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World Radiocommunication Conferences (WRCs)

Tomas E. Gergely

Summer School on Spectrum

Management and Radio Astronomy

Green Bank, June 2002

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WRCs: Introduction

WRCs Are a Big Deal!

WRC-00 Attended by: 2037 delegates

from 150 countries

83 companies

326 observers

from 95 organizations

Over 500 Documents

For a Feel of a WRC (WRC-97), as Experienced by An Astronomer, see:

http://dsnra.jpl.nasa.gov/freq_man/wrc97.html

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n WRCs: History (1) 1865 First International Telegraph Convention signed in Paris by the 20 founding

members, and the International Telegraph Union (ITU) established

1906 First International Radiotelegraph Conference held in Berlin signs the first International Radiotelegraph Convention. The annex to this Convention contained the first regulations governing wireless telegraphy. Expanded and revised by numerous radio conferences, these are now known as the Radio Regulations

1927 Washington D.C. Conference held to establish the International Radio Consultative Committee (CCIR)

1932 Madrid Conference, decides to combine the International Telegraph Convention of 1865 and the International Radiotelegraph Convention of 1906 to form the International Telecommunication Convention, and to change the name of the Union to International Telecommunication Union.

1947 Atlantic City Conference held with the aim of developing and modernizing the organization. The ITU becomes a UN specialized agency. The International Frequency Registration Board (IFRB) is established to coordinate the increasingly complicated task of managing the radio-frequency spectrum. The Table of

Frequency Allocations, introduced in 1912, is declared mandatory. 1959 CCIR sets up a study group responsible for studying space

radiocommunication. 1963 Geneva, Extraordinary Administrative Conference for space communications

held to allocate frequencies to the various space services.

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nWRCs: History (2)

Before 1993 WRCs came in two flavors:Specialized and G-WARCs, and were held on an “as needed” basis

WRCs held between 1979 and 1992:

• 1979 G-WARC (WARC-79)• 1983 Mobile WARC (WARC Mob-83) • 1984 HFBC WARC (HFBC-84)• 1985 WARC on Geostationary

Orbit Use (ORB-85)• 1987 HFBC WRC (HFBC-87)• 1987 Mobile WARC (WARC Mob-87)• 1988 WARC on Geostationary

Orbit Use (ORB-85)• 1992 WARC for Dealing with

Allocations in Certain Parts

of the Spectrum (WARC-92)

Since 1993 WRCs Have Been Held Regularly, at 2-3 Year Intervals, With Unrestricted Agendas

WRCs held since 1993:• Geneva 1995 (WRC-95)

• Geneva 1997 (WRC-97)

• Istanbul 2000 (WRC-00)

• Caracas 2003 (WRC-03)

• ? 2006 (WRC-06)

New Regulations (in Particular, Frequency Allocations) Are Adopted at and by WRCs, and Are Incorporated Into the RR

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n Radio Astronomy at WRCs 1950 Zurich URSI GA Need to have frequency bands reserved for radio astronomy

discussed for the first time.

1959 WARC, Geneva, Ch. Seeger, RA Representative (4 months, at $15 per diem!):Radio

Astronomy recognized as a “service”

Protection provided to the HI line in the RR

Footnote protection provided to other bands

Further discussions and “studies” at Space WARC-63

IUCAF formed, to prepare RA positions for WARC-63

1963 Space WARC, Geneva:

IUCAF participates for the first time

OH line discovery announced, secondary allocations to main OH lines made

1971 WARC-ST, Geneva:

Allocations made up to 275 GHz

Table allocations to RA: OH (1665 & 1667 MHz), NH3 (23.7 GHz)

and HCN(86.3 and 88.6 GHz)

Footnote allocations to 7 other lines

Recommendation on the Shielded Area of the Moon Reserved for RA

1979 G-WARC, Geneva, 14 RA Representatives for various periods, 6 weeks

16 bands allocated in the Table to RA, up to 116 GHz

18 bands allocated by footnote above 140 GHz above 140 GHz

Recommendation 66 approved, first concerns about out-of-band emissions

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n Radio Astronomy at WRCs (2) 1987 Mob-WARC, Geneva, 1 RA Representative

Limited Impact on RA

1988 WARC-Orb, Geneva, 1 RA Representative

1992 WARC, Malaga-Torremolinos, 9 RA Representatives (6 IUCAF, 3 on Nat. Delegations):

Frequencies allocated to IRIDIUM, 1612 MHz allocation upgraded to primary, RR 733E approved

1993 WRC, Geneva, 2 RA Representatives, both IUCAF Conference to determine Agenda and timing of future conferences only

1995 WRC, Geneva, 9 RA Representatives (5 IUCAF, 4 on National Delegations Frequencies allocated to Teledesic (Broad-band systems), various

footnotes protecting RA approved Radio Regs “simplified”

1997 WRC, Geneva, 14 RA Representatives (7 IUCAF, 7 on National Delegations) Aggregate interference pfd’s make first appearance, FSS allocated to 40.5-

42.5 GHz Recommendation 66 is revised 15 GHz radio astronomy allocation is protected to specific pfd level Protection of RA at 42 GHz is addressed

2000 WRC, Istanbul, 17 RA representatives (3 IUCAF, 14 on National Delegations) 71- 275 GHz spectrum realigned to accommodate passive needs 3 RA bands protected to specific pfd levels from adjacent satellite

downlinks) 42 GHz RA allocations protected

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n The ITU Framework International Uses of the Radio Spectrum Are Regulated by the

International Telecommunication Union (ITU), an Organ of the United Nations, Through the Radio Regulations

The Radio Regulations Constitute an International Treaty on All Aspects of Radiocommunications, Covering the Use of the Radio-Frequency Spectrum by Radiocommunication Services (ITU Webpage)

The International Table of Allocations Is Part of the Radio Regulations (Article 5). Within the Current Practices of the ITU, Radiocommunication Is Considered to Encompass the Spectrum Below 3 000 GHz, but at Present, Spectrum Allocations Cover Only up to 275 GHz

This is Likely to Change: Proposal to the Plenipot Conference (Sept. 2002) to Extend ITU Mandate to

Optical Wavelengths, Essentially Without Limits WRC-06 Is Likely to Tackle Allocations up to 1 000 GHz

Countries Are Sovereign With Regard to the Use of the Radio Spectrum (And Regulation) Within National Borders and Have No Obligation to Adopt or Follow the International Table of Allocations

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n How Do WRCs Impact Radio Astronomy?

Directly Through: Allocations:

In-Band Sharing Adjacent Band Allocations (Satellite Downlinks) Footnotes Establishing (or not establishing) Standards (e.g.

Spurious Emissions, Frequency Tolerances, etc.) Other Regulations (e.g. Coordination Zones)

Mandating Studies That May Affect The Status Of Radio Astronomy In Various Regions Of The Spectrum

Other Regulations (e.g. Coordination Zones around Radio Observatories, Earth Stations, etc. )

Placing Radio Astronomy Issues (or Related Issues) On The Agenda of Future WRCs

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n How Do WRCs Work: Agendas and Proposals

The scope of each WRC is limited by its Agenda Each WRC develops and formally adopts a draft Agenda

(contained in a Resolution) for the next conference, and a provisional

agenda for the one after. Currently Agendas have many unrelated items, e.g: A.I. 1.15 (WRC-03)

to review the results of studies concerning the radionavigation-satellite service in accordance with Resolutions 604(WRC-2000), 605(WRC-2000), and 606 (WRC-2000);

The draft Agenda for each WRC must be formally approved by the ITU Administrative Council, which meets annually. Once approved, the Agenda is submitted to Member States for final adoption and often there is considerable fight over Agenda Items

WRCs work by considering Proposals that may be submitted only by Member Administrations of the ITU in good standing

The deadline to submit proposals is set (usually) some six months prior to the beginning of the WRC (and is routinely ignored)

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nProposals: An Example

WRC-2000 Agenda Item 1.14

To review the results of the studies on the feasibility of implementing non-GSO MSS feeder links in the 15.43-15.63 GHz in accordance with Resolution 123 (WRC-97).

Remove the 15.43-15.63 GHz space-to-Earth allocation from the Tables of Article RR S5

Background Information: Studies conducted subject to Resolution 123 (WRC-97) dealt with two aspects 1. Need for the allocation to non-GSO MSS feeder links in the band 15.43-15.63 GHz (space-to-Earth); 2. feasibility of implementing non-GSO MSS feeder links in the band 15.43-15.63 GHz (space-to-Earth) regarding protection of RAS, EESS (passive) and SRS (passive) operating in the band 15.35-15.4 GHz. The ITU-R studies concluded that the space-to-Earth operation of non-GSO MSS feeder links in parts of the 15.43-15.63 band is significantly difficult and sometimes impossible, due to technical limitations that would have to be imposed on the feeder links. The ITU-R studies complied with the Res. 123 (WRC-97) provisions completely and hence covered all issues related to Agenda item 1.14. Taking into account that Res. 123 (WRC-97) has attained its objectives and aims, it would be appropriate to suppress it. The results of the studies, as reported in the CPM report, showed that it should be feasible to implement the existing non-GSO MSS feeder downlinks in the band 15.43-15.63 GHz taking into account the protection requirements for RAS and other passive services in this band. Providing that the existing non-GSO MSS feeder downlinks systems planning to use this band can provide the required protection to the passive services, the ITU-R studies did not identify any additional technical or operational disadvantages with respect to the existing systems. The CPM report also concludes that, for future non-GSO MSS systems using the space-to-Earth allocation at 15.43-15.63 GHz substantial mitigation techniques would be required to adequately protect the RAS from harmful interference. The technical studies also concluded that, because of high levels of suppression of out-of-band emissions required, use of the band 15.43-15.63 GHz for space-to-Earth feeder links should not extend beyond non-GSO MSS satellite networks for which advanced publication information has been received by the Bureau prior to WRC-2000. Common CITEL proposals were developed to reflect this point of views.

GHz Allocation to services

Region 1 Region 2 Region 3 15.43 – 15. 63

FIXED SATELLITE (space-to-Earth) (Earth-to-space) MOD S5.511A AERONAUTICAL RADIONAVIGATION S5.511C

Suppress Resolution 123

RESOLUTION 123 (WRC-97)

Feasibility of implementing feeder links of non-geostationary satellite networks in the mobile-satellite service in the band 15.43 – 15.63 GHZ (space-

to-earth) while taking into account the protection of the radio astronomy service, the earth exploration-satellite (passive) service and the space research

(passive) service in the band 15.35 – 15.4 GHZ Modify S5.511A as follows: S5.511A Use of the band 15.43-15.63 GHz by the fixed satellite service (space-to-Earth (see Resolution 123 (WRC-97)) and Earth-to-space) is limited to feeder links of non-geostationary systems in the mobile-satellite service, subject to coordination under No. S911A. In the space-to-Earth direction, the use of this band is limited to feeder links of non-GSO MSS systems for which advanced publication information has been received prior to WRC-2000 the minimum earth station elevation angle above and gain towards the local horizontal plane and the minimum coordination distances to protect an earth station from harmful interference shall be in accordance with Recommendation ITU-R S.1341. Also in the space-to-Earth direction, harmful interference shall not be caused to stations of the radio astronomy service using the band 15.35-15.4 GHz. The threshold levels of interference and associated power flux-density limits, which are detrimental to the radio astronomy service, are given in Recommendation ITU-R RA.769-1 for 98% of the time. Special measures will need to be employed to protect the radio astronomy service in the band 15.35-15.4 GHz. (WRC-97)

IAP/14/51

SUP

IAP/14/52

MOD

IAP/14/50

MOD

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nHow Do WRCs Work: STRUCTURE 1

PLENARY

(Chairman)

GT (WG) of PLENFuture AgendasTechnical Studies

Com 1Steering

Com 2 Credentials

Com 3 Budget

Com 6Editorial

COM 4

ALLOCATIONS

COM 5 REGULATORY

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n How Do WRCs Work: STRUCTURE 2

5A1 5A2SAT . COORD

PROCEDURES

5A3APP S7

COORD AREASA I 1.3

COM 5A

5B1FOOTNOTEDELET IONS

A I 1 .1

5B2APP S3

SPURIOUSEM ISSIONS A I 1 .2

5B3 5B4INCORP by

REFERENCEA I 2

5B5CONT

OF RES/RECSA I 4

COM 5B

COM 5REGULATORY

MATTERS

COM 5A1IM T-2000

A I 1 .6

5A1DG11.4 G Hz

5A1DG2406 M Hz

M SS < 1 GHzA I 1 .11

GENERICM SS/AM SS

A I 1 .10

C O M 4A

GPS/M SSA I 1 .9

RNSS at 5 G HzA I 1 .15.1

RNSSs-s

A I 1 .15.2

COM 4B

HDFS(42 G Hz)

A I 1 .4

ABOVE 71 GHzA I 1 .16

HAPSA I 1 .5

EESS18.6-18.8 G Hz

A I 1 .17

COM 4C

NG SO FSS10.7 G HzA I 1 .13

FEEDER LINKS20/30 GHz

15 GHzDOW NLINKS

A I 1 .14

C O M 4D

COM 4ALLOCATION

M ATTERS

Main CommitteesEssential To Radio Astronomy

Interest To Radio Astronomy

No Radio Astronomy Interest

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n How Do WRCs Work: Mechanics

Proposals Are Attributed to the Various Subcommittees and Introduced in Detail

Subcommittees or Drafting Groups Are Formed Until a Manageable Size is Reached (Often Nested 5-6 Levels Deep)

Consensus is Sought in the Subgroups, Many Meetings May Be Necessary to Resolve an Issue

If Consensus Is Reached, The Consensus Proposal Is Elevated to the Parent Group for Approval (and so on, until it reaches the Plenary)

If Consensus Is Impossible to Reach, Chairman of Parent Group IS Informed

Votes Are Taken Only as a Last Recourse, When All Attempts atReaching Consensus Failed

Often There Is only a Partial Resolution of an Issue, With Resolutions for Further Studies, and the Issue Revisited at the Next WRC

Much (but not all!) Depends on the Chairpersons’ ability to conduct the Meetings and Force Consensus

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n How Do WRCs Work:Mechanics

Compromise is sought to the maximum extent possible, votes are avoided as much as possible

One country, one vote rule favors the formation of (regional) blocs Delegations, representing members (e.g. IUCAF), work by trying to

influence Administrations by: • Lobbying• Information Papers • Addressing the Floor, if Allowed to Do So • Any other way possible, (some legal, some less so)

Radio Astronomers participate through:• National Delegations (participate in developing national

positions, delegation meetings, as spokespersons, etc., they are however, bound by national positions )

• IUCAF (free to lobby, not bound by [but usually also unable to influence] national positions)

• Both necessary, some countries allow participation in both, others don’t

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nConsensus Reached : Mm-wave

Allocations (WRC-00)REASONS FOR SUCCESS:

Systems Above 71 GHz Are Under Development, But Are Not Yet Operational, So No Costly Assets Needed to Be Relocated

Astronomers coordinated proposals very closely and carefully during the process leading up to the WRC. This resulted in nearly identical proposals by the three large regional groups within the ITU (CITEL, CEPT and APT)

Astronomy Proposals Were Also Carefully Coordinated With Remote Sensing Community (and Amateurs)

Flexibility Shown By Astronomy Community In Developing Proposals

Active Services Distracted By Many Other WRC Related Concerns

Few Active Commercial Requirements in This Spectral Region Yet (But Situation Changing Rapidly, e.g. FCC Push to Commercialize 90- 94 GHz )

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n Consensus Not Reached:40 GHz Allocations

The Issue

Radio Astronomy Allocations at 42.5-43.5 GHz (7-mm continuum) and a) the 42.821 GHz, 43.122 GHz and 43.423 GHz SiO lines (listed in RR 5.149 and in Rec. ITU-R RA.314) and b) the 42.159 GHz SiO line (not listed in either of the above) need to be protected from Unwanted Emissions of Satellite Downlinks (FSS and BSS) intending to operate in the adjacent lower band.

VLA image of two protoplanetary disks in a molecular cloud in the constellation Taurus. The colors represent relative intensity, or brightness, of the radio emission coming from these disks; red is strong emission and blue is weak emission. The scale bar shows a distance of 20 Astronomical Units (AU). An Astronomical Unit is the distance between Earth and the Sun. In our own Solar System, the planet Uranus is about 19 AU from the Sun.

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n Consensus Not Reached:40 GHz Allocations

Situation until WRC-97: BSS Allocation in 40.5-42.5 GHz Band - Never Implemented

WRC-97: FSS Downlink Allocation made in 40.5-42.5 GHz band, in spite of Radio Astronomy opposition Allocation subject to conditions specified in Res. 128 (WRC-97) and Res. 129

(WRC-97)• Identify measures (technical and operational) to protect RA from harmful

interference from emissions in 41.5-42.5 GHz band. Identify measures to decrease susceptibility of RA stations (Res 128)

• Allocation (41.5-42.5 GHz) not to be implemented until above accomplished • Other sharing issues in the full 40.5-42.5 GHz band (Res. 129)

• Some “studies” performed by the radio astronomy community. Help requested from satellite industry, but no satellite studies performed.

• Pressures from many countries and Fixed Service interests to segment allocation into: 40.5-41.5 GHz portion for FSS

• 41.5- 42.5 GHz for Fixed Service

WRC-00: Allocation provisionally subject to S5.551G, pfd limit imposed in the 42.5-

43.5 GHz band, from all space stations operating in the 40.5-42.5 GHz band. Studies to go on under Res. 128, issue to be revisited at WRC-03 Possibility of deletion of BBS from 41-41.5 GHz also studied.

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n

WRC OutputThe output of a WRC is contained in the

“Final Acts”, a Treaty Document. (In the U.S. it has to be ratified by the U.S. Senate. This may take a lo…..ong time!

Administrations may except themselves from complying with some provisions of the Final Acts, through the mechanism of taking a “reservation”. These are appended to the Final acts.

In the U.S. Implementation of the FA of the WRC follows the two track process

NTIA, usually through an AH group of the IRAC FCC, through NPRMs

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n WRC Preparations: The International Process

Preparations for the (Next) WRC Start As Soon As One Ends. They Are Channeled Towards the Conference Preparatory Meeting (CPM), That Prepares a Report Containing the “Technical” Basis for the Various Agenda Items

First CPM Meeting, Held Immediately After the WRC, Determines the Content and Organization of the CPM Report, Based on the WRC Agenda

Studies, Mandated in WRC Resolutions Are Carried Out (or not!) in the Various Study Groups

“Responsible” SGs Draft CPM Text, With Input From Other “Interested” SGs

Draft CPM Report Is Put Together by Chapter Rapporteurs Second CPM Meeting Held, Usually 6 Months Before the

WRC, to Finalize CPM Report CPM Meetings Have Become Very Political and Often

Serve to Stake Out Preliminary Positions for the WRC, Rather Than Attempting to Solve Technical Issues

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n WRC-03 Agenda Items of Interest to Radio Astronomy (1)

AI 1.8 to consider issues related to unwanted emissions: 1.8.1 consideration of the results of studies regarding the boundary

between spurious and out-of-band emissions, with a view to including the boundary in Appendix S3;

1.8.2 consideration of the results of studies, and proposal of any regulatory measures regarding the protection of passive services from unwanted emissions, in particular from space service transmissions, in response to recommends 5 and 6 of Recommendation 66 (Rev.WRC-2000);

AI 1.11 to consider possible extension of the allocation to the mobile-satellite service (Earth-to-space) on a secondary basis in the band 14-14.5 GHz to permit operation of the aeronautical mobile-satellite service as stipulated in Resolution 216 (Rev.WRC-2000);

AI 1.13 to consider regulatory provisions and possible identification of existing frequency allocations for services which may be used by high altitude platform stations, taking into account No. S5.5RRR and the results of the ITU-R studies conducted in accordance with Resolutions 122 (Rev.WRC-2000) and 734 (WRC-2000); [31 GHz]

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nWRC-03 Agenda Items of

Interest to Radio Astronomy (2) AI 1.15 to review the results of studies concerning the

radionavigation-satellite service in accordance with Resolutions 604 (WRC-2000), 605 (WRC-2000) and 606 (WRC-2000); [5 GHz]

AI 1.16 to consider allocations on a worldwide basis for feeder links in bands around 1.4 GHz to the non-GSO MSS with service links operating below 1 GHz, taking into account the results of ITU-R studies conducted in response to Resolution 127 (Rev.WRC-2000), provided that due recognition is given to the passive services, taking into account No. S5.340; [1.4 GHz]

A. 1.32 to consider technical and regulatory provisions concerning the band 37.5-43.5 GHz, in accordance with Resolutions 128 (Rev.WRC-2000) and 8 (WRC-2000);

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nREFERENCES

Findlay, J.W. “IUCAF and Frequencies for Radio Astronomy”, in IAU Colloquium No. 112 (D. L.Crawford, ed.), Light Pollution, Radio Interference and Space Debris,

1991, Astr. Soc. Pacific Conf. Ser. , Vol. 17 Robinson, B. “Frequency Allocation: The First Forty Years”, Ann. Rev. Astron.

Astrophys., 1999, 37, 65

Kuiper, T. B. H. ,”WRC-97, Geneva, Nov. 2-7”, at: http://dsnra.jpl.nasa.gov/freq_man/wrc97.html

Websites of the International Telecommunication Union (ITU): http://www.itu.int/aboutitu/index.html http://www.itu.int/ITU-R/conferences/wrc/index.html