An extended ZY T-chart for conjugately characteristic-impedance transmission lines with active characteristic impedances

Abstract

It has been shown recently in the literature that the conjugately characteristic-impedance transmission lines (CCITLs) implemented by periodically loaded lossless lines can exhibit active characteristic impedances (i.e., negative characteristic resistances). In this case, the magnitude of the voltage reflection coefficient is always greater than or equal to unity for passive load termination. Because of this reason, some modifications to the standard T-chart, a graphical tool for solving CCTTL problems, is necessary. The modified chart is called as an extended ZY T-chart, where the range of plotting is always outside or on the unit circle of the voltage reflection coefficient Γ plane. It is found that the extended chart depends on the angle Φ, the argument of the CCITL characteristic impedances, in a complicated fashion. © 2007 Wiley Periodicals, Inc.