What is the units of FFT, when doing Spectral Analysis of a Signal?
For above question, the answer could be V or V/HZ for voltage signal. Which one is right? I would expect the result to be V.t or V/Hz because of dt.
I used the
pspectrum
function in MATLAB to create a spectrogram image with power spectrum and dB magnitude.
In general, the spectrogram is obtained as the square of the absolute value of the Short Time Fourier Transform. Also, the power spectral density of a normal signal is studied as |FFT|^2. Then since it is a density function, does the integral value by applying the window function to the frequency domain of |FFT|^2 express the power of the signal in dB? I have seen different interpretations of power spectrum and power spectral density. Parseval's theorem also means that the energy in the frequency domain and the time domain could be the same. If the dB scale power spectrum is integrated by multiplying |fft|^2 by the window function, is this also a power spectrum?