Hello. I missed the class where we discussed S-Parameters and I need help with t

Question

Hello. I missed the class where we discussed S-Parameters and I need help with these questions. If you could please explain while answering, that would be fantastic.
They don't cover this in my textbook and most of the things I find online aren't really helping me.

(The question has four parts)

Question: Find the S-parameter matrix for the networks

Figure 1: http://i33.tinypic.com/2qtftj6.jpg

Figure 2: http://i38.tinypic.com/15g8f2g.jpg

Figure 3: http://i33.tinypic.com/2vjxtnb.jpg

Figure 4: http://i35.tinypic.com/2zspiyo.jpg

Explanation / Answer

in a 2 port circuit S- parameters have the following descriptions :

S11 is the input port voltage reflection coefficient = (Zeff - Zo)/(Zeff + Zo)

S12 is the reverse voltage gain

S21 is the forward voltage gain

S22 is the output port voltage reflection coefficient

also b1 = s11 a1 + s12 a2

1) the circuit is shorted so b1 =0 and b2 = 0 all S11 = -1 S22 =1 rest zero

2) the circuit consist of an ideal transmission line of length lambda/4

so s12 and s21 will be exp(-lamda/4 * gamma) where gamma is the complex propagation constant

3) it is an ideal isolator where S21 = 1 and all rest are zero

4) open circuit hence S11 = 1 S12 =0 S21 =0 S22 =-1

Related Questions

Navigate

• Browse (All)
• Browse H
• Subjects

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.