Crest Factor Minimization for Wide-bandwidth Multi-sine Signals with Non-flat Amplitude Spectra using Partial Modulation

Monitoring the behavior of adhesives using dielectric analysis is challenging due to additives and fast curing reactions. Based on previous work, using multi-sine signals, partial signal components are introduced to increase the number of monitored frequencies while at the same time reducing the crest factor. A small crest factor indicates a high-quality multi-sine signal, which stands for high information density. Previous problems include that many similar frequencies increase the crest factor. Integrating partial frequency components counteracts this. Further, the error resulting from DFT analysis decreases when using this modulation method. The construction of multi-sine waves designed for dielectric analysis usually leads to a significant error in DFT, which is why this result is particularly beneficial. Thus, more information can be obtained at the same time with higher accuracy. Due to the specific signal composition and the DFT algorithm, an upper limit in frequencies is observed.