Engineering How can I understand reflection coefficient for a certain circuit?

[genxium]

How can I understand "reflection coefficient" for a certain circuit?

Homework Statement

I'm a beginner in RF circuit, though I've learned something about low frequency oscillator design, some new concepts still confuse me a lot, like the "reflection coefficient".

I google it and found the definition of "reflection coefficient" on wiki,
http://en.wikipedia.org/wiki/Reflection_coefficient"
but the definition of it for a certain circuit (like the figure with Vs,Zs,ZL in wiki) is still quite confusing for me >_<

Any one can explain how Gamma=(ZL-Zs)/(ZL+Zs) represents the "ratio of the electric field strength of reflected wave to that of incident wave"?

Homework Equations

Gamma=E-/E+ , Gamma=(ZL-Zs)/(ZL+Zs)

The Attempt at a Solution

none by far, I'm a beginner just for a simple concept explanation...

 

[seang]

I won't give you the full explanation here, but I will try to point you in the right direction.

When I was in college, I first learned about reflection coefficient from 'Engineering Electromagnetics' by Inan and Inan. This text will give you a good description of reflection coeff. and related concepts, with respect to transmission lines.

I would say, learning about RC with respect to t-lines is a good idea. It is a good compromise between time spent, and understanding what it is. It gives you the idea that, when dealing with RF stuff, you need to be a bit more conscious of physical aspects of a circuit, than you do with low-freq. circuits. However, the t-line approach spares you the rigorous work required to understand the reflection coeff. from a pure-EM approach.

Remember, fundamentally, RC is pretty simple, although the math may get difficult. You have a EM wave incident on a boundary. What comes back? That's mostly it. Circuits, t-lines, etc, are just special cases of this very general def'n.