Noise Power Spectral Density describes the noise spectral content in a 1Hz bandwidth, or simply the spectrum of the noise.
The noise power spectral density describes how the power of a noise is distributed with frequency.
The instantaneous power is then given by: P=S(t)^2
The noise power spectral density describes how the power of a noise is distributed with frequency.
The instantaneous power is then given by: P=S(t)^2
Using Wiener–Khinchin theorem, the PSD is the Fourier transform of the autocorrelation function, R(τ), of the signal: S(f) = ∫R(τ)e^(-2Ωifτ)dτ
