1. Ultra Wideband UK Test Results Presented by John Mettrop UK CAA
(Press)

2. What is Ultra WideBand? Short Duration Pulse
Occupies significant Bandwidth (Normally >500MHz)
High Instantaneous Power
Low average Power Flux Density
Intended to Operate Below Noise Floor

3. Ultra Wideband Applications (1)
Communications
3.1 – 10.6 GHz
Range <30 Metres
Bandwidth 480 MBits/Sec
Replacement of USB, Video Streaming
Ground/Wall Penetrating Radar
< 3 GHz
Range <2 cm to contact face
Road/Runway/Wall Assessment
Licensed and Co-ordinated

4. Ultra Wideband Applications (2)
Building Material Analysis
< 4 GHz
Range <1 Metre through Wall
Location of Pipes/Cables/ Imperfections
Intended to Be Unlicensed

5. Theoretical Studies ITU ECC TG1/8 Established in 2002
Completed it’s work in 2005
Produce 1 report and 4 Recommendations
ECC
PT 3
Report 64
ECC Decision
Further Consultation on PFD Limits 3.1 – 4.4 GHz
On-going Work on GPR/WPR/BMA
Due to Complete June 2006

6. Practical Testing in the UK

7. Aggregate Effects? Decreasing antenna gain UWB Devices ~300m
Radar Antenna 4° 2°
Sidelobes
Azimuth beamwidth ~2 to 4 degrees

8. Antenna Elevation Difference in antenna gain < 1dB One storey Two
building
Two
storey
building
Handheld
External?
Shielding
Glass 0 dB
Brick ~10 dB dB

9. Antenna Elevation Difference in antenna gain < 1dB
More important is number of devices rather than height
e.g. departure lounge. Eastleigh?
Shielding
Glass 0 dB
Brick ~10 dB dB

10. I/N versus UWB EIRP Radar IF Filter Response
Single UWB spike e.g. 50 MHz PRF
Multiple UWB spikes e.g. 1.5 MHz PRF
Shows how decreasing PRF or dithering can increase the I/N for a 20 MHz bandwidth

11. 1.5 MHz Undithered, 1 MHz bandwidth
Shows how decreasing PRF or dithering can increase the I/N for a 20 MHz bandwidth

12. Dithered UWB Undithered Dithered
Shows how decreasing PRF or dithering can increase the I/N for a 20 MHz bandwidth

13. Dithered UWB
Shows how decreasing PRF or dithering can increase the I/N for a 20 MHz bandwidth

14. OFDM UWB 1 MHz measurement bandwidth Bandwidth correction factor
channel width
1 MHz measurement
bandwidth
Bandwidth correction factor
for noise-like signals:
C = 10log10(BW ratio)
C = 10log10(5) = 7 dB
BW Ratio = Radar IF BW/1 MHz
Shows how decreasing PRF or dithering can increase the I/N for a 20 MHz bandwidth

15. Effect of Radar Processing on Interference Type
Radar return
pulse
20 dB
20 dB
50 MHz
undithered spike
Frequency
20 dB
Radar return
pulse
30 dB
OFDM
Shows how decreasing PRF or dithering can increase the I/N for a 20 MHz bandwidth

16. False Targets: Early Warning Mode
Targets start at 40 nm
Target spacing 2.5 nm
Shows how decreasing PRF or dithering can increase the I/N for a 20 MHz bandwidth

17. Determining Pd: 100% 5 targets, no interference
Shows how decreasing PRF or dithering can increase the I/N for a 20 MHz bandwidth

18. Determining Pd: 80% 4 targets
Shows how decreasing PRF or dithering can increase the I/N for a 20 MHz bandwidth

19. Determining Pd: 60% 3 targets
Shows how decreasing PRF or dithering can increase the I/N for a 20 MHz bandwidth

20. Determining Pd: 40% 2 targets
Shows how decreasing PRF or dithering can increase the I/N for a 20 MHz bandwidth

21. Determining Pd: 3 faint targets1 2 3
Shows how decreasing PRF or dithering can increase the I/N for a 20 MHz bandwidth

22. Pd vs EIRP: Radar B Uncorrected
Shows how decreasing PRF or dithering can increase the I/N for a 20 MHz bandwidth

23. Pd vs EIRP: Radar A Uncorrected
Shows how decreasing PRF or dithering can increase the I/N for a 20 MHz bandwidth

24. Correcting for wrong Pd
Shows how decreasing PRF or dithering can increase the I/N for a 20 MHz bandwidth

25. Correcting for wrong Pd
Measured at 90% +9.6 dB
Perform correction
Curve Fit Model for
90% dB
At 50% point
Model
Shows how decreasing PRF or dithering can increase the I/N for a 20 MHz bandwidth

26. Pd vs EIRP: Radar B Corrected
-90 dBm/MHz at 358m
-70 dBm/MHz at 358m
-56 dBm/MHz at 358m
~20 dB
Shows how decreasing PRF or dithering can increase the I/N for a 20 MHz bandwidth

27. Pd vs EIRP: Radar A Corrected
-53 dBm/MHz at 358m
-84 dBm/MHz at 358m
~30 dB
Shows how decreasing PRF or dithering can increase the I/N for a 20 MHz bandwidth

28. Distance correction Antenna near field effects ~ 100m?
First Fresnel Zone
At 3 GHz > 2 km
Field
strength
ITU Propagation Models
20 Log D1/D2
40 Log D1/D2
Distance
Shows how decreasing PRF or dithering can increase the I/N for a 20 MHz bandwidth

29. UWB Allowable Field strength vs Distance

30. UWB Allowable Field strength vs Distance

31. I/N versus EIRP: UWB to Radar B
Shows how decreasing PRF or dithering can increase the I/N for a 20 MHz bandwidth

32. Propagation: Onset of UWB interference

33. Key factors Setting of targets to 90% Pd
Determining when a target is visible
IF measurement bandwidth
Location of IF measurement in radar chain

34. Faulty Baby Alarms Purpose Potentially Affect Services
Monitoring baby activity during sleep
Potentially Affect Services
VHF Communications
Documented Cases of Interference
Numerous in the UK
Solution
Supply replacement unit
Studies
None

35. Industrial/Scientific/Medical 5th Harmonic of 27 MHz
Purpose
Various including RF drying ovens for biscuits etc
Potentially Affect Services
VHF Communications
Documented Cases of Interference
Numerous within the UK
Solution
Retune centre frequency of the RF unit
Better RF Shielding
Studies
None

36. Cable TV Purpose Potentially Affect Services
Provision of television and internet services
Potentially Affect Services
ILS, VOR, VHF Communications
Documented Cases of Interference
Numerous in Germany and Belgium
Initial Problems in the UK
Solution
Improved termination of cables
Frequency avoidance
Studies
ECC Report 24
May 2003

37. Wireless Cameras Purpose Potentially Affect Services
Wireless CCTV cameras
Potentially Affect Services
DME, SSR, GNSS
Documented Cases of Interference
See WG F Working Paper 9
Solution
Confiscation
Prosecution
Studies
None

38. GSM On-board Aircraft Purpose Potential Impact Studies
Provide mobile phone communications in flight
Potential Impact
Interference to Aircraft Systems
Passenger Behaviour (Air Rage)
Interference to Ground Non-Aeronautical Services
Studies
RTCA 202 (on-going)
Eurocae WG58 (on-going)
CEPT SE 7 Technical Report (on-going)

39. Windfarms 1 Purpose Potentially Affect Services
Renewable Energy Provision
Potentially Affect Services
Radar
(ILS, MLS, VHF Communications)
Documented Cases of Interference
See next slide
Solution
Objection to Development
Studies
None published
Work on-going

40. Windfarms 2

41. Questions