Spectral Monitoring of a Defect's Origin

The spectral analysis of random processes or the measurement of the value of spectral functions that are the frequency distribution of the energy characteristics of the process is the most important part of the statistical measurements. At first, spectral analysis was used for solving the problem of investigating the characteristics of deterministic processes in contrast to the analysis of the distribution functions and correlation analysis, which were formed directly as a type of statistical measurement. Spectral analysis became an independent branch only after the role of measurement theory of the probability characteristics of random processes as well as the need for apparatus analysis of random processes had increased.