International Civil Aviation Organization Regional Preparatory Group RPG Meeting for World Radiocomm

1
International Civil Aviation OrganizationRegional
Preparatory Group (RPG) Meeting for World
Radiocommunication Conference 2007 (WRC-2007),
ACP Working Group B and F and NSP SSG Meetings.
Bangkok, Thailand, 21-25 February
2005.RPG/ACP/NSP pres4

• Agenda Item 5
• SPECIFICS ON FM BROADCAST INTERFERENCE AND LATEST
  WORK
• presentation by
• Steve Mitchell

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A LITTLE BIT OF HISTORY

• Changes to ITU Radio Regulations
• recognition of potential interference to
  aeronautical systems
• studies within the ITU
• initial studies
• further enhanced studies
• final ITU recommendations

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GENERAL TYPES OF INTERFERENCE

• Four types of interference to consider
• Type A
• A1
• A2
• Type B
• B1
• 2 signal
• 3signal
• B2

4
DIFFICULTIES WITH ILS/VOR/COM

• Extensive testing
• ILS/VOR receivers
• 3rd order intermodulation
• saturation
• Com receivers
• ICAO Annex 10 SARPs requirements
• 3rd order 2 signal
• Desensitisation

5
DIFFICULTIES WITH GBASAND VDL 4

• Testing of GBAS and VDL 4 receivers
• same mechanisms apply as for ILS/VOR/COM
• avionics manufacturers tests above 112 MHz
• split in desensitisation requirements
• similar A1and B1 criteria as ILS/VOR
• ICAO Annex 10 SARPs requirements
• 3rd order 2 signal
• Desensitisation

6
Co-ordination

• Why co-ordination?
• Between FM broadcasters
• mutual sharing
• Between FM broadcasters and aeronautical
• avoid interference to aeronautical services
• Between aeronautical and FM broadcasters
• avoid potential problems

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Example of co-ordination process

• Example of an approach to co-ordination
• European example
• inside a State
• databases
• computer tools
• agreement mechanism
• between States
• LEGBAC/EBU

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TYPE A1 CALCULATION
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TYPE A2 CALCULATION
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TYPE B1 CALCULATION2 SIGNAL
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TYPE B1 CALCULATION3 SIGNAL
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TYPE B2 CALCULATION
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TRIGGER AND CUT-OFF CALCULATIONS
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ILS PROTECTION
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VOR PROTECTION
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CURRENT STATUS OF WORK

• ITU
• Working Party 8B
• Development of new recommendation
• Information on interference to FM receivers
• ICAO
• NSP SSG
• ICAO input to ITU

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FURTHER WORK WITHIN ICAO

• ILS
• GBAS
• No compatibility shown
• VDL 4
• No compatibility shown