Questions tagged [s-parameters]
Scattering parameters or S-parameters (the elements of a scattering matrix or S-matrix) describe the electrical behavior of linear electrical networks when undergoing various steady state stimuli by electrical signals.
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Mismatch between input return loss and output return loss
I have a filter, which shows a mismatch between input return loss (S11) and output return loss (S22). They are not equal at the frequency of interest, which is around 36 GHz.
Would this affect the ...
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Frequency domain S11 to time domain conversion
I measure the S parameters of a network and I would like to convert S11 to time domain to see the reflections vs. time.
To achieve this, I measure (complex) S11 and then calculate the IFFT using ...
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How to evaluate input impedance on HFSS
I have simulated a 3D structure in HFSS and the figure below shows the "schematic" of the structure: there is a two-ports network and two transmission lines connected with different ...
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How can I convert S-parameters between series and parallel?
We evaluate RF amplifiers using actual equipment and a simulator (ADS).
Since there are few types of inductance values for air-core coils that can be used in matching circuits over 100W, we make our ...
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Suspected resonance from an S11 measurement
I was performing some S11 measurement of an AC cable because I see some strange results when I connect it to a device.
The cable length is 0.381m.
The cable is sitting on a Reference ground plane, the ...
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Mixer RF-to-IF isolation
I'm having a mixer IC working in the frequency as below:
LO frequency: 4.9 GHz (generated by internal VCO)
Port1 RF: 2.5 GHz
Port2 IF: 2.4 GHz
I want to measure the RF-to-IF isolation (that means I ...
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S-matrix of a 3-port circular network
I have 3 sub-networks, which are described by ABCD matrices.
I connected them together to form a 3-port circular network, described as follows:
Port1 → ABCD1 → Port2
Port2 → ABCD2 → Port3
Port3 → ...
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S parameter for transformer
Transformer is a two port system, I try to use simulation tool to find the s parameters for transformer.
Here is my questions:
How to accurately measure the s parameters for S11,S12,S21,S22. I find ...
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Measurement of s11 of differential output antenna transmitter
Normally, when we look at the s11 parameters from the feed point of a single-ended antenna, we can easily see the s11 reflection coefficient, yes.
Now, the question I am wondering is this: I have a ...
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Stability analysis from S-Parameter / Y-Parameter
I have a netlist from which I have contained the S and Y-Parameters of my circuit. Now I need to analyse my circuit for passivity and stability. Normally, I would use the transfer function to do this. ...
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The Theoretical and simulated S parameters of a TXline
If we consider a simple TXline of length \$l\$ and characteristic impedance \$Z_1\$, theoretically, its S parameters are
$$
S_{11}=\frac{Z_1-Z_0}{Z_1+Z_0}
$$
$$
S_{21}=e^{-j\theta}
$$
$$
S_{11}=S_{22},...
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Derive S-Parameter Matrices for Interconnected Multi-Port Networks of Arbitrary Size
Question(s)
Is the math below correct?
If not, then what should be changed?
If you know of an authoritative reference for this derivation, then please post it in an answer, or in the comments.
...
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Unable to replicate Twisted IFA antenna S-parameter curve using ANSYS HFSS 15
I am attempting to replicate the S-parameter curve for an antenna design as described in the paper "Antenna Design and Analysis" with DOI: 10.1109/LAWP.2009.2015345 using ANSYS HFSS 15.
Here ...
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S-parameters of a matching network
I have the following matching network designed for \$\omega=2\pi\cdot 1GHz\$ and I want to calculate \$S_{11}\$ and \$S_{21}\$. The normal definitions/calculation setup for S11 that I use are in the ...
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S21 calculation
In this post
It mentioned that there's a factor 2 in S21 value.
But I'm still don't understand why there's a 2 in it.
My schematic is shown below.
Shouldn't S21 = Vout/Vgen?
My question is: where is ...
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