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Voltage variation along a linę

Wc look at thc way thc total voltagc V(z) varics along thc lossless linc. Wc havc from cquation 2.42, with y = j #

V(z) = Vfe-j/iz+ViC+j/iz(2.82)

where Vrand Vrarc complex numbcrs. As wc go along thc linc. we will havc in cquation 2.82 thc two tcrms moving in and out of phase. thc rcsultant voltagc magnitude

having thc form shown in Figurę 2.24.

Notę there are two maxima in each wave length. The maximum and minimum values of thc voltage magnitude.

Notę that the incident wave will always bc greater in magnitude than the reflected wave whenever the reflected wave comes from a passive termination, so that the last equation always produces a positive value.