Explain ground wave propogation with neat sketch.

Explain ground wave propogation with neat sketch. 
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Answer :

Sketch-

image 

Explanationi) It consists of direct wave which travels near the ground from Transmitter to Receiver. ii) The electromagnetic wave leaves the transmitting antenna & remains close to earth surface. The ground wave actually follows curvature of earth & hence travels beyond the horizon iii) The ground waves are vertically polarized. iv) It is strongest at the low & medium frequency ranges. The ground wave is the path chosen when frequency in between 30 KHz & 3 MHz 

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