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प्रश्न
What is ground wave communication?
उत्तर
Ground waves are the radio waves that travel along the surface of the Earth. In-ground wave propagation, a large portion of wave energy is in space near the surface of the Earth. The propagation of the wave is guided along the Earth's surface and follows the curvature of the Earth.
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संबंधित प्रश्न
Explain why ground wave communication mode cannot be used for long-distance communication using high frequencies
What is space wave propagation? Which systems of communication use space waves? What is 'radio horizon' of a transmitting antenna of height h? Why is space wave propagation suitable for frequencies above 40 MHz?
Is it necessary for a transmitting antenna to be at the same height as that of receiving antenna for LOS communication ?
Name the three different modes of propagation of electromagnetic waves. Explain, using a proper diagram the mode of propagation used in the frequency range from a few MHz to 40 MHz.
Explain with the help of a diagram how long distance communication can be achieved by ionospheric reflection of radio waves.
In sky wave mode of propagation, why is the frequency range of transmitting signals restricted to less than 30 MHz?
Light from a sodium lamp (S) passes through two polaroid sheets P1 and P2 as shown in fig. What will be the effect on the intensity of the light transmitted (i) by P1 and (ii) by P2 on the rotating polaroid P1 about the direction of propagation of light? Justify your answer in both cases.
What do you mean by skip distance?
A TV transmission tower has a height of 240 m. Signals broadcast from this tower will be received by LOS communication at a distance of (assume the radius of earth to be 6.4 × 106 m)
- 100 km
- 24 km
- 55 km
- 50 km
A 50 MHz sky wave takes 4.04 ms to reach a receiver via re-transmission from a satellite 600 km above earth’s surface. Assuming re-transmission time by satellite negligible, find the distance between source and receiver. If communication between the two was to be done by Line of Sight (LOS) method, what should size and placement of receiving and transmitting antenna be?
