What 'exactly' is power spectral density for discrete signal?
I was always under the assumption that taking the Fourier transform of the signal, and then the ratio of desired frequency range magnitude over the entire frequency range gives the power ratio for that frequency range which is the same as power spectral density. Is that wrong?
Reading a student paper got me confused as it says to compute PSD and then 'absolute and relative spectral powers in desired bands' as well. Are they different? If yes, how does one compute it?