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The radiation pattern of an antenna in spherical coordinates is given by F(θ) = cos4 (θ), 0 ≤ θ ≤ . The directivity of the antenna is

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UPSC ESE (Prelims) Electronics and Telecommunication Engineering 19 Feb 2023 Official Paper
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  1. 16.42
  2. 18.02
  3. 20.42
  4. 22.02

Answer (Detailed Solution Below)

Option 2 : 18.02
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Directivity of antenna:

The directivity of an antenna is a measure of its ability to focus or direct radiation in a specific direction. It is related to the radiation pattern and is often given by an integral over the pattern. The higher the directivity, the more concentrated the radiation in a particular direction.

Prad  = 

Prad = 

Prad = 

Prad = 

Gd = 

D = Gd max = 

Here, option 2 is correct.

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