Spectrum Management

1
Aeronautical Spectrum Management
Aeronautical Spectrum Management Seminar Nairobi,
Kenya September 2007 Mike Biggs, US FAA
2
Spectrum Management Functions

• Chapter 6 of the ICAO Spectrum Handbook Provides
  an Overview
• Regulatory, Technical, Licensing and Registration
  Domains
• Day-to-Day
• Frequency Assignments
• Frequency Coordination (e.g., new-system testing)
• Radio Frequency Interference (RFI)
  Investigation/Mitigation
• See separate presentation
• Longer Term
• Analysis of future systems
• Both aeronautical and non-aeronautical systems
• Spectrum Allocations
• Both seeking new, and defense of existing,
  allocations
• World Radiocommunication Conferences and
  Preparations

3
Example FAA Spectrum Engineering Services
4
Aeronautical Frequency Bands

• Amount of Spectrum is Comparable to that
  Available for Maritime
• Much less than that allocated for broadcast and
  commercial communications
• General Recognition that Civil Aviation is a
  Global Enterprise
• ICAO Convention
• International Standards for Aviation Equipment
  (SARPs)
• Safety Implications have Historically Resulted in
  Exclusive Bands
• This model is under pressure from commercial
  interests

5
E.g., Bands Supporting Aviation
190 285 285 435 510 535
kHz Non-directional Beacons 2100 - 28,000
kHz HF Communications 74.8 75.2 MHz NAVAID
(Marker Beacons) 108 - 112 MHz VOR ILS
Localizer 112 - 118 MHz VOR GBAS (GNSS
augmentation) 118 - 137 MHz VHF Air/Ground
Communications 138 - 150.8 162 - 174
MHz Fixed, Mobile 225 - 328.6 335.4 - 400
MHz UHF Air/Ground Communications (State
a/c) 328.6 - 335.4 MHz ILS Glide Slope 406.1 -
420 MHz Fixed, Mobile 932 - 935 941 - 944
MHz Fixed 960 - 1215 MHz NAVAID (TACAN/DME,
etc.) GNSS UAT 1030  1090 MHz SSR (ATCRBS
Mode S) ACAS 1215 - 1390 MHz Air Route
Surveillance Radar GNSS at Ref Stations 1545 -
1559 MHz Satellite-Based Comm (To
Aircraft) 1559 - 1610 MHz GNSS 1610-1626.5
MHz Satellite-Based Comm (Iridium,
bi-directional) 1646.5 - 1660.5
MHz Satellite-Based Comm (From Aircraft) 1710
- 1850 MHz Fixed 2700 - 3000 MHz Airport
Surveillance and Weather Radar 5000 - 5150
MHz Microwave Landing System 5600 - 5650
MHz Terminal Doppler Weather Radar 7125 - 8500
MHz Fixed 9000 - 9200 MHz Surface Detection
Radar (ASDE-X) 14.4 - 15.35 GHz Microwave
Link 15.7 - 16.2 GHz Surface Detection Radar
(ASDE-3) 21.2 - 23.6 GHz Microwave Link
6
Day-to-Day (Frequency Assignments)

• Frequency Assignment Process Can Get Very
  Complicated. For example in the US
• Aeronautical Facilities
• Communication 14,383 facilities including 2,390
  radio sites
• Navigation 11,122 facilities including 1,027
  Very High frequency (VHF) Omni directional Range
  (VOR)
• Landing 1,375 Localizers
• Surveillance 1,882 facilities including 369
  radar sites
• Air Traffic Control Facilities
• Air Route Traffic Control Centers (ARTCC) 21
• Terminal Radar Approach Control (TRACON) 30
• Air Traffic Control Towers (ATCT) 518
• Automated Flight Service Stations (AFSS) 76
• Certificated Airports 575
• Certificated airports serve Air Carrier
  Operations with aircraft seating more than 9
  passengers seats.
• 37,763 frequency assignments to support these
  facilities!

7
FAA NAS Airspace
Complexity of Airspace Atlanta Center Airspace 46
three dimensional cells Each cell (called sector)
has a frequency protected VHF and UHF assignment
8
Frequency Assignments (cont)

• Complex airspace and sheer number of assignments
  call for structured process
• Standardized procedures based on equipment
  interference masks (e.g., ICAO standards and
  guidance material)
• Standardized models
• For more information on how this is accomplished
  in the United States, the FAA Spectrum Management
  Regulations and Procedures Manual can be found
  at
• http//www.faa.gov/about/office_org/headquarters_
  offices/ato/service_units/techops/spec_management/
  library/orders.cfm

9
Day-to-Day (Frequency Coordination)
Example Determine interference contours for
new-system trials. Use simulation models to
derive contours which are reflected in Notice to
Airmen (NOTAMs)
10
Longer Term (Analysis of Future Systems)

• To the extent possible, ICAO addresses
  interference immunity of aviation systems during
  system design
• Take into account the spectrum environment
• Build in resistance to RFI
• Case study on Universal Access Transceiver (UAT)
• Designed to operate in heavily-congested 960-1215
  MHz band
• Surveyed all existing users, cataloged signal
  characteristics
• Selected channel that was least-used on worldwide
  basis
• Tailored UAT signal/protocol to not-interfere
  with existing users
• Tailored UAT receiver front-end and signal
  error-correction to best mitigate operational
  environment (I.e., maximum protection from
  narrowband, pulsed signals)
• Iterative design assumptions verified via test
  and simulation
• Analysis of non-aviation systems is required to
  ensure their implementation will not interfere
  with aviation systems
• Generally concerned with out-of-band and spurious
  emission levels
• E.g., GNSS protection from mobile-satellite
  handset transmissions.

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Longer Term (Spectrum Allocations - 1)

• ICAO RF Handbook
• Chapters 5 and 6 deal with ICAO Involvement in
  Spectrum Planning and Management
• Commercial pressures to share bands
• E.g., Mobile communications (IMT advanced)
• Long aviation development time-lines may give the
  appearance of fallow spectrum
• E.g., Microwave Landing System (MLS) band
• Generally however, due to safety concerns, very
  limited potential for sharing aeronautical bands
• Failure Country footnotes allowing fixed
  service in GNSS band
• Success RNSS in 1164-1215 MHz, due mainly to
  very low RNSS signal levels
• Considerable technical effort going into
  maintaining current aviation spectrum.
• ACP WGF provides leadership within ICAO

12
Longer Term (Spectrum Allocations - 2)

• World Radiocommunication Conferences offer
  opportunities for changes to the International
  Telecommunicaiton Union (ITU) Table of Frequency
  Allocations
• For example, WRC-07 Agenda Item 1.6 offers
  potential for new AM(R)S allocations
• In order to be effective however, aviation must
  provide a united front in preparation for, and
  during, those Conferences. Administrations
  should be urged to
• provide experts from their civil aviation
  authorities to fully participate in development
  of States and regional positions, and
  development of aviation interests at the ITU and
• ensure, to the maximum extent possible, that
  their delegations to regional conferences, ITU
  Study Groups and WRCs include representatives of
  experts from their civil aviation administrations
  authorities or other aviation officials who are
  fully prepared to represent aviation interests
• Topic of Secretariat Paper to CIAO 36th Assembly
  (18-28 Sept, 07)