1. Radio Frequency Interference
Spectrum Management Seminar
Nairobi, Kenya
September 18, 2007
Mike Biggs
Senior Engineer
FAA Spectrum Engineering Services

2. What is Radio Frequency Interference (RFI)?
ITU Definition: The effect of unwanted energy due to one or a combination of emissions, radiations, or inductions upon reception in a radiocommunication system, manifested by any performance degradation, misinterpretation, or loss of information which could be extracted in the absence of such unwanted energy.
Criteria to mitigate inter-system interference are established as an element of ICAO SARPs.
E.g., 8 dB D/U for co-channel DME assignments

3. US RFI Yearly Activity Statistics
1995 Events = 1109
1996 Events = 1248
1997 Events = 1398
1998 Events = 1576
1999 Events = 1596
2000 Events = 1771
2001 Events = 1721
2002 Events = 1659
2003 Events = 1698
2004 Events = 1712
2005 Events = 1642
2006 Events = 1696
ICAO Spectrum Management Seminar
September 2007

4. RFI Categories Authorized Transmissions Unauthorized Transmissions
Properly Licensed (i.e. FM, AM, TV)
Unauthorized Transmissions
Wireless Video Cameras
High Power Cordless Telephones
Unlicensed Pirate FM Stations Spurious
Intentional
Unauthorized Jamming
“Phantom” Controllers
Unintentional
Spurious Transmissions
ICAO Spectrum Management Seminar
September 2007

5. RFI Sources Citizens Band (CB) Radios (5th harmonic) Paging Systems
Stuck Microphone Transmissions
Cell phone Spurious Emissions
Electronic Attack (EA) Missions
Power line Noise (Broadband Noise)
Anomalous Propagation
Atmospheric Conditions
Amateur “HAM” Radio
Land Mobile/Dispatch
ICAO Spectrum Management Seminar
September 2007

6. US National Airspace System RFI
Most Common Source of RFI:
Unauthorized Transmissions
Pirate FM Broadcast Spurious
Most Common FAA Victim:
VHF/UHF Voice Communications
Most Difficult RFI to Resolve:
High Altitude Pilot Only Reported RFI
Intermittent RFI (Airborne/Ground)
Broadband RFI on Many Frequencies
Phase Shift Keying RF Transmissions
ICAO Spectrum Management Seminar
September 2007

7. US RFI Investigation Resources
FAA Personnel and Organizations:
ATC Spectrum Engineering Services
Headquarters
Technical Center
Command Center
Frequency Management Officers (FMO)
Technical Operations Service Areas
Aeronautical Center
Technical Support Field Specialists (Technicians)
Aviation System Standards (Flight Inspection)
One International FIO
Six National FIOs
ICAO Spectrum Management Seminar
September 2007

8. Regional Used mainly by FMOs Most Complete Measurement System
RFI Investigation Resources
FAA Assets and Software Tools
Radio Frequency Interference Monitoring (RFIM) Vans
Automated or Manual
Full Equipment Suite
DF Control/Mapping
MHz
Regional Used mainly by FMOs
Most Complete Measurement System
ICAO Spectrum Management Seminar
September 2007

9. Automated Vehicle mounted mobile DF
Portable DF (RFID)
29 RFID
Systems
GPS DF Antenna
L MHz
Regional
Automated Vehicle mounted mobile DF
Detection Band MHz
ICAO Spectrum Management Seminar
September 2007

10. Handheld DF (K95-103) Regional
Most Cost effective First choice instrument for technicians
Approx. 300
K Systems
GPS DF Antenna
L1,L2,L5
VHF Yagi Antenna
Directional
Regional System Management Office (SMO)
33 Offices in the NAS
K Detection Coverage
20 – 3000 MHz
Typically 2 miles
ICAO Spectrum Management Seminar
September 2007

11. Airborne DF (OAR-4400) DF Control/Mapping Operated Automation
GPS DF Array & VHF DF Array
L1,L2,L5 & MHz
AVN
Flight Check NASE/RFI Program to assist in locating RFI/GPS sources
First Choice when High Altitude PIREPS ONLY
ICAO Spectrum Management Seminar
September 2007

12. National RFI Initiative
FAA Assets and Software Tools
Los Angeles (LAX), Chicago (ORD), New York (JFK), Miami (MIA)
FAA Intranet Web based Graphical User Interface (GUI)
Web Browser Control of Fixed DF and Spectrum Analyzer
New York
NIMDS
Miami
Master
IMDS
Chicago
Los Angeles
ICAO Spectrum Management Seminar
September 2007

13. Interference Monitoring Detection System (IMDS)
WEB IMDS
Receiver Tuned Frequency
DF Processor Bearing Averaging Triangulation
Multiple Audio Playback Capability
Synchronized Spectrum Analyzer Spectral View
ICAO Spectrum Management Seminar
September 2007

14. Mapping Triangulation
WEB IMDS
Triangulated Bearing Averages Overlay on Map
Increases Fix Calculation Ellipse Accuracy
Multiple Ellipse Calculation for Smaller Ellipse
ICAO Spectrum Management Seminar
September 2007

15. New IMDS Version 2.0 Control
ICAO Spectrum Management Seminar
September 2007

16. Example Engineering Analysis Tools
Automated Frequency Manager (AFM)
Flight Explorer Aircraft Situation Display (FE ASD)
Space Loss Calculator (SPLC)
Spectrum Engineering Tracking System (SETS)
Various Government Database Systems
Government Master File (GMF)
FCC Wireless Frequency Database
ICAO Spectrum Management Seminar
September 2007

17. Flight Explorer ASD Aircraft Situation Display (ASD)
Traffic Flow of potential aircraft PIREPS
RLOS Footprint
Lowest Aircraft Altitude
VENN Diagram Overlay Area
ICAO Spectrum Management Seminar
September 2007

18. Determine the potential signal levels received by Aircraft
Space Loss Calculator
Propagation
Loss
Determine the potential signal levels received by Aircraft
Analyze:
Intermodulation
FM Worksheet
Site Specs
Soil Conductivity
ICAO Spectrum Management Seminar
September 2007

19. Used for Matching with known
Audio Spectrogram Analysis
Audio
Detection
Visual
Intensities
Used for Matching with known
sources
Audio Spectral Views
ICAO Spectrum Management Seminar
September 2007

20. Maintenance Management System
Facility ID Start Date/Time Summary
Cause Code 84 Code 7 RFI Events Logged
ICAO Spectrum Management Seminar
September 2007

21. Event Manager Reporting Tool
Facility ID Start Date/Time Summary
NOCC Code 84 Code 7 RFI&GPS Events Logged
Tracked & Updated Daily by FAA ASR Liaison
ICAO Spectrum Management Seminar
September 2007

22. aeroRFI – Internet Reporting
Commercial and
Private
Pilots Reporting
Special
aeroRFI
Team
Internet
Messaging
ICAO Spectrum Management Seminar
September 2007

23. RFI/GPS Reporting Flow
RCL/LMR
NAV RFI
ILS
GPS
RADAR RFI
ENROUTE
TERMINAL
NAS Services Impacted - Reported By Users
MMS NAPRS Reports
NOCC EM Reports
Spectrum Engineering Tracking System (SETS)
Intranet FAA Network Records
Linked
NOCC Phone – Reports
aeroRFI Reports
Private Pilots Network
Liaison Reports
Field Personnel Reporting
COMM RFI
ICAO Spectrum Management Seminar
September 2007

24. Spectrum Engineering Event Tracker
Open Active Events Report
Search Code 84 RFI Events Fields
Drop Down Selection for Search Execution
ICAO Spectrum Management Seminar
September 2007