SpectrumWiki

Radio spectrum allocations

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Examples: 88.5 MHz, 1350–1430 MHz, 2.4 GHz

400.15 MHz (400,150,000 Hz)

U.S. Federal Government Allocations

400.15 – 401 MHz

METEOROLOGICAL AIDS (radiosonde) US70

METEOROLOGICAL-SATELLITE (space-to-Earth)

MOBILE-SATELLITE (space-to-Earth) US319 US320 US324

SPACE RESEARCH (space-to-Earth) 5.263

Space operation (space-to-Earth)

5.264

ITU Region 1 Allocations

400.15 – 401 MHz

METEOROLOGICAL AIDS

METEOROLOGICAL-SATELLITE (space-to-Earth)

MOBILE-SATELLITE (space-to-Earth) 5.208A 5.208B 5.209

SPACE RESEARCH (space-to-Earth) 5.263

Space operation (space-to-Earth)

5.262 5.264

ITU Region 2 Allocations

400.15 – 401 MHz

METEOROLOGICAL AIDS

METEOROLOGICAL-SATELLITE (space-to-Earth)

MOBILE-SATELLITE (space-to-Earth) 5.208A 5.208B 5.209

SPACE RESEARCH (space-to-Earth) 5.263

Space operation (space-to-Earth)

5.262 5.264

ITU Region 3 Allocations

400.15 – 401 MHz

METEOROLOGICAL AIDS

METEOROLOGICAL-SATELLITE (space-to-Earth)

MOBILE-SATELLITE (space-to-Earth) 5.208A 5.208B 5.209

SPACE RESEARCH (space-to-Earth) 5.263

Space operation (space-to-Earth)

5.262 5.264

Footnotes

  • 5.208A   In making assignments to space stations in the mobile-satellite service in the frequency bands 137-138 MHz, 387 390 MHz and 400.15-401 MHz and in the maritime mobile-satellite service (space-to-Earth) in the frequency bands 157.1875-157.3375 MHz and 161.7875-161.9375 MHz, administrations shall take all practicable steps to protect the radio astronomy service in the frequency bands 150.05-153 MHz, 322-328.6 MHz, 406.1-410 MHz and 608-614 MHz from harmful interference from unwanted emissions as shown in the most recent version of Recommendation ITU R RA.769. (WRC 19)

  • 5.208B   In the frequency bands:

    137-138 MHz,
    157.1875-157.3375 MHz,
    161.7875-161.9375 MHz,
    387-390 MHz,
    400.15-401 MHz,
    1 452-1 492 MHz,
    1 525-1 610 MHz,
    1 613.8-1 626.5 MHz,
    2 655-2 690 MHz,
    21.4-22 GHz,

    Resolution 739 (Rev.WRC-19) applies. (WRC 19)

  • 5.209   The use of the bands 137-138 MHz, 148-150.05 MHz, 399.9-400.05 MHz, 400.15-401 MHz, 454 456 MHz and 459-460 MHz by the mobile-satellite service is limited to non geostationary-satellite systems. (WRC 97)

  • 5.262   Additional allocation: in Saudi Arabia, Armenia, Azerbaijan, Bahrain, Belarus, Botswana, Colombia, Cuba, Egypt, the United Arab Emirates, Ecuador, the Russian Federation, Georgia, Hungary, Iran (Islamic Republic of), Iraq, Israel, Jordan, Kazakhstan, Kuwait, Liberia, Malaysia, Moldova, Oman, Uzbekistan, Pakistan, the Philippines, Qatar, the Syrian Arab Republic, Kyrgyzstan, Singapore, Somalia, Tajikistan, Chad, Turkmenistan and Ukraine, the band 400.05-401 MHz is also allocated to the fixed and mobile services on a primary basis. (WRC 12)

  • 5.263   The band 400.15-401 MHz is also allocated to the space research service in the space-to-space direction for communications with manned space vehicles. In this application, the space research service will not be regarded as a safety service.

  • 5.264   The use of the band 400.15-401 MHz by the mobile-satellite service is subject to coordination under No. 9.11A. The power flux-density limit indicated in Annex 1 of Appendix 5 shall apply until such time as a competent world radiocommunication conference revises it.

  • US70   The meteorological aids service allocation in the band 400.15-406.0 MHz does not preclude the operation therein of associated ground transmitters.

  • US319   In the bands 137-138 MHz, 148-149.9 MHz, 149.9-150.05 MHz, 399.9-400.05 MHz, 400.15-401 MHz, 1610-1626.5 MHz, and 2483.5-2500 MHz, Federal stations in the mobile-satellite service shall be limited to earth stations operating with non-Federal space stations.

  • US320   The use of the bands 137-138 MHz, 148-150.05 MHz, 399.9-400.05 MHz, and 400.15-401 MHz by the mobile-satellite service is limited to non-voice, non-geostationary satellite systems and may include satellite links between land earth stations at fixed locations.

  • US324   In the band 400.15-401 MHz, Federal and non-Federal satellite systems shall be subject to electromagnetic compatibility analysis and coordination.

Wiki entries

Radiosondes

Current Use
400.15–406 MHz Radiosondes
According to the U.S. National Weather Service:

In order to understand the dynamic processes that result in the weather we experience, we need to know what is happening through the entire atmosphere. These observations are primarily taken with the aid of radiosondes.

The radiosonde is a small instrument package that is suspended below balloon filled with either hydrogen or helium. As the radiosonde is carried aloft, it measures pressure, temperature, and relative humidity.

These sensors are linked to a battery-powered radio transmitter that sends the information to a ground receiver. By tracking the position of the radiosonde in flight via GPS (Global Positioning System), measurements of wind speed and direction aloft is also obtained.

Worldwide, most radiosonde observations are taken daily at 00Z and 12Z (6 a.m. and 6 p.m. EST). With worldwide coordination of these upper air observations, we can obtain a picture of the various pressure and wind patterns across the globe.

Radiosonde observations technically provide only pressure, temperature, and relative humidity data; the tracked position of a radiosonde is actually called a rawinsonde observation and is used to obtain wind speed and direction. However, meteorologists and other data users frequently refer to them as part of the radiosonde observation.

The radiosonde flight can last in excess of two hours, and during this time the radiosonde can ascend to over 115,000 feet (35,000 m) and drift more than 125 miles (200 km) from the release point. During the flight, the radiosonde is exposed to temperatures as cold as -130°F (-92°C) and air pressures of only a few hundredths of what is found on the Earth's surface.

When the balloon has expanded beyond its elastic limit (20-25 feet in diameter) and bursts, the radiosonde returns to Earth via a small parachute. This slows its descent, minimizing the danger to life and property.

If found, radiosondes are safe to handle, as long as the balloon is deflated. Cut the string to the balloon/parachute and place them in a trash receptacle. You may also dispose of the radiosonde itself or keep it.

Worldwide, there are about 1,300 upper-air stations. Observations are made by the NWS at 92 stations: 69 in the conterminous United States, 13 in Alaska, nine in the Pacific, and one in Puerto Rico.

NWS supports the operation of 10 other stations in the Caribbean. Through international agreements, data are exchanged between countries worldwide.