FORBIDDEN REGIONS OF L-SECTION IMPEDANCE MATCHING NETWORKS ON META-SMITH CHARTS FOR CONJUGATELY CHARACTERISTIC-IMPEDANCE TRANSMISSION LINES

摘要

In this article, the ZY Meta-Smith chart (MSC) is applied to intuitively determine a forbidden region for all eight L-section matching networks associated with conjugately characteristic-impedance transmission lines (CCITLs) with nonnegative characteristic resistances (NNCRs), where a load impedance cannot be matched to a CCITL. Due to the fact that the ZY MSC for CCITLs with NNCRs depends on the argument phi of the characteristic impedances Z(0c)(-) of CCITLs (which can be negative, zero, or positive), three cases for each L-section matching network are considered to determine the effect of the argument phi on forbidden regions, resulting in a total of 24 cases for all L-section matching networks. It is found that the ZY MSC for CCITLs with NNCRs is indeed a useful graphical tool for enabling intuition for radio-frequency engineers with additional physical insight into impedance matching of L-section matching networks. (c) 2015 Wiley Periodicals, Inc. Microwave Opt Technol Lett 57:874-879, 2015