CHAPTER 4 - Impedance Matching
190
Now if we overlap the two, we get the chart shown in Figure 4.4-13.
Figure 4.4-13 Impedance Coordinates (green) and Admittance Coordinates (red)
By using the chart shown in Figure 4.4-13 we are able to design a matching network by using both
parallel and series elements. As we add reactive elements in series we will move up or down a
constant resistance circle, depending on whether it is an inductor or a capacitor that we are adding.
If we add reactive elements in shunt, we will be moving up or down a constant conductance circle
depending on whether we are adding an inductor or a capacitor. This is shown in Figure 4.4-14.
Figure 4.4-14 Adding series and shunt components on the Smith chart
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Shunt C
Shunt L
Series C
Series L
Conquer Radio Frequency
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