Propagation

• Ground Wave follows the earth’s contour due to diffraction and is not reflected.  Most apparent at LF
• Sky Wave (ionospheric wave) returns to earth after being reflected by an ionised layer.  At low frequencies liable to absorption by the D layer
• Skip Distance is the distance between the transmitter and the nearest point on the earth that the sky wave can be received
• Skip Distance is dependant on the angle of radiation from the antenna and frequency.  Lower angle gives longer skip distance
• Dead Zone is the distance between the end of ground wave propagation and the nearest point on the earth that the sky wave can be received

Course Guide Topics

1. Electric Field
2. Magnetic Field
3. Electromagnetic Field
4. Propagation Velocity
5. Signal Attenuation
6. Atmospheric Layers
7. Ionospheric Layers
8. Ionosphere – diagram
9. Layer Properties
10. Ground and Sky Waves
11. Skip Distance
12. MUF
13. LUF
14. Critical Frequency
15. Fading
16. Sunspots & Flares
17. Troposphere
18. VHF/UHF Propagation
19. Line of Sight Propagation
20. Diffraction