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Why maximum value of STFT becomes 0.2 times of window length?

Hello there,

 

I am using below TFA STFT.vi in my program.

STFT.png

 

Although there is also TFA STFT spectrogram.vi, I don't use it because I don't get the full meaning of reassigned? boolean.

 

When I tried to check the value of STFT by below example, I felt some strangeness because of the maximum value of spectrogram.

Because I inserted RMS 1 Volt signal as input signal, I expected that the maximum value of spectrogram is 1.

However, it is 0.2 times of window length.

If we are using MATLAB, it is needed to divide by nfft when we try to determine power spectrum.

Is this same procedure? If it is, what number is the specific value for doing this?

STFT_frontPanel.PNGSTFT_blockDiagram.PNG

 

 

Thank you for reading this.

 

Sincerely,

Albert

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Not to 0.2 times of window length

 

divided by 3 of window length..

 

For example, window length : 30,720  and  the maximum value of spectrogram : 10,240

 

 

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