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The RF electromagnetic spectrum is an aspect of the physical world which, like land, water, and air, is subject to usage limitations. Use of radio frequency bands of the electromagnetic spectrum is regulated by governments in most countries, in a Spectrum management process known as frequency allocation or spectrum allocation. Like weather and pollution, radio propagation does not stop at national boundaries. Giving technical and economic reasons, governments have sought to harmonise the allocation of RF bands and their standardisation.

A number of forums and standards bodies work on standards for frequency allocation, including:

High-demand sections of the electromagnetic spectrum may sometimes be allocated through auctions.

International conventions

The range of "radio frequencies" is a matter of international convention. The separation of countries into the three formal ITU RF allocation regions is the source of different RF allocation among continents. The definition of the ITU Regions (capital R, for ITU-R Regions) is based largely on longitude. According to ITU Radio Regulations (RR) section 5.1: Member States assign licences to stations and Article 5 of the ITU RR allocates frequencies to services (such as Broadcasting and Mobile). The ITU divides the world into five administrative regions:

  • A- the Americas,
  • B- Western Europe,
  • C- Eastern Europe and Northern Asia,
  • D-Africa and
  • E-Asia and Australasia.

The ITU also categorises states into three Radio regulatory Regions:

  • Region 1: Europe, Middle East, Africa, the former Soviet Union, including Siberia; and Mongolia;
  • Region 2: North and South America and Pacific (East of the International Date Line);
  • Region 3: Asia, Australia and the Pacific Rim (West of the International Date Line).

So, at the very least the RF allocations fundamentally differ between Continents. Longitude may traverse continents, for example, Meridian E401 crosses Europe (Russia), Asia (Middle East) and Africa. The separation may echo the 'Euro-sphere' (including Africa, Middle East and Russia) as Region 1, the American continent as Region 2, and Asia as Region 3.

The division between Europe and the 'other regions' is the root of the different RF allocations in the ITU Radio Regulations, and standards around the world. Based mainly on George A. Codding, Dr. Haim Mazar [1] (vice chairman of ITU-R Study group 1 [2])details how and why there are three separate Regions. Through the efforts of the ITU and its predecessor, the International Radio Telegraph Union, most of the usable part of the spectrum has been divided among various radio services (Codding 1959:80). These are the phases of the longitude separation into three ITU Regions:

-In 1906 in Berlin, 29 countries under the guidance of the Germans, drew up an International Radiotelegraph Convention and annexed the Radio Regulations, following the example of the International Telegraph Union (Codding and Rutkowski 1982:13).

─ In 1927 at the Washington ITU conference, different allocations across the Atlantic were discussed; in particular concerning frequencies above 25 MHz. European countries held that all frequencies between 25 and 200 MHz should be allocated on a worldwide basis for specific services. However countries in the rest of the Western Hemisphere expressed opposition to this view. They first pointed out that the countries of Europe and the Western Hemisphere (America) were using these frequencies for different purposes; secondly, they considered that the use of frequencies above 25 MHz was still in such an experimental state that only temporary allocations of these frequencies were advisable (Codding 1959:82). Therefore, for the first time, it appeared to be a case of West versus East: the US against Europe. Europe wanted worldwide allocation, and America wanted to operate the new RF bands above 25 MHz.

─ The Brussels 1928 ITU conference established the division into distinct regions, by confirming there would be a different channel separation in AM broadcasting: 9 kHz in Europe and 10 kHz in America (Codding 1959:93). The only contentious issue raised in the American ‘Rio de Janeiro 1981 agreement’ was whether to adopt the 9 kHz channel spacing common to the rest of the world, or to remain with the 10 kHz spacing in the Americas; it opted for the latter (Codding and Rutkowski 1982:52). The 10 kHz versus the 9 kHz channel separation of AM broadcasting is the first major difference between Europe and America; it remains until today 29 October 2008.

─ The ITU conference held in Madrid in 1932 divided the RF above 30 MHz into two parts, a European region and 'other regions' (Codding 1959:84). For the European region specific permanent bands were allotted to meteorological aids, TV, broadcasting, air services, amateurs, and fixed and mobile services. The American countries annexed an experimental table to the Cairo Radio Regulations for frequencies ranging between 30 to 300 MHz, as a possible guide for further development.

─ At the first combined ITU Administrative Telegraph and Telephone Conference and Administrative Radio Conference held in Cairo in 1938, two HF Broadcasting allocations were made in spite of the US' opposition to this initiative. The priorities in Europe (preferring nationalised collective broadcasting) and in the US (favouring the individual amateurs) are diverse; it is also interesting that the US has traditionally supported the Mobile service (land, aeronautical and maritime) over broadcasting. Thus, since 1938, dissimilar allocations have been introduced in Europe and America deriving from the different preferences on either side of the Atlantic.

─ The Atlantic City ITU conference (1947) continued the policy of breaking down allocations in non worldwide bands into regions (Codding 1959:85). In addition, the former twofold classification agreed upon in Cairo in 1938 was replaced by a threefold one: Region 1, approximately comprising Europe, Africa and the USSR; Region 2, the Western Hemisphere; and Region 3, the remainder of the World (Near East, Asia and Oceania).

─ The Cairo meeting (1938) allocated frequencies ranging until 200 MHz, and the Atlantic conference allocated those until 10,500 MHz (Codding 1959:85). Because their propagation characteristics were of a limited range, it was possible to prevent a major dispute by dividing some of the frequency in the 25 MHz to 200 MHz range into a European Region and 'other regions' (Codding and Rutkowski 1982:20). The Europeans were thus allowed to assign portions of the frequency band to specified services, and the US was free to be flexible in the use of the entire band.

See also

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