In a circular waveguide with radius r, the dominant mode is TM01 TE01 TM11 TE11

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Question
In a circular waveguide with radius r, the dominant mode is
Options
A. TM₀₁
B. TE₀₁
C. TM₁₁
D. TE₁₁

Correct Answer

TE₀₁

Explanation

Some applications require dual polarization capability. Circular waveguide has this capability.

These analysis uses cylindrical coordinates.

In circular waveguide TE₁₁ mode has the lowest cut off frequency and is the dominant mode.

If D is diameter of waveguide

?_c = 1.706 D for TE₁₁ mode

?_c = 1.029 D for TE₂₁ mode

?_c = 0.82 D for TE₀₁ mode

?_c = 1.306 D for TM₀₁ mode.

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Options
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Options
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Options
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Options
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Options
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8. As compared to LED, LASER has
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2. no tuning arrangement
3. narrow spectral width
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Options
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