Timeline for aliasing folding phenomena in frequency domain matlab
Current License: CC BY-SA 4.0
7 events
| when toggle format | what | by | license | comment | |
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| Apr 4, 2020 at 20:05 | vote | accept | rocko445 | ||
| Apr 2, 2020 at 13:03 | history | edited | teeeeee | CC BY-SA 4.0 |
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| Apr 2, 2020 at 10:39 | comment | added | teeeeee | Try to gradually increase the frequency of $f_3$, start with $40\textrm{Hz}$, then $45\textrm{Hz}$, $50\textrm{Hz}$, etc. You will see that when you hit the Nyquist $52.5\textrm{Hz}$ and above then the peak will bounce back inside the band - this is the folding you were talking about. | |
| Apr 2, 2020 at 10:31 | comment | added | teeeeee | As I said, if your Nyquist is only $52.5\textrm{Hz}$, you can never recover the wave at frequency $70\textrm{Hz}$, because it is outside your Nyquist and so it is greater than the maximum value you have on your frequency axis. Like I said in the answer, I would try repeat the process for a much higher sample rate as well (so you get the harmonic correctly), and plot them on the same graph. | |
| Apr 2, 2020 at 10:23 | comment | added | rocko445 | Hello as you said when i put f1=10 f2=20 f3=70 i get an alised harmonics at 35Hz but my 70Hz hamonics dissapears. Why is that? and How can we predict the amplitude of the harmonics? Thanks | |
| Apr 2, 2020 at 10:08 | history | edited | teeeeee | CC BY-SA 4.0 |
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| Apr 2, 2020 at 9:58 | history | answered | teeeeee | CC BY-SA 4.0 |