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  1. #1
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    log periodic antenna calculator

    hi guys,complete design of log periodic antenna here

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    log periodic calculator

    I'm check this calculator and I can said that this simple calculation isn't correct or not agree with EM simulation and measurements.

    Anyway, LPDA structure check firstrly in any wire based codes(MOM) and on the end in full 3D based. Impedance is very critical(wire method isn't correct) and because use full 3D simulator.


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  3. #3
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    lpda antenna calculator

    What I am getting is the longest element is just resonant at the low frequency end and the far end of the array is resonant way above the highest frequency. I have tried radically different frequency ranges and tau values



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  4. #4
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    lpda calculator

    Hi flatulent

    If you are looking for good LPDA calculator you can find
    it in PCAAD Ver.5 and a lot of other good stuff see in

    http://www.antennadesignassociates.com/pcaad5.htm



  5. #5
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    log periodic antenna construction

    Read this book https://www.edaboard.com/viewtopic.p...highlight=lpda

    AND

    Use EZNEC, MMANA or SuperNEC (working with Matlab) to simulate it


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    Re: log periodic antenna calculator

    Quote Originally Posted by abdoeng
    hi guys,complete design of log periodic antenna here
    Hello, abdoeng,

    I'm trying to build in domestic conditions LPDA antenna like on the attached picture (Lectrosinics ALP500), but am having some difficulties with the measurements.

    Also, I checked your excel formula, but it's designed for tube LPDA.

    Could you, please, help me with correct sizes and proportions for this model?

    Thanks in advance.



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    Re: COMPLETE DESIGN OF LOG PERIODIC ANTENNA

    hello,
    i'm triying to design log periodic antenna but i dont know how to start. below is the detail info:
    frequency 1GHz ~ 6GHz.

    can anybody can help me how to design and the calculation.


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  8. #8
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    Re: COMPLETE DESIGN OF LOG PERIODIC ANTENNA

    length of the largest dipole: L1=λmax/2 (λmax corresponding to fmin)
    length of the smallest dipole: LN=λmin/2 (λmin corresponding to fmax)

    geometric ratio: τ=L(n+1)/Ln
    spacing factor: σ=dn/(2*Ln) , where dn is the spacing between dipole number n+1 and dipole number n .

    Ln=L1*τ^(n-1)
    dn=d1*τ^(n-1)

    you can find these formulas in Balanis's Antenna book.



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