Wave probigation

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For a course for an amateur radio license.

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Wave probigation

  1. 1.  Waves and ionisation  Atmosphere  Ionosphere  Troposphere  Other methods
  2. 2.  Electromagnetic energy  Models  Waves  Particles  Electrical part  Magnetic part  Polarisation  Vertical  Horizontal
  3. 3.  Ion  Protons != electrons  Ionisation  Removal or addition of an electron  Energy
  4. 4.  Troposphere  Ground to 7-17 km out - Temp dec. with height  80% of the mass  Stratosphere  About 51 km out – Temp inc. with height  Mesosphere  80-85 km out – temp at – 85 deg C  Thermosphere  350 – 800 km out – temp +1 500 Deg C  Exosphere
  5. 5.  Troposphere  Thermosphere  Exosphere ionosphere
  6. 6.  100 – 300 km  Ionisation of particles  Sun  Thin atmosphere  Shell of electrons  Layers  Radio propagation  “acts like a mirror”  At certain frequencies
  7. 7.  D layer  Ionising NO (some N2 and O2)  Electron collision high  Results in blocking of HF radio waves  < 10 MHz  Almost disappears after sunset  HF can pass through if broadcasted directly up
  8. 8.  E (Heavyside) layer  Ionisation of O2  Refracts radio waves < 10 MHz  Nordic area  At night, increasing height inc. range  Es layer  Sporadic – best during the summer  Refracts up to 50 Mhz  Distance of 1000 km
  9. 9.  F (Appleton) layer  Ionising of O – dense  Refracts most HF radio waves (3-30 MHz)  Skywaves  F1 and F2 layers  Exist during the day
  10. 10.  Fading  Changes in the ionosphere  Changes the polarisation  Angle  Critical angle  Depends on ionosphere and frequency used  Hi angle and Hi F pass through.
  11. 11.  Nordic region  3.5 – 7 MHz  Dipole  Straight out  Using D layer  14 – 30 MHz  Uses E and F layers (low elevation angle)  2 000 – 4 000 Km
  12. 12.  DX traffic  DX – distance  Dipole or yagi array  For Europe  30 Deg  0.5 Wave length  Out side Europe  1 -2 X wave length  10 Deg 1.5 X wave length
  13. 13.  Its damp!  99% of the water vapour!  Effects radio transmissions  Hi F = more absorption  Used for VHF, UHF and SHF transmissions  Line of sight  20- 30 km (depends on power)  Can scatter (refraction)  Up to 2 000 km
  14. 14.  Earth-Moon-Earth (EME)  144 MHz, 434 MHz and 1 296 MHz  As far away as Australia!  Meteors  Same as EME  Short burst  Auroras  > 25 MHz  NW -> NE aerial

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