Can someone eli5 the Myquist frequency and theorem for me please?

>>9069266
Nyquist*

>>9069266
>eli5 the Myquist frequency
what does that even mean

>>9069277
Eli5 = explain like I'm five

>>9069266

Given a signal with x Hz bandwidth, the Nyquist frequency must be 2x

>>9069301
Right but what is the significance of this

>>9069285
Hello, reddit.

>>9069314
If you sample the signal with a sampling rate < its Nyquist frequency, there will be aliasing/errors

>>9069317
Ohhh that's actually quite helpful, thank you. Is there a way to quantify this with a data set? Perhaps through a power spectral analysis or by using a periodogram?

>>9069321
>quantify this
what do you mean? quantify the amount of errors?

>>9069327
No, to quantify what the nyquist frequency is given a data set. Say I have a discrete time series sampled at 50 Hz, and I wanted to know if 50 Hz was appropriate for the sampled data (e.g. if it was above the nyquist frequency for the time series), how would I find the nyquist frequency for that data set?

>>9069338
Oh, yeah you should just find the highest frequency in that data set using spectral analysis/periodogram/etc.

>>9069349
They say that when you plot a periodogram, that you shouldn't plot more than the power if 2 that you're working with, does this have to do with the nyquist freq as well or is this unrelated?

>>9069359
I don't actually know

>>9069368
I think it has more to do with the fourier transform. The periodogram repeats itself after a while, and most often after 1/2 of the 2^n you used