Effect of a Relatively Small Non-Linear Capacitor in the Unit Cell of Transmission Line Model on Scattering Parameters and Propagation Constant

摘要

The theme of this paper is to analyze the effect of a non-linear capacitor in the unit cell of the conventional transmission line model on its complex propagation constant. This constant is used in determining the electromagnetic wave propagation through the transmission line medium. The capacitance of a non-linear capacitor changes with the applied voltage. This variation is obtained by considering a non-linear constitutive relation between the voltage across the capacitor and charge stored on it. The propagation constant is derived from the scattering parameters. After the analysis is carried out, it is observed that the relatively small non-linearity in the unit cell is not affecting the desired band of frequencies while it is giving one more band of frequencies for the propagation of electromagnetic waves. A comparison is made between the linear model and non-linear model to observe the effect of non-linearity on propagation constant. From analysis it is observed that the relatively small non-linearities can be used as dual-frequency band transmission line models.