Analysis of transmission line periodically loaded with modulated loads

The paper presents the analysis of a periodically loaded transmission line (TL) excited by an aperiodic, localized source. Assuming that the loads are constant, a closed-form expression for the Green´s function of that structure was derived. In this work, the analysis of a transmission line loaded with periodic loads having modulated values is presented. The solution of the dispersion relation in this case is rather sophisticated compared to the case of constant loads. The plots of the propagation constant with frequency demonstrate the behavior of the structure in the passbands and the stopbands or bandgaps. The analysis of this structure opens different dimensions in the study and understanding of periodic structures as well as in engineering the bandgaps of such structures.