Question

What is propagation explain diffrent type of propagations related to principle of electromagnetic waves

Answer 1

Propagation of Em Waves

When EM wave travel from transmitter antenna to receiver antenna through free space it is called the propagation of EM wave

There are three types of propagation of EM waves that is ground wave propagation, Sky wave propagation and space propagation

Ground wave propagation: when EM wave travel from transmitter antenna to receiver antenna along the surface of the Earth then it is called ground wave propagation and the wave is called ground wave. This wave operates at 3MHz and also known as surface wave.

This propagation depends upon Power transmitter and receiver, Frequency of transmission, condicondiof earth surface.

Sky wave propagation: in this propagation waves travel towards the sky and reflect back by the ionosphere to the Earth. Most of the radio communication happen in this propagation. The range of the Sky wave propagation is 3 to 30 MHz

This propagation is depend upon angle of radiation strength of ionosphere, power of transmitter.

Space Waves Propagation:

In this propagation electromagnetic waves are propagated from the transmitter antenna and it travels in a straight line without any reflection or refraction to reach receiver then it is called space wave propagation. This type of transmission is called Line of Sight transmission. The frequency of space wave is above 30 MHz and the distance covered by these waves is above 100 Miles or 121 km.