# Smith Chart and Maximum Power Transfer

1. Apr 1, 2010

### Bizkit

1. The problem statement, all variables and given/known data
You can find the problem http://whites.sdsmt.edu/classes/ee382/homework/382Homework9.pdf" [Broken]. It is problem 9.2.

2. Relevant equations
Zin = Zs* (maximum power)

3. The attempt at a solution
I've already figured out the first part of this problem. I plotted the normalized impedances at both the input and load (using the fact that Zin = Zs*), then found the distance between them (going counterclockwise) to be about .3482 wavelengths.

I'm a little confused on the next part. The way I see it is that you can't always choose such a length for maximum power transfer to any load impedance because not all normalized load impedances lie on the same constant VSWR circle as the normalized input impedance. Is this correct?

For the last part, I know that you can always choose such a length to get a purely real input impedance. As long as the normalized input impedance is located on the horizontal axis, it will be purely real. I am a little confused, however, as to how it will affect the maximum power transfer. I believe that if the input impedance is purely real, the amount of power delivered to the load will either be the lowest or highest amount possible. Is this correct?

Last edited by a moderator: May 4, 2017