The Basics of Transmission Line Theory in Four Arrows [Educator’s Corner]

Transmission line (TL) theory can be considered a simplified and consistent framework within general electromagnetic theory, so the governing equations of the line and their solutions can be viewed as more tractable and understandable versions of their corresponding electromagnetic counterparts <xref ref-type="bibr" rid="ref1">[1]</xref>. This is particularly appealing for undergraduate students in electrical engineering since the vector nature of the field vanishes, and the propagation phenomenon in the line can be understood in terms of forward and backward scalar voltage waves. The presentation of the Smith chart <xref ref-type="bibr" rid="ref2">[2]</xref>, <xref ref-type="bibr" rid="ref3">[3]</xref> within this context gives a boost to this initial attraction since the chart beautifully replaces all complex calculations involved in TL analysis with mere geometrical considerations.