Explain sky waves and space waves.

1.	Explain sky waves and space waves.
Answer» Sky waves: Long distance communication can be achieved by ionospheric reflection of radiowaves back towards the earth. Sky wave propagation and is used by short waves broadcast services. The ionosphere is so called because of the presence of a large number of ions of charged particles. It extends from a height of ~ 65 km to about 400 km above. Space wave: A space wave travels in a straight line from transmitting antenna to the receiving antenna.Space waves are used for line-of-right (LOS) communication as well as satellite communication. At frequencies above 40 MHz, communication is essentially limited to line-of-sight paths. At these frequencies,the antennas are relatively smaller and can be placed at heights of many wavelengths about the ground.

Answer»

Sky waves: Long distance communication can be achieved by ionospheric reflection of radiowaves back towards the earth. Sky wave propagation and is used by short waves broadcast services. The ionosphere is so called because of the presence of a large number of ions of charged particles. It extends from a height of ~ 65 km to about 400 km above.

Space wave: A space wave travels in a straight line from transmitting antenna to the receiving antenna.Space waves are used for line-of-right (LOS) communication as well as satellite communication. At frequencies above 40 MHz, communication is essentially limited to line-of-sight paths. At these frequencies,the antennas are relatively smaller and can be placed at heights of many wavelengths about the ground.

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