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Spectrum management is the process of regulating the use of radio frequencies to promote efficient use and gain a net social benefit.〔Martin Cave, Chris Doyle, William Webb, ''Modern Spectrum Management'', Cambridge University Press, 2007 ISBN 0-521-87669-9〕 The term ''radio spectrum'' typically refers to the full frequency range from 3 kHz to 300 GHz 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, the President's Council of Advisors for Science and Technology (PCAST) advocated the sharing of (uncleared) federal radio spectrum when unused at a place and time provided it does not pose undue risks. Following PCAST's recommendations, President Obama made shared spectrum the policy of the United States on 14 June 2013 Shared Spectrum. 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) while Europe has been pursuing an authorized shared access (ASA) licensing model. ==Governments and spectrum management== Most countries consider RF spectrum as an exclusive property of the state. The RF spectrum is a national resource, much like water, land, gas and minerals. Unlike these, however, RF is reusable.〔(Radio spectrum as natural resource )〕 The purpose of spectrum management is to mitigate radio spectrum pollution and maximize the benefit of usable radio spectrum.〔(Application of the Public-Trust Doctrine and Principles of Natural Resource Management to Electromagnetic Spectrum )〕 The first sentence of the International Telecommunication Union (ITU) constitution fully recognises “the sovereign right of each State to regulate its telecommunication”. Effective spectrum management requires regulation at national, regional and global levels. Goals of spectrum management include: rationalize and optimize the use of the RF spectrum; avoid and solve interference; design short and long range frequency allocations; advance the introduction of new wireless technologies; coordinate wireless communications with neighbours and other administrations. Radio spectrum items which need to be nationally regulated: frequency allocation for various radio services, assignment of license and RF to transmitting stations, type approval of equipment (for countries out of the European Union), fee collection, notifying ITU for the Master International Frequency Register (MIFR), coordination with neighbour countries (as there are no borders to the radio waves), external relations toward regional commissions (such as CEPT in Europe, CITEL in America) and toward ITU. RF spectrum management is treated as a natural monopoly (to be compared to the concept of Jeremy Bentham and John Stuart Mill), as there is generally one regulator for any RF band. Discussions on central-planning versus market-based spectrum management are found at the 2008 PhD thesis (). 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「spectrum management」の詳細全文を読む スポンサード リンク
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