4. CRAF and IUCAF in the ITU
Since spring 1998, CRAF is sector member of the ITU Radiocommunication Sector. From
then on,
the radio astronomy community participates in ITU-R activities under the umbrella of IUCAF
(which was already ITU-R sector member) and of CRAF. Given the European scope of the
work of
CRAF, it is obvious that CRAF's prime attention in ITU-R Sector work concerns the radio
astronomy interests in Region 1 (in ITU-R terminology, Region 1 = Europe, Africa ...),
with emphasis on Europe. On the basis of its mandate, IUCAF deals with global issues.
Although from the scientific point of view the global nature of radio astronomy interests are
guided by the universal laws of physics, various reasons of political, economic, project
selection etc. lead to radio astronomy interests specific for Europe. CRAF especially
follows attentively the development of CEPT opinions and activities.
Given these consideration, CRAF sees its role in the ITU as a strengthening of the radio
astronomy contribution to the work of the ITU-R. Wherever possible, CRAF and IUCAF
have to work closely together, but in cases specific to Region 1, especially to Europe, CRAF's
contribution is a constructive European articulation of the radio astronomy contribution to
the ITU. An example of this is the preparation for the WRC2000 or CRAF input to ITU-R
Study Groups and Working Parties.
5. Preparations for WRC2000
ITU-R World Radiocommunication Conferences are held every two years. The last
conference was held in 1997, WRC97. The next conference will be held in 2000, WRC2000.
The importance of this conference for radio astronomy is that the agenda contains a large
number of issues of great to significant importance to radio astronomy. The agenda items
which have most impact on radio astronomy are (in ITU-R/WRC jargon):
- 1.2 - finalize the remaining issues on spurious emission in Appendix S3 for space
services;
- 1.4 - consider issues relating to allocations and regulatory aspects related to Resolutions
126 (31.8 - 33.4 GHz high density fixed service),
127 (40.5 - 42.5 GHz FSS (space-to-Earth)) and others;
- 1.5 - consider regulatory provisions and possible additional frequency allocations for
services using HAPs taking into account the results of Resolution COM5-7;
- 1.6.1 - review the spectrum requirements for the operation of terrestrial IMT-2000 with
the view to identify future expansion bands and adjustments to the Table of Allocations;
- 1.9 - take into account the results of ITU-R studies in evaluating the feasibility of an
allocation in the space-to-Earth direction to the MSS in a portion of the 1559 - 1567 MHz
frequency range, in response to Resolutions 213 and COM5-31;
- 1.10 - to consider the results of ITU-R studies in accordance with Resolution COM5-24
(Use of the bands 1525 - 1559 MHz and 1626.5 - 1660.5 MHz by the MSS);
- 1.11 - consider constraints on existing allocations and to consider additional allocations
on
a worldwide basis for the non-GSO/MSS below 1 GHz, taking into account Resolutions 214
(Rev WRC-97) and COM5-25 (406 MHz);
- 1.13 - on the basis of the results of the studies in accordance with Resolution COM5-18
on
the "Use of NGSO systems in the FSS in certain frequency bands"
- 1.14 - review the results of the studies on the feasibility of implementing non-GSO MSS
feeder links in the 15.43 - 15.63 GHz range in accordance with Resolution COM5-8;
- 1.15.1 - to consider new allocations to the Radionavigation-Satellite Service required to
support developments in the range from 1 to 6 GHz;
- 1.16 - to consider allocation of frequency bands above 71 GHz to the EES (passive) and
RAS,
taking into account Resolution COM5-1;
- 1.17 - to consider possible worldwide allocations for the EES (passive) and SR (passive)
services in the band 18.6 - 18.8 GHz taking into account the results of the ITU-R studies.
CRAF participates actively in CEPT project teams which work towards preparation for
WRC2000. On
some issues some remarks can already be made:
On agenda item 1.4, CRAF expressed the radio astronomy concerns on unwanted emissions
spilling
over from transmissions from space-to-Earth transmissions
in the frequency bands just below 42.5 GHz into the band 42.5-43.5
GHz in
which radio astronomy has a primary allocation. CRAF considers it technologically
impossible to
protect radio astronomy observations from unwanted emissions from space-to-Earth
transmissions
in a frequency band adjacent to a frequency band allocated to radio astronomy at these high
frequencies. This radio astronomy position endorses the concerns on the protection of radio
astronomy expressed during WRC97. This agenda item also addresses the opening of the
band 31.8-33.4
GHz for high density fixed service applications (Resolution 126(WRC97)). These
transmissions
should take place in the uplink direction. CRAF participates in various studies to ensure that
adequate coordination is ensured.
On the issue of allocation of frequencies above 71 GHz (agenda item 1.16), CRAF
contributed to
the CEPT project team working on this. The cooperation with the remote sensing community
for
which these frequencies are also of great interest helped the project team very much to be able
to develop a draft table which is currently subject to refinement. The CRAF position was
intensively coordinated with IUCAF and ITU-R WP7D (as indicated in the report of WP7D).
In parallel with the activities in IUCAF and radio astronomy communities
elsewhere, CRAF works actively on a radio astronomy position for Region 1.'
6. 1.4 GHz developments
The band 1400-1427 MHz was the first passive band allocated to the radio astronomy service
and it is still arguably the single most important band we have. The band contains the
1420-MHz transition of hydrogen, the most abundant element in the universe.
Resolution 127 (WRC-97) calls for studies of the bands 1390-1400 MHz and 1427-1432
MHz for possible use as feeder uplinks and downlinks for non-GSO MSS systems with
service links operating below 1 GHz. But for Hurricane Georges those studies might have
been concluded by now.
At its meeting in Geneva in September 1998, ITU-R Working Party 7D (radio astronomy)
received a liaison statement from WP8D (MSS), dated 13 May 1998, and allegedly issued in
response to a request from WP7D for technical information on the proposed feeder links near
1.4 GHz. The liaison statement contained results of a technical study purporting to show
that the band 1427-1432 MHz would be suitable for the feeder downlink! This study was
carried out in the USA on behalf of a satellite company. The details were sent from WP8D to
WP7D for comment. The same information was also sent from WP8D to WP7C for
comment, as the earth exploration satellite service (passive) also has an allocation in the band
1400-1427 MHz.
WP7C received this liason statement and also a delayed contribution from the USA dealing
with the very same issue. The delayed contribution was in fact a further instalment of the
ongoing compatibility study being carried out in the USA. The delayed contribution was
framed as an answer to the liaison statement from WP8D. WP7C assigned both documents to
a one-man drafting group, who happened to be the author of the USA technical study, who by
a strange coincidence was making his debut in ITU circles in Geneva. The drafting group
reported favourably on the sharing study and the delayed USA contribution was accepted by
WP7C with minor editorials. How convenient to have the answer to the question already
prepared by the man who wrote it. All the busy delegates had to do was to rubber stamp the
ready-made answer.
WP7D was to have received a parallel contribution from the USA, by the same author, but
unfortunately while the document was being considered at Arecibo, Hurricane Georges
struck. Because of this accident, the document reached Geneva too late to be formally
considered, but it was kindly made available to WP7D to help them deal with the liason
statement from WP8D. Without the services of the WP7C drafting group WP7D was unable
to complete the symmetric operation of sending back an acceptance of the compatibility
study. Instead WP7D has sent back a liaison statement to WP8D indicating that there was not
time to review the compatibility study and that comments might be expected after the next
meeting of WP7D in March 1998.
7. Abbreviations used in this Newsletter
CEPT = Conference of European Post and Telecommunication administrations
CRAF = Committee on Radio Astronomy Frequencies (ESF)
EES = Earth Exploration Service(ITU-R)
ERC = European Radiocommunication Committee (CEPT)
ESF = European Science Foundation
FM = ERC Working Group Frequency Management (CEPT)
ITU = International Telecommunication Union
ITU-R = ITU Radiocommunication Sector
IUCAF = Scientific Committee on the Allocation of Frequencies for Radio Astronomy and
Space Science
MRC = Milestone Review Committee (ERC)
MSS = Mobile-Satellite Service
NRAO = National Radio Astronomy Observatory (US)
PNDR = Preliminary Draft New Recommendation (ITU-R)
RAS = Radio Astronomy Service (ITU-R)
RDSS = Radio Determination-Satellite Service
SE = ERC Working Group on Spectrum Engineering (CEPT)
SR = Space Research (ITU-R)
WARC = World Administrative Radio Conference (ITU)
WP = Working Party (ITU-R)
WRC = World Radiocommunication Conference (ITU-R)
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Last modified: February 8, 1999
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