Electronics and Communication Engineering - Exam Questions Papers - Discussion
Discussion Forum : Exam Questions Papers - Exam Paper 16 (Q.No. 2)
2.
At 20 GHz , the gain of a parabolic dish antenna of 1 meter diameter and 70% efficiency is
Discussion:
3 comments Page 1 of 1.
Jaswant sing said:
9 years ago
Please explain the solution.
Santhosh said:
8 years ago
The gain of a parabolic dish antenna, G=η√2(Dλ)2=(0.7).√2(13*10820*109)2,
G=30705.
In dB, G=10logG=45dB.
G=30705.
In dB, G=10logG=45dB.
(1)
CEPHAS MABVA said:
2 years ago
Using equation v=fλ.
it implies that λ=v/f=(3*10^8)/(20*10^9) = 0.015.
Gain of a parabolic dish antenna, G=Ae(πD/λ)^2 where Ae is the efficiency, D is the diameter, λ is the operating wavelength.
G = 0.7((π * 1/0.015)^2 = 30705.43591.
G in dB = 10log30705.43591.
= 44.87215267dB,
= 45dB.
it implies that λ=v/f=(3*10^8)/(20*10^9) = 0.015.
Gain of a parabolic dish antenna, G=Ae(πD/λ)^2 where Ae is the efficiency, D is the diameter, λ is the operating wavelength.
G = 0.7((π * 1/0.015)^2 = 30705.43591.
G in dB = 10log30705.43591.
= 44.87215267dB,
= 45dB.
(1)
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