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  • Question

  • The cut off wavelength in circular waveguide


  • Options
  • A. guide diameter
  • B. square of guide diameter
  • C. cube of guide diameter
  • D. square root of guide diameter

  • Correct Answer
  • guide diameter 

    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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