The Committee on Radio Astronomy Frequencies (CRAF) is a committee of
the European Science Foundation (ESF).
403 - 406 MHz: METEOROLOGICAL AIDS Fixed Mobile except aeronautical mobile 406 - 406.1 MHz: MOBILE-SATELLITE (Earth-to-space) 5.266 5.267 406.1 - 410 MHz: FIXED MOBILE except aeronautical mobile RADIO ASTRONOMY 5.149 410 - 420 MHz: FIXED MOBILE except aeronautical mobile Space Research (space-to-space) 5.268
National Arrangements for Radio Astronomy different from ITU-R Radio Regulations:
Astrophysical importance of the band 406.1 - 410 MHz
|System Sensitivity (noise fluctuations)||Threshold Interference Levels|
|Temperature||Power Spectral Density||Input Power||Power Flux Density||Spectral Power Flux Density|
|Single Dish||0.96 mK||-259 dB(WHz-1)||-203 dBW||-189 dB(Wm-2)||-255 dB(Wm-2Hz-1)|
For further details the reader is referred to ITU-R Recommendation RA769. It should, however, be noted that the observed spectral power flux densities are much lower than the harmful interference levels because they are made in the main beam of the radio astronomy antennas whereas the harmful levels correspond to reception in the sidelobes, i.e. the differences are related to the gain of the antennas. The differences can be of the order of 50 to 80 dB W m-2 Hz-1 (see ITU-R "Handbook on Radio Astronomy", 1995/2003, chapter 4).
In Europe, the band 406.1 - 410 MHz is used by the Radio Astronomy Service in:
Sharing problems with the following services:
Out-of-band emission from the following services:
Spurious emission from the following services: