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Propagation-Radio-Waves

By Ashik


Radio Wave Propagation types



 
. Sky wave propagation
Waves in the HF range and some times frequencies just above or below it are reflected by the ionized layers of the atmosphere and therefore known as sky wave propagation. Sky wave comes down to the earth due to reflection at some distant point will beyond horizon.
Atmospheric Phenomenon
 
•Three layers:
–Troposphere:  earth’s surface to about 6.5 mi
–Stratosphere:  extends from the troposphere upwards for about 23 mi
–Ionosphere:  extends from the stratosphere upwards for about 250mi
–Beyond this layer is free space








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