An efficient tool to study transmission lines using the wavelet packet decomposition

Wavelet expansions have received a lot of interest in the EMC literature. In fact they have been widely used in electromagnetics to expand electrical quantities either in time or space domain, allowing an adaptive representation of the solution. It has been shown that the discrete wavelet transform is just a particular case of the discrete wavelet packet transform. The paper deals with the comparison of the standard wavelet transform versus the wavelet packet transform in studying MTLs, pointing out the advantages in using the latter approach respect to the former one. In particular an appropriate choice of the wavelet packet basis is shown to be effective in reducing the computation time and memory storage requirements. Several validations and numerical examples are presented.