SNR, dynamic range, which tone stand for noise?

Hi, All:

I did a FFT for my data, and plot them in Matlab,

I have one major tone(highest), and much noise tones(lower), if I want
to know the S/N ratio (dynamic range?) in this figure directly, what
should I do?

Which tone of noise should I take into calculation?

Thanks!

Boki.

 

You need to find the RMS noise, by squaring each
of the individual noise components,
adding all together, and taking the square root.
Then divide this into the signal component to
get S/N ratio.




Bob Masta
dqatechATdaqartaDOTcom

D A Q A R T A
Data AcQuisition And Real-Time Analysis
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