensure orderly and efficient operations of various radio communication services in a country, without causing harmful interference. Assignment of appropriate frequencies for various applications is the basic function of spectrum management. The activities for this purpose, among others, include the analysis of potential interference problems, keeping an efficient database of frequency assignments, planning the future use of the spectrum. Radio monitoring is another important function to protect the assigned frequency from interference by others as well as to ensure that it does not cause interference to other users.
As radio frequencies are not confined to geographical boundaries of countries, the spectrum management functions are international in character and have to perform in accordance with Radio Regulations of the International Telecommunication Union (ITU), which is the specialized agency of the United Nations for global telecommunication matters.