On the Origin of 1/f Noise due to Generated Entropy

Noise measurements analysis in this paper is associated with degradation in materials. In particular, one type is called 1/f noise and is not fully understood. In the time domain, the signal has a random noise appearance. However, in the frequency domain, the spectrum goes as 1/f in intensity at low frequencies; noise issues, of course, occur at all frequencies. In reviewing the literature, we note that 1/f noise in particular seems to be strongly related to aspects in materials that can be interpreted in terms of aging degradation in materials (i.e. disorder). In this paper, some key aspects of 1/f noise found in the literature are described and discussed how these observations are related to generated entropy. We can conclude from the literature, that the 1/f noise region is of paramount importance to observing subtle aging degradation occurring in materials. A thermodynamic framework is then used to help interpret the entropy-noise view. A 1/f spectral region entropy model is provided. We suggest two types of analyses. Results help to provide a broader understanding of 1/f noise, identify the region of the spectrum related to the onset of degradation, and show how it can be used to do prognostics. Experiments are suggested to demonstrate how 1/f noise measurements can be used as a prognostic tool for reliability testing to identify and predict degradation over time