Committee on Radio Astronomy Frequencies

The Committee on Radio Astronomy Frequencies (CRAF) is a committee of the European Science Foundation (ESF).

ESF Expert Committee on Radio Astronomy Frequencies (CRAF)

Progress Report for 2001

CRAF is the ESF Expert Committee on Radio Astronomy Frequencies. CRAF co-ordinates the efforts on frequency protection for European radio astronomy, passive remote sensing and related sciences.

The contours of the World Radio Conference WRC-2003 have largely determined CRAF’s activities in 2001. These contours are drawn in the WRC-03 agenda, which contains several items important for radio astronomy. The WRC-2003 will take place in June 2003 in Caracas, Venezuela. CRAF’s activities concentrated on studies towards the development of a common European position for this conference, in close and active cooperation with the Conférence Européenne des Postes et des Télécommunications (CEPT). The CEPT represents 43 Administrations and is responsible for European radio frequency management.

Among the WRC-03 items relevant for radio astronomy the following should be noted:

  • completion of the development of mandatory limits on unwanted emissions from transmitters on spacecraft. (Unwanted emissions are a form of radio pollution produced by the transmitter but not needed by the receiver).
  • regulation of High-Altitude Platform Systems (HAPs) applications (in particular its impact on frequency bands used by radio astronomy between 30 and 50 GHz).
  • Feeder links to/from space systems adjacent to the frequency band 1400-1427 MHz. This frequency band is the most important band for radio astronomy because it contains the emission from neutral hydrogen (HI) and degradation of radio astronomy observations in this band will have severe impact on further development of astronomy.

    CRAF also participates actively in various CEPT working groups and project teams on other important issues, such as the impact of telecommunication by cable systems and Ultra Wideband Transmission technology. The latter development has significant impact on the fundamentals of radio frequency regulation and management. In particular, regulations specific to protect the vulnerable passive radiocommunication services is currently under severe pressure by industrial interests.

    Having a single radio astronomy position on these issues is essential. CRAF provides input to the CEPT to ensure that radio astronomy and related scientific use of frequencies is known and properly protected. Since 2000, CRAF has a formal observer status within the CEPT. This enables CRAF to participate with European administrations at all levels within CEPT. The CEPT Electronics Communications Committee has also sent a representative to CRAF.

    The CRAF members of IUCAF, the Commission on the Frequency Allocations for Radio Astronomy and Space Sciences of UNESCO, also help to propagate and support the common European CEPT positions on issues related to the fields of science they represent on a worldwide level within the ITU, the International Telecommunication Union.

    The CRAF Newsletter which is available on the World Wide Web and in hardcopy format, continues to enjoy a wide interest among administrations, industry and research organisations.

    CRAF had two plenary meetings in 2001: in Gothenburg/Onsala (Sweden) on 19-20 April and in Bordeaux (France) on 22-23 October.

    Last modified: May 3, 2002