Hi, I tried sampling [tex](adsbygoogle = window.adsbygoogle || []).push({});

s(t)=sin(400\pi t) + 0.5cos(12000\pi t)

[/tex] at 10000Hz (below the Nyquist sampling rate)

in matlab and plotted the spectrum, I found that it had frequencies at +-200Hz (same as the continous signal version) and +- 4000Hz(instead of 6000Hz in the continous signal).

Just wondering how sampling actually affects the spectrum of the signal, is there a formula or something which can tell you the frequency components based on the sampling rate?

Thanks for your help,

frenzal

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# How does Sampling affect a Spectrum?

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