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Radio Wave Propagation

Radio Wave Propagation
After completing this instruction, the learner should be able to do the following:
  1. Describe the effect of the Earth’s atmosphere on radio waves
    • Troposphere
    • Stratosphere
    • Ionosphere
  2. Explain the two principal ways in which electromagnetic (radio) energy travels from a transmitting antenna to a receiving antenna.
    • Ground Waves
      • Surface Waves
      • Space Waves
    • Sky Waves
      • Structure of the Ionosphere
      • Ionization
      • Layers
        • D layer
        • E layer
        • F1 Layer
        • F2 Layer
      • Refraction in the Ionosphere
        • Density of the Layer
        • Frequency
        • Angle of Incidence
      • Skip Distance/Skip Zone
      • Propagation Paths
      • Absorption in the Ionosphere
      • Fading
        • Multipath Fading
        • Selective Fading
      • Transmission Losses
        • Ground Reflection
        • Free Space Loss
  3. Discuss the regular and irregular variations that affect the extent of ionization in the ionosphere.
    • Electromagnetic Interference
      • Man-made Interference
      • Natural Interference
    • Variations in the Ionosphere
      • Daily Variations
      • Regular Variations
      • Seasonal Variations
    • Eleven-year Sun Spot Cycle
    • 27-Day Sun Spot Cycle
    • Irregular Variations
      • Sporadic E
      • Sudden Ionospheric Disturbances
      • Ionospheric Storms
  4. Describe the frequency selection consideration for HF propagation.
    • Maximum Usable Frequency
    • Lowest Usable Frequency
    • Optimum Working Frequency
  5. Space Weather Variables and why they matter
    • Solar Effects on HF Propagation
      • Sunspots
      • Ionospheric Storms (Geomagnetic Storms)
      • Polar Cap Absorption Events (PCA)
      • Sudden Short Wave Fade (SSWF)
    • Space Weather Indices and other factors
      • K-Index
      • Kp Index
      • a Index
      • A Index
      • Ap Index
      • 10.7 cm flux
      • Sunspot number and Smoothed sunspot number (SSN)