SuBill
Junior Member level 3
Dear all,
I know this is a very basic issue, but I'm new to ADS and I'd like to make sure my understanding is correct. Below is my schematic in ADS. I'm using S-parameter simulation. I got the values of S11, Z11, Zin in complex number format. I got confused about these terms:
1/ Zin and Z11, which is the input impedance of the circuit (hereafter mentioned as "ZLoad"), meaning the impedance looking towards the structure (including C1,C2,D1 and Term2) from Term 1?
2/ When I tried to calculate ZLoad from S11 using this equation:
Zload = Z0 * (1+S11)/(1-S11)
The result was totally different than Zin or Z11! So what kind of impedance the equation will give?
3/ I found an instruction here: https://www.edaboard.com/showthread.php?t=269785.
- For the first method, I'm wondering whether he's talking about this equation:
where Zin is my ZLoad, and ZL is the impedance of the circuit only, exclusive of Term2?
- For the second method (Smith chart) I really do not understand what he was talking about. How can I move towards load from Z11 if I do not know its value??
- At the same time, there is no transmission line in my circuit, which means transmission loss is assumed to be 0. So if I want to follow the above instruction, I have to add a pair of transmission line between Term 1 and the structure?
I hope anyone can help me to make clear these issues. Thank you so much and look forward to any response.
I know this is a very basic issue, but I'm new to ADS and I'd like to make sure my understanding is correct. Below is my schematic in ADS. I'm using S-parameter simulation. I got the values of S11, Z11, Zin in complex number format. I got confused about these terms:
1/ Zin and Z11, which is the input impedance of the circuit (hereafter mentioned as "ZLoad"), meaning the impedance looking towards the structure (including C1,C2,D1 and Term2) from Term 1?
2/ When I tried to calculate ZLoad from S11 using this equation:
Zload = Z0 * (1+S11)/(1-S11)
The result was totally different than Zin or Z11! So what kind of impedance the equation will give?
3/ I found an instruction here: https://www.edaboard.com/showthread.php?t=269785.
- For the first method, I'm wondering whether he's talking about this equation:
where Zin is my ZLoad, and ZL is the impedance of the circuit only, exclusive of Term2?
- For the second method (Smith chart) I really do not understand what he was talking about. How can I move towards load from Z11 if I do not know its value??
- At the same time, there is no transmission line in my circuit, which means transmission loss is assumed to be 0. So if I want to follow the above instruction, I have to add a pair of transmission line between Term 1 and the structure?
I hope anyone can help me to make clear these issues. Thank you so much and look forward to any response.