1. Radio-Frequency Matters
Philippe TRISTANT
Frequency Manager of Météo France
Chairman of the Steering Group on Radio Frequency Coordination (SG-RFC)
WMO CBS-ISS
21 September 2006

2. Radio Frequencies
Radio-Frequency represent scarce and key resources for the meteorological community
stressed in WMO Resolution 3 SG-RFC(Cg‑XIV) – Radio frequencies for meteorological and related environmental activities –
radiocommunications are moving fast and there is a huge and increasing pressure on the whole spectrum from the industry representing huge economical an political interests
This could potentially put at risk the whole meteorological process
Justifying a global and increased involvement of the meteorological community in frequency matters to safeguard interests
WMO CBS-ISS
21 September 2006

3. SG-RFC Last SG-RFC was held 16-17 March 2006
Meeting Report is available at :
On short, the meeting :
Made a general review of all issues related to radio-frequency, recognising the increasing pressure on corresponding frequency bands
Supported the WMO implication in the GEO task on frequency (AR-06-11)
Noted the new issue on potential impact of wind-farms on radars
Adopted the preliminary WMO positions on World Radiocommunication Conference 2007 (WRC-07) agenda
WMO CBS-ISS
21 September 2006

4. Workshop
Following last SG-RFC, WMO organised a Workshop March 2006
The aim of this Workshop was to present the frequency issues to a larger number of WMO members as well as some outside organisations (ITU and European Commission in particular)
General and detailed presentations were ensured, in particular on presenting the WMO position related to WRC-07 :
Workshop was highly appreciated from both members and outside organisations
It was recognised that for next Workshop, enlarging outside invitation could help advertising both our frequency uses and requirements
WMO CBS-ISS
21 September 2006

5. SG-RFC and Workshop Message
WMO is able to raise positions and concerns to international bodies in charge of Frequency management
Our action is sometimes limited by the fact that Frequency issues are handled by National Radio Authorities (NRA)
NRA are in general not aware of the specific use of radio-spectrum by meteorological community and in particular obligations under the WWW
Each National Meteorological service needs to get involved by :
Contacting its NRA to relay our positions and concerns
providing SG-RFC all relevant information pertaining to their national situation
WMO CBS-ISS
21 September 2006

6. WRC-07 WRC-07 is schedule 22 October – 16 November in Geneva
The Conference Preparatory Meeting (CPM) will meet in Geneva 5-16 March 2007
7 items concern frequency bands or issues of prime interest for Meteorology
5 items do not directly concern meteorological interests but might have an impact on frequency bands used for meteorological purposes
WMO CBS-ISS
21 September 2006

7. WRC-07 agenda items of prime interest
agenda item 1.2 : Extension of the 18 GHz METSAT allocation and protection of the 10.7 and 36 GHz EESS (passive) bands
agenda item 1.3 : Upgrading and protection of radiolocation in the 9 GHz range, and 200 MHz extension of the Earth exploration satellite service (EESS) allocation at MHz
agenda item 1.4 : Impact on meteorological radars related to future frequency bands for IMT-2000
agenda item 1.12 : Coordination and notification procedures for Earth Exploration Satellite Service (EESS) (active and passive) sensors
agenda item 1.17 : Protection of the 1.4 GHz EESS (passive) band
agenda item 1.20 : Unwanted emissions in EESS (passive) bands
agenda item 7.2 : WRC-10 agenda (bands above 275 GHz)
WMO CBS-ISS
21 September 2006

8. Other WRC-07 agenda items of interest
agenda item 1.5 : Possible additional allocations for aeronautical telecommand and high bit-rate aeronautical telemetry between 3 and 30 GHz
agenda item 1.6 : Additional allocations for Aeronautical Mobile Service between 108 MHz and 6 GHz
agenda item 1.8 : High Altitude Platform Stations (HAPS) in the 28 and 31 GHz band
agenda item 1.18 : Pfd limits for Highly Elliptical Orbit (HIO) satellites in the frequency band GHz
agenda item 1.19 : Internet satellite applications
WMO CBS-ISS
21 September 2006

9. Agenda item 1.2 (WRC-07)
“to consider allocations and regulatory issues related to the Earth exploration-satellite (passive) service, space research (passive) service and the meteorological satellite service in accordance with Resolutions 746 (WRC-03) and 742 (WRC-03)”
3 issues related to meteorological applications :
Issue 1 : protection of the passive band GHz
Issue 2 : extension of the GHz METSAT allocation
Issue 3 : protection of the passive band GHz
WMO CBS-ISS
21 September 2006

10. Agenda item 1.2 (WRC-07)
Issue 1 : protection of the passive band GHz
the band GHz is vital for the study of global water circulation since this band is able to monitor the rain, the snow, the ocean ice and the water vapour for ocean and land surfaces
A number of passive sensors and radio altimeters are already using or are planning to use this frequency band in the near future
This band is shared with active services (Fixed and Mobile) that may interfere passive measurements if transmitting at high power
WMO supports the protection of the GHz passive bands and believes that identification of the maximum e.i.r.p and power for fixed and mobile links could provide a means to ensure such a protection.
WMO CBS-ISS
21 September 2006

11. Agenda item 1.2 (WRC-07)
Issue 2 : extension of the GHz METSAT allocation at 18 GHz
current allocation is given in RR footnote ( GHz)
Not sufficient to fulfil the expected requirements of next generation geostationary METSAT ( ) :
UV and IR sounding
Higher resolution and repetition rate
2 options for the extension:
GHz : political issues in relation with the appendix 30A BSS plan
GHz : few countries intend to use this band for high density FSS
WMO is of the view that such extension will not constrain existing services provided that the same regulatory conditions as in the GHz band (e.g. Article 21 pfd limits) are applied. WMO does not favour one of the options over the other ( GHz band or GHz band) but believes that a worldwide allocation in a single band would be preferred.
WMO CBS-ISS
21 September 2006

12. Agenda item 1.2 (WRC-07)
Issue 3 : protection of the passive band GHz
the band GHz is of primary interest to measure rain, snow, sea state and ocean wind for ocean and land surfaces
A number of passive sensors and radio altimeters are already using or are planning to use this frequency band in the near future
The band GHz is covered by RR footnote (all emissions are prohibited)
The band GHz is shared with active services (Fixed and Mobile) with limits set in footnote (40 dBW eirp and –3 dBW power)
WMO supports the protection of the GHz passive bands (the band GHz is covered under RR footnote 5.340). It should, however, be stressed that current deployments of FS links in certain administrations already create significant levels of passive measurement degradation in this band. Additional constraints on the GHz passive band would hence not be acceptable and therefore, WMO strongly encourages the identification of the maximum power and eirp for fixed and mobile services that would protect EESS (passive) in the GHz band.
WMO CBS-ISS
21 September 2006

13. Agenda item 1.2 (WRC-07)
RFI in unprotected band at 10.6 GHz over Europe and Japan.
From: Chris Kidd (Univ. Birmingham, UK)
WMO CBS-ISS
21 September 2006

14. Agenda item 1.3 (WRC-07)
“in accordance with Resolution 747 (WRC-03), consider upgrading the radiolocation service to primary allocation status in the bands 9 000-9 200 MHz and 9 300-9 500 MHz and extending by up to 200MHz the existing primary allocations to the Earth exploration-satellite service (active) and the space research service (active) in the band 9 500-9 800 MHz without placing undue constraint on the services to which the bands are allocated”
Meteorological radars in the MHz are currently seen as the adequate solution to improve the coverage of the radar networks deployed in the 2.8 and 5.6 GHz bands
2 issues related to meteorological applications :
Issue 1 : upgrading the radiolocation status in the MHz band
Issue 2 : Sharing between meteorological radars and EESS (active) in the MHz band
WMO CBS-ISS
21 September 2006

15. Agenda item 1.3 (WRC-07)
Issue 1 : upgrading the radiolocation status in the MHz band
the radiolocation service is currently secondary (no interference – no protection)
RR footnote states that “In the band MHz, ground-based radars used for meteorological purposes have priority over other radiolocation devices”
Current meteorological radars have been deployed without adverse impact on Radionavigation service
General support in ITU-R to allow for upgrading to primary but some countries wish to add a “no interference – no protection” footnote (de facto secondary)
WMO supports the upgrade to primary of Radiolocation Service in the band 9 300-9 500 MHz on an equal footing with Radionavigation Service retaining (either in the current or new footnote) the provisions of RR that addresses meteorological radars.
WMO CBS-ISS
21 September 2006

16. Agenda item 1.3 (WRC-07)
Issue 2 : sharing with EESS (active) in the MHz band
EESS (active) currently allocated in the MHz band
Need expressed for a 200 MHz extension to cover Synthetic Aperture Radars (SAR)
Current studies show that SAR may interfere with meteorological radars, but on a very short term
There is a wide consensus in the ITU-R in line with WMO position
Subject to final studies showing that the potential interference impact to meteorological radar operations is insignificant, WMO could support extension to the band 9 300-9 500 MHz of the EESS (active) and the space research service (active) allocations. The present RR footnote 5.476A would also need to be extended to this band. Also, WMO is of the view that, to limit the risk of interference, such extension should be limited to EESS (active) systems that needs a bandwidth higher than the current 300 MHz allocation. Should EESS (active) and space research service (active) allocations not be possible in the lower band, WMO could also support such allocations in the MHz band.
WMO CBS-ISS
21 September 2006

17. Agenda item 1.4 (WRC-07)
““to consider frequency-related matters for the future development of IMT‑2000 and systems beyond IMT‑2000 taking into account the results of ITU‑R studies in accordance with Resolution 228 (Rev. WRC-03)”
2 bands of interest for the meteorological community are currently considered for IMT-2000 identification :
MHz band : meteorological radars
MHz : EESS (active) in the MHz and MHz bands and meteorological radars in the MHz band
The case of the band MHz for satellite communications also needs to be stressed
WMO CBS-ISS
21 September 2006

18. Agenda item 1.4 (WRC-07)
The issue of the MHz band was already considered in preparation of WRC-2000
Despite studies showed that sharing is not feasible, a number of administrations are putting pressure on this band and propose to limit IMT to some kind of applications presenting less constraints !
The 5 GHz band was considered by the WRC-03 that allocated the band to the Mobile service, limited to RLAN, with a number of specific constraints to protect radars and EESS (active)
IMT-2000 (nomadic) may be identified under the RLAN constraints
In the too cases, there is also a high risk that once identified for IMT-2000, future initiative be made to relax or withdraw current limitations (see agenda item 1.9)
Keeping in mind studies in the MHz prior to WRC-2000 that already concluded on the non compatibility between IMT-2000 and radars, WMO is strongly opposed to any IMT-2000 identification in the MHz and MHz bands.
WMO CBS-ISS
21 September 2006

19. Agenda item 1.4 (WRC-07) Interference to 5 GHz radars from RLAN Poland
Hungary
WMO CBS-ISS
21 September 2006

20. Agenda item 1.20 (WRC-07)
“to consider the results of studies, and proposals for regulatory measures, if appropriate, regarding the protection of the Earth exploration-satellite service (passive) from unwanted emissions of active services in accordance with Resolution 738 (WRC-03)”
Highly sensitive and political issue, on the agenda of the last 3 WRCs
Concerns the main passive bands covered in RR footnote (All emissions are prohibited)
Technical work to determine the adequate out-of-band levels
Regulatory issue on whether or not to include these levels in the RR
WMO supports appropriate regulatory measures in the Radio Regulations to ensure the protection of the Earth exploration satellite service (passive) from unwanted emissions. Such measures should minimize the burden on the relevant active services but the protection of the related passive bands should be a prerequisite
WMO CBS-ISS
21 September 2006

21. Agenda item 7.2 (WRC-07)
Concern the preparation of the next WRC (2010/2011)
The Preliminary agenda for the 2010 World Radiocommunication Conference already includes the following item :
to consider frequency allocations between 275 GHz and 3 000 GHz taking into account the result of ITU-R studies in accordance with Resolution 950 (WRC‑03); The issue of the MHz band was already conisdered in preparation of WRC-2000
Passive sensing present direct interest for meteorological community (already few operational sensors)
Early assessment would be welcomed but there is a lack of knowledge concerning active services
WMO supports either the retention of agenda item 2.2 (WRC-10) or, as an alternative, consideration of a modified agenda item that would propose to review and revise RR footnote to update the uses of the spectrum from 275 to GHz by the Earth exploration-satellite (passive), radio astronomy, and space research (passive) services.
WMO CBS-ISS
21 September 2006

22. WMO output and actions for WRC-07
SG-RFC has issued Preliminary WMO positions that have been sent to ITU-R
WMO was represented (by SG-RFC members) and contributed within ITU-R groups
WMO secretariat will soon distribute these positions to all WMO members encouraging them to advertise to a large extent these positions, in particular to their NRA
A revised version of WMO positions will be prepared prior to the CPM to take advantage of recent ITU-R discussions
Also, the possibility to organise a Workshop during CPM (targeting on Radio Administrations) is under consideration
WMO representation and contributions will be ensured for WRC-07, but detailed organisation yet to be defined
WMO CBS-ISS
21 September 2006

23. Generic UWB applications
new technology for civil applications using bandwidth of several GHz and transmits at very low power (mainly below 10 GHz but also Automotive radars at 24 GHz)
could represented a serious threat for meteorological applications, in particular passive bands as well as meteorological radar (S, C and X bands)
WMO has been heavily involved in this issue in ITU-R TG 1/8 either on a European or international basis
Satisfactory outcomes, even though some administrations may not (or have not) follow the Recommendations
The final results in Europe are totally satisfactory since all meteorological bands are protected (UWB will be focusing in the GHz and possibly in the 3-5 GHz bands)
SG-RFC will issue a summary on UWB issues
WMO CBS-ISS
21 September 2006

24. Spectrum Overview WMO CBS-ISS 21 September 2006 1 2 3 4 5 6 7 8 9 10
GPR/WPR and imaging UWB devices
Communications and location tracking UWB devices 1 2 3 4 5 6 7 8 9 10 11
F (GHz)
Radiosondes and wind profilers
Wind profilers
MHz passive band
Radiosondes and METSAT
Weather radars
EESS (active)
GHz passive band
METSAT
GHz passive band
WMO CBS-ISS
21 September 2006

25. Public consultations
SG-RFC, has initiated a work to respond public consultations issued by radiocommunication bodies (National or Regional)
Responses are prepared by correspondence
Response to the Australian Administrations on a Decision related to SRR 24 GHz and RLAN 5 GHz : negative and positive outcomes
Response to the European Commission on a high level “Opinion” related to scientific use of the spectrum : positive outcomes
WMO CBS-ISS
21 September 2006

26. Handbook
The joint ITU/WMO handbook on “Use of radio spectrum for Meteorology” is widely recognised as an important tool for understanding our specific applications
It was issued in 2002 and certainly needs an update
SG-RFC is currently working on a revision, targeting a release prior WRC-07
Work is on-going since about 1 year and a specific SG-RFC meeting was organised 4th September
WMO CBS-ISS
21 September 2006

27. GEO
From the beginning, WMO is involved in GEO and in particular with regards to the protection of radio-frequencies
When GEO Task related to radio-frequency (AR-06-11) has been adopted, WMO evidently proposed itself to lead this task according to its current involvement in frequency management and in particular its ability to further positions at ITU-R level
SG-RFC chairman is now the Point of Contact (POC) of this task
Work is in progress and a general GEO “Resolution” will be prepared
WMO CBS-ISS
21 September 2006

28. Economical and societal impact
Facing powerful radio lobbies representing huge economical impacts, radiocommunication administrations are more and more undertaking “impact” analysis of the use of each frequency bands
The meteorological applications are not exonerated
SG-RFC has decided to draft a general document stressing societal and economical impacts of meteorology in the light of spectrum use
It will build upon in particular on materials presented during the discussions at European Commission levels (UK Metoffice, WMO,…),
All other information from members will be welcomed
WMO CBS-ISS
21 September 2006

29. Wind farms issue
In front of huge pressure and potential deployment of Wind farms, Meteo France has undertaken technical studies to determine their impact on meteorological radars *:
Blocking
Clutter
Doppler effect
These studies, confirmed by testing, shows that the worst impact is on Doppler, due to tremendous reflections on wind mills (RCS up to 30 dBsm)
Led to a specific report in France recommending exclusion (5 and 10 km) and coordination (20 and 30 km) distances for C and S band meteorological radars**
* similar studies are on-going in the US
** Similar recommendations are also made for Civil aviation and military radars
WMO CBS-ISS
21 September 2006

30. Wind farms issue Wind farms at 17 km Direct response without filtering
Wind farms responses
on main beam
Wind farms at 17 km
Direct response without filtering
Over 90° Azimuth
Confirms huge response and equivalent RCS of about 23dBsm
Highlight the huge impact over radar side lobes (radar sensitivity at about –15 dBz at 17 km)
And hence the Doppler impact
Wind farms responses on side lobes
WMO CBS-ISS
21 September 2006

31. Future work
SG-RFC will meet in 2007 prior the CPM tentatively mid January in the US (TBC)
Another meeting will certainly be organised prior the WRC
Of course, correspondence group is active that allows discussions in interim period
This is in particular important for preparing contributions and attendance to ITU-R meeting and in particular :
Working Party 8B (radars)
Working party 7B and 7C (meteorological applications)
this is of the utmost importance that WMO be represented (Either by Secretariat or SG-RFC members) each time meteorological interests are discussed
WMO CBS-ISS
21 September 2006

32. Conclusions
Radiofrequency matters is increasingly strategic for the meteorological community,
Currently, apart radiosondes, all spectrum usages related to the meteorological process are under threats, and in particular passive bands
Global involvement from WMO and members is mandatory, at national and international levels
SG-RFC is of course totally open for any details and support
Thank you for your attention
WMO CBS-ISS
21 September 2006