SMT Power Spectrum to IQ Data

I have a 20 MHz IF Signal.
I used SMT Basic Zoom Power Spectrum to zoom in
and capture 5 MHz of that Spectrum.
Can I get back IQ data corresponding to this Zoomed 5 MHz Spectrum.
I tried using IFFT to get back IQ data  from the Spectrum,
but the results are not correct
Which VI should I use to convert Power Spectrum to IQ Data. ?

Hi Walban,
I would like to ask for clarification about what you are
looking to do. I understand that you have an inverse FFT, but can you expand on
the definition of ‘different distributions’ ? I am puzzled by how we can have
different data, but the same spectrum. Lastly, what version of LabVIEW are you
using? Are you using the Spectral Measurement Toolkit (SMT)? This knowledgebase: How Do I Use the FFT and Inverse
FFT VIs in LabVIEW? (http://digital.ni.com/public.nsf/allkb/549BCD6B247012F686256E00002509E5?OpenDocument)
may help with using the FFT and Inverse FFT functions in LabVIEW.
David L.
Systems Engineering
National Instruments

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    Attachments:
    Power Spectrum.vi ‏19 KB

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    Systems Engineering
    National Instruments

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    Attachments:
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    Condition Monitoring Systems
    Vibration Analyst III - www.vibinst.org, www.mobiusinstitute.com
    National Instruments
    [email protected]
    www.ni.com/mcm
    www.ni.com/soundandvibration
    www.ni.com/biganalogdata
    512-683-5444

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    Attachments:
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    ReadXYZmine.vi ‏18 KB

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    Attachments:
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    I am looking to accelerate the performance of the Power Spectrum and
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    Hi,
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    Hi,
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    Attachments:
    wiring.GIF ‏9 KB

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    Attachments:
    acquire time domain signals.JPG ‏46 KB

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    Attachments:
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    Attachments:
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