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    Questions to SATCOM antennas

    Hello,

    I have questions to the two attached presentation slides.

    Slide 1: Why is C band antenna diameter much larger than L, Ku and Ka ones?

    Slide 2: It is included that antennas for TDMA are greater than for spreading spectrum. As far as I know different antennas have different patterns, but why do transmission modes play a role?

    Could anybody kindly explain these for me?

    Senmeis

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    Re: questions to SATCOM antennas

    Quote Originally Posted by senmeis View Post
    Hello,

    I have questions to the two attached presentation slides.

    Slide 1: Why is C band antenna diameter much larger than L, Ku and Ka ones?

    Slide 2: It is included that antennas for TDMA are greater than for spreading spectrum. As far as I know different antennas have different patterns, but why do transmission modes play a role?

    Could anybody kindly explain these for me?

    Senmeis
    because that is how you get the required gain

    the higher in freq you go, the smaller the antenna needs to be to get the same amount of gain


    not sure ion the second question



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    Re: questions to SATCOM antennas

    KVH , uses shorter wavelength Ku band than C-band using traditional TDMA which used a modulation that uses more bandwidth per channel.
    A good design question lists your overall requirements™ The best question deserves a better answer. ™
    ... Tony Stewart EE since 1975



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  4. #4
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    Re: questions to SATCOM antennas

    Quote Originally Posted by davenn View Post
    because that is how you get the required gain

    the higher in freq you go, the smaller the antenna needs to be to get the same amount of gain


    not sure ion the second question
    But L < C < Ku.



  5. #5
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    Re: questions to SATCOM antennas

    I think you refer to the relationship:

    G ~ A/λ˛

    But λC < λL

    Senmeis



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