ITU-R RA.1031-3 PDF

This Recommendation gives a practicable guideline for the case when one or more administrations, during negotiation, establish coordination zones around radio astronomy stations to protect the radio astronomy service from interference caused by terrestrial radiocommunication services or transmitting earth stations used for space radiocommunication services that share frequency bands with the radio astronomy service.

The ITU Radiocommunication Assembly,

considering

a) that the radio astronomy service is based on the reception of natural emissions at much lower power levels than are generally used in other radio services, and that the radio astronomy service is therefore particularly vulnerable to interference from transmitters in shared frequency bands;

b) that many frequency bands allocated to the radio astronomy service are also allocated to other services which transmit in those bands;

c) that protection from interference is essential to the advancement of the radio astronomy service, and that the preferred frequency bands for radio astronomy are given in Recommendation ITU-R RA.314;

d) that threshold levels of interference detrimental to the radio astronomy service and levels of data loss criteria are given in the relevant RA Series of ITU-R Recommendations;

e) that the detailed characteristics of the interference and the particular type of radio astronomical measurement may need to be taken into account when developing sharing criteria;

f) that radio astronomy sites are carefully chosen, and that site characteristics may strongly affect the sharing calculations;

g) that frequency sharing is generally impossible for transmitters within direct line-of-sight of a radio astronomy antenna,

recommends

1 that, in making assignments to services which share frequency bands with the radio astronomy service, administrations should take all practicable steps to avoid interference detrimental to the radio astronomy service;

2 that consideration be given to protecting radio astronomy sites from interference from transmitters used for terrestrial radiocommunications or from transmitting earth stations used for space radiocommunications in bands shared with the radio astronomy service with equal rights through the establishment of coordination zones around radio astronomy sites;

3 that the coordination zone may be calculated, taking account of the methodology contained in Annex 1.