Spectrum management is the process of regulating the use of radio frequencies to promote efficient use and gain a net social benefit. The term radio spectrum typically refers to the full frequency range from 1 Hz to 3000 GHz (3 THz) that may be used for wireless communication. Increasing demand for services such as mobile telephones and many others has required changes in the philosophy of spectrum management. Demand for wireless broadband has soared due to technological innovation, such as 3G and 4G mobile services, and the rapid expansion of wireless internet services.
Since the 1930s, spectrum was assigned through administrative licensing. Limited by technology, signal interference was once considered as a major problem of spectrum use. Therefore, exclusive licensing was established to protect licensees' signals. This former practice of discrete bands licensed to groups of similar services is giving way, in many countries, to a "spectrum auction" model that is intended to speed technological innovation and improve the efficiency of spectrum use. During the experimental process of spectrum assignment, other approaches have also been carried out, namely, lotteries, unlicensed access, and privatization of spectrum.
Most recently, America has been moving toward a shared spectrum policy, whereas Europe has been pursuing an authorized shared access (ASA) licensing model. President Obama made shared spectrum the policy of the United States on 14 June 2013, following recommendations from the President's Council of Advisors for Science and Technology (PCAST) which advocated the sharing of (uncleared) federal radio spectrum when unused at a place and time provided it does not pose undue risks. In line with this guidance, as of Dec 2014 the FCC was extending the limited success of television band spectrum sharing (TV white space) into other bands, significantly into the 3550–3700 MHz US Navy radar band via a three tier licensing model (incumbent, priority, and general access).
Most countries consider RF spectrum as an exclusive property of the state.
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A mobile phone (or cellphone) is a portable telephone that can make and receive calls over a radio frequency link while the user is moving within a telephone service area, as opposed to a fixed-location phone (landline phone). The radio frequency link establishes a connection to the switching systems of a mobile phone operator, which provides access to the public switched telephone network (PSTN). Modern mobile telephone services use a cellular network architecture and therefore mobile telephones are called cellphones (or "cell phones") in North America.
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