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ACCA考試必做練習(xí)題1

考試網(wǎng)  [ 2016年4月16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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