1. CRES Amateur Radio Club
Wave Propagation
Presented by:
Bob Kenyon - K8LJ
CRES Amateur Radio Club
4/22/2008

2. Agenda Introduction and background Basic propagation concepts
Propagation software overview
Modeling program examples
Demo of W6ELProp and Ionoscope
Open discussion & conclusion

3. Primary Propagation Modes
Ground wave
AM BC band daytime; HF across town
Space wave
Point to point (ground not involved)
Sky wave (the focus of this presentation)
Refraction via the ionosphere
Makes world-wide
communications possible
Satellite communications
Artificial propagation (repeater in the sky)
~ 30 mi.

4. Other Propagation Modes
Back scatter and side scatter
Rain scatter
Tropospheric scatter
Tropospheric ducting
Meteor scatter
Gray line (day - night line)
Aurora
Moon bounce

5. Some Basic Concepts Wave Reflection
- Occurs primarily at earth’s surface
Wave Refraction
- Bending that occurs in the ionosphere and elsewhere
Wave Diffraction
- Bending over the earth’s surface or around obstacles

6. Reflection and Refraction=

7. Diffraction Around and Over an Object
(Not to scale) . .

8. The Earth and Environs Ionosphere 250 miles 23 miles 6.5 miles Earth
(Not to scale)
Ionosphere
250 miles
23 miles
6.5 miles
Earth
Troposphere
Stratosphere*
* Isothermal region

9. Layers of the Ionosphere
(Not to scale)

10. Ole Sol (The Sun)
A massive nuclear furnace which produces the following:
Visible light (what we can see)
Ultraviolet light (ionizes the F layer)
Soft X-rays (ionizes the E layer)
Hard X-rays (ionizes the D layer - RF sponge)
Solar wind (charged particles that impact the earth’s magnetic field
Solar flares & coronal mass ejections (CMEs)
Sunspots (increases ionization of the F layer)

11. The Electromagnetic Spectrum
Increasing Wavelength
Increasing Frequency
Optical
Window
Radio
Window

12. Delay 15 min – Several Hours High Energy Protons &  Particles
Solar Flare Ionospheric Effects
Sun
Electromagnetic
Radiation Increase
Delay 8. 3 min
Solar Cosmic Rays
Delay 15 min – Several Hours
Magnetic Storm
Particles
Delay Hrs
High Energy Protons &  Particles
Low Energy Protons
And Electrons
Ultraviolet
And X-Rays
D-Layer
Increase (SWF)
D –Layer
Increase (PCA)
Magnetic
Storms
Sporadic E
D – Layer Increase
(Auroral Absorption)
Auroras
SWF = Short Wave Fading
PCA = Polar Cap Absorption

13. Some Propagation Terms
Critical Frequency
The highest frequency returned to earth when transmitted vertically
Critical Angle
The highest angle at a given frequency which will be returned to earth
Maximum Useable Frequency (MUF)
The highest frequency returned to earth between two specific points
Skip Zone
Area between the ground wave end and 1st sky wave reception

14. Frequency vs. Ionospheric Refraction

15. Frequency vs. Critical Angle

16. Critical Angle and the Skip Zone

17. Close-up View of Actual Sunspot
Taken by NSO Sacramento Peak Vacuum Tower Telescope

19. 100,000
Kilometers

22. More Propagation Terms
Sunspot number (SN)
- Weighted average of actual sunspots and groups of sunspots
Smoothed sunspot number (SSN)
- SN averaged over + and - 6 months (13 months)
Solar flux
- Measurement of solar radio noise at 2800 MHz. (10.7 cm)
K index (Kp index - planetary)
- A mid latitude geomagnetic index updated every 3 hours (scale 0 - 9)
A index (Ap index - planetary)
- A daily measure derived from the K index (scale )

23. Some General Principals
Sunspot impact is a long term phenomenon
- Observe months and years, not hours or days
Geomagnetic activity is more short term
- Hours or even minutes can be very important
Use the planetary (Kp and Ap indices)
A K Conditions
0 0 Quiet
2 1 Quiet
3 1 Quiet
4 1 Quiet to unsettled
7 2 Unsettled
15 3 Active
27 4 Active
48 5 Minor storm
80 6 Major storm
132 7 Severe storm
208 8 Very major storm
400 9 Very major storm

24. Guide to Propagation Conditions Using Solar Indices

25. Smoothed Solar Flux vs. Smoothed Sunspot Number (SSN)

26. Penticton, B.C. 10.7 cm Solar Flux Monitoring Facility
(2800 Mhz)

27. Smoothed Solar Flux vs. Smoothed Planetary A Index

28. Last Sunspot Cycle (23)

29. Comparison of Last Three Solar Cycles (21, 22, & 23)

30. 400 Years of Sunspot Observations
Pilgrims Land at
Plymouth Rock
American
Revolution

31. Solar Cycle 24 Sunspot Number Prediction

32. Future Sunspot Cycle Predictions

33. Propagation Software W6ELProp V2.7 (demo next) VOACAP HFx V. 1.1 $129
(Sample)
Public Domain (Free)
W6ELProp V2.7 (demo next)
VOACAP
Commercial
ASAPS V. 4 $275
HFx V $129
CAPMan $89
WinCAP Wizard 2 $29.95
PropLab Pro $150

34. Demonstration of
W6ELProp V2.7
and
Ionoscope

35. Conclusion

36. References
(1) Davies, K., Ionosopheric Radio, London: Peter Pereginus, 1989.
(2) The ARRL Antenna Book, Newington, CT: ARRL, 2002
(3) Jeffrey S. Beasley & Gary M. Miller, Modern Electronic
Communication, 9th Edition, Columbus, OH: Prentice Hall, 2008
(4) Jacobs, G., Cohen, T., Rose, R., The NEW Shortwave Propagation Handbook,
CQ Communications, Inc., Hicksville, NY: 1995
(5) The ARRL Handbook, Newington, CT: ARRL, 2002
(6) McNamera, L.F., Radio Amateur’s Guide to the Ionosphere,
Malabar, FL: Krieger Publishing Co., 1994