I was doing S-parameter simulation in cadence to find out the differential loss of a simple circuit. I know the simple formula for return loss Return Loss = (ZL-ZS)/(ZL+ZS).
For simple resistor circuits the hand calculation and the cadence simulation results are same. For the attached circuit I couldn't able to realize the capacitors and find the return loss. In the following circuit, cap value= 2pF and resistances are 50 Ohms each with 100 ohm Port across them.
I am getting a value of S11 = 299.717mV. But I couldn't get the same value through calculation. Please refer the attached image.
In cadence S11's magnitude is 299.717m , I assumed 1V(for understanding), so that I said it is 299.717mV. Anyway I correct this. This doesn't mean I should review my knowledge. Before commenting like this, you should understand what other person is trying to say. Watch your back, before commenting other's knowledge.
For the attached circuit I couldn't able to realize the capacitors and find the return loss.
In the following circuit, cap value= 2pF and resistances are 50 Ohms each with 100 ohm Port across them.
I am getting a value of S11 = 299.717mV.
But I couldn't get the same value through calculation.
I have gone through the attached threads. It is similar to this question but, in the attached snap there is only one port so S11 only available. And I assume this as return loss. In that case I assume Z0= 100 Ohms(Port Impedence).
so how to calculate Z1 so that i can substitute s11 = (Z0-Z1)/(Z0+Z1).
If there is no cap in the above circuit it is easy to say that Z1 = 50Ohm +50 Ohm = 100 Ohm and no loss. But now I have capacitance also. And I am sweeping frequency from 1Hz to 10GHz.
The S11 value at 1 GHz is 299.717m. Got my question?
. Can or cannot depends on myself only, So never say like this.
Coming to the point, We do this to measure the differential loss in my side and I know about the mode conversion and it needs more than 2 ports. In my design I have one port.. So simply I need to measure S11. I don't know whether it is differential.
So apart from saying "you dont know the basics...like these", try to understand what I am trying to measure from the attached circuit. and share your thoughts accordingly.
Thanks for the understanding.
Please Be polite on others. Everyone don't know everything. Thanks for understanding