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      2016年ACCA(F8)考試模擬題(69)

      考試網(wǎng)  [ 2016年4月6日 ] 【

      ALLOCATION OF FREQUENCIES IN THE RADIO SPECTRUM

      In the United States the National Telecommunications and Information Administration (NTIA) has responsibility for assigning each portion of the

      radio spectrum (9 kHz to 300 GHz) for different uses. These assignments must be compatible with the rules of the International Telecommunications

      Union (ITU), to which the United States is bound by treaty. The current assignments are given in a wall chart (Reference 1) and may also be found

      on the NTIA web site (Reference 2). The list below summarizes the broad features of the spectrum allocation, with particular attention to those sections

      of scientific interest. The references should be consulted for details of the allocations in the frequency bands listed here, which in some cases are quite

      complex.

      REFERENCES

      1. United States Frequency Allocations, 1996 Spectrum Wall Chart, Stock No. 003-000-00652-2, U. S. Government Printing Office, P. O. Box

      371954, Pittsburgh, PA 15250-7954.

      2. http://www.ntia.doc.gov/osmhome/allochrt.html

      Frequency range Allocation

      9 - 19.95 kHz Maritime communication, navigation

      19.95 - 20.05 kHz Standard frequency and time signal (also at 60 kHz and 2.5, 5, 10, 15, 20, 25 MHz)

      20.05 - 535 kHz Maritime and aeronautical communication, navigation

      535 - 1605 kHz AM radio broadcasting

      1605 - 3500 kHz Mobile communication and navigation, amateur radio (1800-1900 kHz)

      3.5 - 4.0 MHz Amateur radio

      4.0 - 5.95 MHz Mobile communication

      5.95 - 13.36 MHz Mobile communication, amateur, short-wave broadcasting

      13.36 - 13.41 MHz Radioastronomy

      13.41 - 25.55 MHz Mobile communication, amateur, short-wave broadcasting

      25.55 - 25.67 MHz Radioastronomy

      25.67 - 37.5 MHz Mobile communication, amateur, short-wave broadcasting

      37.5 -38.25 MHz Radioastronomy

      38.25 - 50.0 MHz Mobile communication

      50.0 - 54.0 MHz Amateur

      54.0 - 72.0 MHz TV channels 2-4

      72.0 - 73.0 MHz Mobile communication

      73.0 - 74.6 MHz Radioastronomy

      74.6 - 76.0 MHz Mobile communication

      76.0 - 88.0 MHz TV channels 5-6

      88.0 - 108.0 MHz FM radio broadcasting

      108.0 - 118.0 MHz Aeronautical navigation

      118.0 - 174.0 MHz Mobile communication, space research, meteorological satellites

      174.0 - 216.0 MHz TV channels 7-13

      216.0 - 400.05 MHz Mobile communication

      400.05 - 400.15 MHz Standard frequency and time satellite (also 20 and 25 GHz)

      400.15 - 406.1 MHz Meteorological aids (radiosonde)

      406.1 - 410.0 MHz Radioastronomy

      410.0 - 470.0 MHz Mobile communication, amateur

      470.0 - 512.0 MHz TV channels 14-20

      512.0 - 608.0 MHz TV channels 21-36

      608.0 - 614.0 MHz Radioastronomy

      614.0 - 806.0 MHz TV channels 38-69

      806 -1400 MHz Mobile communication, navigation

      1400 - 1427 MHz Radioastronomy, space research

      1427 - 1660 MHz Various navigation and satellite applications

      1660 - 1710 MHz Radioastronomy, space research, meteorology

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