Module 2 : Transmission Lines
Lecture 10 : Transmisssion Line Calculations Using Smith Chart
(C) Calculation of Transformed Impedance at a Distance from the Load
Suppose we have to obtain the transformed impedance at a distance from the load. Carry out the steps in (a) and (b ) to get to point Q. Now instead of measuring reflection coefficient, identify the constant resistance and the constant reactance circles passing through Q. They provide the transformed normalized resistance and reactance and respectively. Multiplying by we get the transformed impedance .
   
The same procedure is used for transforming impedance from any point on the line to any other point.
However if the distance `' is away from the generator, it should be treated negative and hence the rotation of the radius vector must be by in the anticlockwise direction.
   
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