Basis of Spectral Analysis

The characteristics of chaos are of noise background and a wide spike in the power spectrum. Estimation of the spectrum, including estimating the strength of the EMI of converters via measuring the system harmonics distribution and studying the nonlinear behavior of converters via spectral analysis, is useful. In order to deal with spectrum in a proper scientific manner, in this chapter we return to the main theme of spectral analysis. We discuss this topic with Fourier transform following the concept of power spectral density (PSD), and introduce the classic and modern PSD estimation methods.