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  1. #1
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    Mixer topology--what is the purpose

    Hello all,

    Recently I've been studying about different mixers and their uses. I come across a mixer topology as in the image; can you share your opinions about what type of mixing does this perform?
    Click image for larger version. 

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    I'm assuming RF, LO and IF share the same ground as its not explicitly shown.


    Kind Regards,

    ktr

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  2. #2
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    Re: Mixer topology--what is the purpose

    This is a single-balanced mixer, and an equivalent circuit using transformers is shown below:


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  3. #3
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    Re: Mixer topology--what is the purpose

    Looks plausible, but I don't see how it works with a 90° hybrid.



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    Re: Mixer topology--what is the purpose

    90° hybrid is used at microwave frequencies when the transformer type at lower frequencies.

    This is typical single balanced mixer:

    http://www.rfcafe.com/references/ele...riminators.htm


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    Re: Mixer topology--what is the purpose

    Thanks. My fault was to assume that the IF would cancel like the DC component, but of course it doesn't.



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