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WRC-07 Decision on C-band. Kristen Kloster Director, International Programmes Global VSAT Forum. The ITU Radio Régulations. One of their main purposes - Interference-free operation of RadioComms Lengthy & complex procedure Established / amended by States during WRCs (every 3-4 years);
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WRC-07Decision on C-band Kristen Kloster Director, International Programmes Global VSAT Forum
The ITU Radio Régulations • One of their main purposes - Interference-free operation of RadioComms • Lengthy & complex procedure • Established/amended by States during WRCs (every 3-4 years); • Opportunity to resolve interference before operation; • Prevents loss of investment, customers & revenue from unusable capacity due to interference.
WRC Agenda Item 1.4 • “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)”
IMT Candidate Frequency Bands • ITU-R WP 8F • IMT Candidate Frequency Bands • 410 – 430 MHz • 450 – 470 MHz • 470 – 806/862 MHz • 1 518 – 1 525 MHz • 1 668 – 1 675 MHz • 2 300 – 2 400 MHz • 2 700 – 2 900 MHz • 3 400 – 4 200 MHz • 4 400 – 4 990 MHz
3.4 3.5 3.6 3.7 3.8 3.9 4.1 4.2 4.0 Std. C Ext. C Band commonly used by FSS satellites Additional band (FSS, feederlinks for MSS, …) C-band Downlinks
WRC-07 Agenda Item 1.4 • Key Issue at WRC-07 • Many Issues only Resolved on Penultimate Day of Conference
BWA vs FSS • The sharing situation was extensively studied, in particular in response to agenda item 1.4 of WRC-07 (“IMT”). • Several compatibility issues were identified: • Blockage of reception in same frequency band (“in-band”); • Blockage of adjacent frequencies (“out-of-band”); • Overload of satellite receiver (“saturation”). • Main issue = “in-band”
The Findings • Numerous practical tests have shown that FSS and WiMAX cannot coexist in the same or adjacent bands • SUIRG • CEPT • Hong Kong • Tanzania • Bolivia • Australia • Fiji • Argentina • etc
The Findings • BWA or IMT in a part or all of the FSS C-band downlink will be incompatible with general FSS reception in any part of C-band in the same geographical area • BWA or IMT in a part of C-band may be compatible with FSS reception by a small number of earth stations if: • Appropriate exclusion zones around each of the earth stations are established • User terminals are designed not to emit any signals when not in contact with a base station • Introduction of BWA or IMT by one country can block FSS reception in another country
Solutions identified (1/2) • Separation distances between BWA and FSS receiving earth stations, using criteria defined by ITU. • Examples of separation distances: • “in-band”: several tens of km (up to > 100 km); • “out-of-band”: few kilometers (up to 2 km); • “saturation”: several hundreds of meters (up to > 1 km).
Solutions identified (2/2) • Since individual licenses are not usually required for FSS earth stations such as TVRO terminals, which have divers retail outlets, there is no central record of their locations. Therefore it is not feasible for BWA to share with them in the same geographical area since no minimum separation can be guaranteed. • Separation distances could be reduced by implementing appropriate mitigation techniques (where applicable), but most of these would not reduce the distances to zero and the others have yet to be shown to be practicable
C-Band Earth Stations in Africa (3400-4200 MHz)(Incomplete Count from Intelsat)
FSS Earth stations in Europe The sites shown are those recorded by Intelsat and SES/New Skies in the band 3400-4200 MHz – (1081 terminals, 694 sites). Additionally many TVRO earth stations exist but are unrecorded and thus unable to be shown here. Furthermore the map does not show earth stations served in this band by other satellite operators.
Importance of C-Band to the FSS • Only band where FSS can be provided with high reliability in areas with high intensity rainfall • Large area coverage – ideal for developing countries • Standard C-Band is fully utilised – developing countries are dependent on extended C-Band • Ku- and Ka-band satellite systems suffer from rain fade problems and are more suited for smaller coverages
The WRC Outcome • No global identification for IMT • C-Band preserved for satellite use • Individual countries can take a different position to the international community and sign up to ‘country footnotes’ that offer… • In Region 1: 3 400 – 3 600 MHz is allocated to mobile services and identified for IMT for some countries • In Region 2: 3 400 – 3 500 MHz is allocated to mobile services • In Region 3: 3 400 – 3 500 MHz is allocated to mobile services and identified for IMT for some countries, as is 3 500 – 3 600 MHz
The WRC Outcome • 3400 – 3600 MHz ADD MOB/IMT ADD 5.AAA • Mobile allocation in 3400 – 3600 MHz is effective 17 November 2010 • IMT is subject to RR 9.17; RR 9.18; + pfd limits
The Ongoing Threat to Satellite Operations • At WRC-07 only 200 MHz allocated to IMT in C-Band • ITU-R WP 5A studying compatibility between BWA & FSS in C-Band
How C-band Will be ‘Protected’ • Any deployment of IMT services in the C band must fulfil strict criteria laid out in the country footnote 5.AAA: • Careful limits are placed on the power flux density allowed at the border between countries that choose to allow the deployment of IMT services and countries that follow the norm • Existing rules governing sharing between services are reaffirmed to make sure they are applied when necessary - to help protect both existing and future satellite services • There are currently no future agenda items to revisit this issue