Advertisements
Advertisements
Question
Is it necessary for a transmitting antenna to be at the same height as that of the receiving antenna for line-of-sight communication? A TV transmitting antenna is 81m tall. How much service area can it cover if the receiving antenna is at the ground level?
Solution
Line-of-sight communication means that there is no physical obstruction between the transmitter and the receiver. In such communications it is not necessary for the transmitting and receiving antennas to be at the same height.
Height of the given antenna, h = 81 m
Radius of earth, R = 6.4 × 106 m
For range, d = (2Rh)½, the service area of the antenna is given by the relation:
A = πd2
= π (2Rh)
= 3.14 × 2 × 6.4 × 106 × 81
= 3255.55 × 106 m2
= 3255.55
∼ 3256 km2
APPEARS IN
RELATED QUESTIONS
Write a short note on surface wave propagation of electromagnetic waves.
Line of sight propagation is also called as_________________ .
The reflected waves from an ionosphere are _____.
(a) ground waves
(b) sky waves
(c) space waves
(d) very high-frequency waves
Describe briefly, by drawing suitable diagram, the sky wave ?
An em wave is travelling in a medium with a velocity `vecv =vhati` Draw a sketch showing the propagation of the em wave, indicating the direction of the oscillating electric and magnetic fields.
Propagation of Electromagnetic Wave?
Answer the following question.
On what factors does the range of coverage in ground wave propagation depend?
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.
Explain the ground wave propagation and space wave propagation of electromagnetic waves through space.
The wavelength of electromagnetic wave employed in space communication very over a range of
The radio wave of frequency 300 MHz to 3000 MHz be.long to
Polarization in e.m wave is caused by
The Q of a resonant transmission line is
Propagation constant of a transmission line is
What is the value of frequency at which an e.m wave must be propagated for the D-region of atmosphere to have a refractive index of 0.49? Electron density for D-region is 109 m-3:
Two waves A and B of frequencies 2 MHz and 3 MHz, respectively are beamed in the same direction for communication via sky wave. Which one of these is likely to travel longer distance in the ionosphere before suffering total internal reflection?
