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    mixer output phase noise and jitter

    assume that the two input to the mixer are of same frequency and same phase noise, the output frequency will double. what is the relationship between output frequency jitter and input jitter?
    are they the same?

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    Re: mixer output phase noise and jitter

    If the frequency is multiplied by 2, PN will be worse by 6 dB..



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    Re: mixer output phase noise and jitter

    Quote Originally Posted by BigBoss View Post
    If the frequency is multiplied by 2, PN will be worse by 6 dB..
    are you saying the jitter will double?



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    Re: mixer output phase noise and jitter

    The jitter will double....IF the two frequencies are correlated.

    If they are uncorrelated (i.e. two separate oscillators) the phase noise only goes up 3 dB, and jitter only goes up by √2.


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    Re: mixer output phase noise and jitter

    Quote Originally Posted by biff44 View Post
    The jitter will double....IF the two frequencies are correlated.

    If they are uncorrelated (i.e. two separate oscillators) the phase noise only goes up 3 dB, and jitter only goes up by √2.
    Hi biff44,
    thanks for your reply!
    i agree that phase noise goes up by 3 dB. But when we convert from phase noise to jitter, we have to divide phase noise by 2*pi*fc. So phase noise goes up by 3dB, but center frequency also go up 2 times.



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