Questions tagged [s-parameters]
The s-parameters tag has no usage guidance.
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Scattering matrix of quarter-wave transformer
I am trying to solve for the scattering parameters of a quarter wave transformer. The example that I am given is a transformer with characteristic impedance 100 Ohms, and the reference impedance (...
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Problem understanding lossless T-Junction divider
I am studying how the lossless T-Junction divider works. I am going to assume that the susceptance in the junction is 0 for simplicity, and it is not relevant to my question.
The structure of a T-...
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How do I calculate insertion loss for a dual input receiver?
Typically my test setup consists of:
Antenna->Antenna Feed Cable->switches->Filter->LNA->Spec An feed Cable->Spec An
I calibrate the cable loss by simply getting the S21 (S1 ...
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S parameters calculation from VNA file
I am trying to validate that our broadband LNA(Low noise amplifier) is working correctly. I wanted to measure the S21 of the LNA, I calibrated the VNA for the specified frequency range and measured ...
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Does insertion loss include return loss?
Does insertion loss include return loss? If we take a 3-ports circulator, does insertion loss from port 1 to port 2 consist of return loss of port 1, a power that leaks throug port 3 and power ...
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S-Parameters Re-normalization
When we talk about S parameters for a certain number of ports we typically reference each port to a specific impedance, most of the time to one common \$Z_0\$ impedance, but in general terms to a ...
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Help in understanding resonance in 1/4 wavelength detector / S parameters
So this might be long question that requires some literature review but I will try condense it as much as possible such that hopefully I can get some help without the reader having to review the ...
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How to add an S-model of a capacitor to HyperLynx simulation?
I am struggling with the problem described in the title. I have the s-model of a capacitor I incuded in my design (.s2p series model for a capacitor put at the output pins of an IC in an LVDS line). I ...
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S-Parameters Power Loss
I am trying to calculate the power loss in a 2-port system, via the s-parameters.
The actual system is a cavity with 2 waveguide ports and a dielectric mass. I know the power that is being pumped into ...
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Applying an electrical field to a particle in Ansys HFSS
Does Ansys HFSS have the ability to show the applied electrical field to a particle?
I designed a coplanar wave guide in this software, something like in this video.
Is it possible to put a particle ...
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Why is the extract() function returning the same data for different inputs in MATLAB?
For some very strange reason, the extract() function appears to be returning the original s-parameter data for the first object again and again!
It should return different data depending on the new ...
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Intuition for S-parameter formulas?
Wikipedia defines S-parameters as[1]:
$$
\boldsymbol{b} = \boldsymbol{Sa}
$$
Where:
$$
a_i = \frac{1}{2}k_i (V_i + Z_i I_i)
$$
$$
b_i = \frac{1}{2}k_i (V_i - Z_i^* I_i)
$$
Saying it is defined in [2], ...
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Rollett stability factor - derivation and numerical meaning
For two-port networks, a value called the Rollett stability factor, K, can be derived, whose value can then be used to assess one of the criteria for the network to be unconditionally stable (K > 1)...
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What is the difference between Smith charts plotting Z11 and S11?
Background
In the process of trying to fix an LNA input impedance match, we discovered we need to understand more about Smith charts! The question is the at the bottom of this post, here's some ...
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Question about two S parameter curves in ADS (Advance Design System) software
How do I subtract two S parameter curves and display the result? How do I do this for results from two different models in Advance Design System (ADS) software?
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The meaning between raw and calibrated S parameters
VNA: E5071C
Cal kit: 85033E
DUT: cable end bandpass filter
This figure shows measuring S21 of filter:
Upper figure shows real part of S21 and lower one shows imaginary part of S21.
Blue line is raw ...
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How vector network analyzer measures S-parameters of lumped element?
i've seen video lecture where S-parameters of 50 Ohm resistor placed in series between input and output port of VNA with reference resistance also of 50 Ohm are calculated by hand. S11 was calculated ...
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Passive component S-Parameter measurement: Difference between series and shunt
Johanson provides S-parameter measurements for their RF capacitors in touchstone file format (see here). Specifically, looking at the S-Series files, they provide series and shunt type measurements.
I ...
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S21 & S12 of a mismatched transmission line
I am trying to solve this problem:
Since it is asking for a reference impedance of 50 Ω there will be a mismatch, and hence reflections at the Port 1 for calculation of S12.
I already know S11 and ...
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Direct recovery of step response from S-parameters in near-end crosstalk case
The conversion of S-parameter data to impulse response/transfer functions is typically done by interpolating the S-parameters, resampling to a uniform grid, and applying an inverse FFT. This works ...
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Given S-Parameters (or Y,Z,T,ABCD), how can you calculate \$Q_C\$ and \$Q_L\$ (or, how do you calculate ESR)?
Background
I'm writing a .s2p/Touchstone library for Perl and I'm trying to get the Q value of a component given an S-parameter matrix.
The Goal
In this case I'm trying to get Q for a 10nF muRata ...
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S parameter model of the capacitor
For same capacitor, there is no s-parameter model, so can we use the model from other manufacturer of the same spec.
Eg:
Caps with model - C0603C104K5RACTU - KEMET - Cap, Cer-X7R, 0.1uF, 50V, 10%, ...
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Comparing scattering parameters in dB and magnitude+angle forms
We're trying to compare the scattering parameters from two parts (ADG902 and BF1101). Their datasheets use dB and mag/angle respectively.
ADG902:
BF1101:
When trying to convert between the two, we ...
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How to extract s2p file from a large-signal model? - ADS
I am working on a RF IC and I wish to extract s2p file from large-signal model (the large-signal model is available in producer company). How can I do that in ADS?
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How to modify s2p file of an IC? - ADS
I have a s2p file of a RF IC which it contains frequency from 650 MHz to 1.1 GHz. I wish to modify s2p model so that two frequency 0 Hz and about 3.5 MHz is added to the s2p file.
How can I do that ...
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What would be the S-parameters for an "ideal" shorted transmission line?
I seem to remember that the shorted- vs open-transmission line reflection is out of phase by 180-degrees. I'm new to the mathematics behind transmission line theory and I'm trying to figure out how ...
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Which matrix index should be used when Y (admittance) is shown to compose a circuit segment mapped to an ABCD matrix? Y21? Other?
I would like to cascade a serial capacitor with a shunt inductor to form an L-match network by multipling two ABCD parameters and convert the result to S-parameters that represent the composite ...
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What does \$\beta\$ represent with respect to the length of a transmission line?
The picture below shows the ABCD parameters for a transmission line of length \$l\$ from this video.
Question: What does \$\beta\$ represent?
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Are T-parameters the same thing as ABCD parameters?
S-parameters can be converted to either T-parameters or ABCD-parameters, and both are considered a "transfer matrix". The conversion from S-parameters to T- or ABCD-parameters are defined ...
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How are S-Parameters and Reactance related, can one be calculated from the other?
I know that, for example, \$X_L=2\pi f L\$ will calculate reactance of an ideal inductor, but can this be calculated for a real component model? Given the S-Parameter values at some frequency from an ...
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Converting measured S-parameter to Z-parameter does not match the Z-parameters measured on the same circuit
I have measured the S-parameters for a 4 port circuit. For a certain frequency those values are:
...
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Which capacitor equivalent circuit should I use in an AC PSPICE sim?
I am trying to simulate the frequency response of a buck converter with the specific ceramic caps that I will be using on my board. The goal is to evaluate stability (phase margin).
The OEM does not ...
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Voltage along transmission line with scattering parameters and VSWR given
A transmitter is connected to an antenna with a coaxial cable with length \$l=1.5 \:\text{m}\$. The characteristic impedance of the cable is \$Z_0 = 75 \: \Omega\$ and the scattering parameters are \$\...
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Common mode choke - Why only impedance?
Why are most common mode chokes only given with a impedance curve, inductance at a specific frequency and current rating (this is clear😅).
Wouldn't be S-parameter better? I know it's more work, but ...
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How to interpret S parameters on a Smith chart
I am trying to understand S parameters on RF transistors.
I chose the BFP840ESDH6327XTSA1 as my RF transistor, to operate it at 10 mA, 12GHz. The design should be optimal for simultaneously matching ...
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Two-port network parameter measurement using an LCR meter
I was wondering if it's possible to find the admittance parameters of a pi two-port network experimentally using an LCR meter.
For the network shown below, we have
$$
\begin{bmatrix}
I1\\
I2
\end{...
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Recommended Fixture for a 10 MHz to 40 GHz S-Parameter Collection
I would like to characterize a range of SMD and TH components in order to show how different components have different parasitic elements that must be accounted for as frequency increases. I would ...
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How to compute S21 when port 1 and port 2 reference impedance (Zo) are different
The attenuator given in the figure is a 6 dB attenuator when both port 1 and 2 have a reference impedance of 50 Ω.
Then, their S-parameter matrix (when port 1 and 2 have 50 Ω reference impedance) ...
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Passivity and Causality of PCB channel
We use S parameters to analyze a PCB channel. Once the S parameters are extracted, what I have seen is SI engineers will check the S parameters obtained are passive and casual.
I have some questions ...
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Combining S-parametric Blocks
I would like to ask you, please, how I can combine general S-parametric blocks together. Consider the situation in the following picture.
Considering this example, I would like to connect these three ...
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Calculating the real power consumed in a two-port network using its S-parameters
I would like to express the real power consumed in a two-port network using its S-parameters.
Assume for simplicity \$\underline{Z}=R\in\Re\$
(1) My idea was using energy conservation:
$$ P_{in} = P_{...
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Why do we use S parameters for channel modelling, rather then using Z, Y, h or any other parameter?
For channel modelling in high speed PCBs we always use S parameters.
What is the specialty of S parameters for this purpose?
Why we are not using Z, Y, h or any other parameter?
How do we determine ...
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Can port parameters in one representation (mag-angle, decibel-angle, or real-imaginary) be converted to the other?
I'm trying to figure out what network parameter data would be "best" to use when generating a Touchstone file, or if the different data representations are equivalent in terms of the ...
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S Parameters Channel Modelling Time domain representation of insertion loss
Below is the insertion loss waveform obtained after S parameter of a channel.The waveform is in frequency domain.
May I know what is the equivalent time domain waveform and how to obtain it from this ...
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How to interpret VNA data?
I'm looking at the raw data from a VNA (HP 8720A) and I want to understand how to interpret it, and how to do after-the-fact calibration (ie: read raw data, then apply to it whatever corrections a ...
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What is the significance of a negative imaginary component in a S21 measurement?
What is the significance of a negative imaginary component in a S21 measurement ?
For example, in the following plot of a passive network, the linear magnitude of the S21 parameter decreases with ...
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De-embedding ceramic filters
I want to design a diplexer using two ceramic filters.
S2P files of the filters are not provided. Therefore, I designed a PCB which can be shown below to obtain their S2P parameters.
In the first ...
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Differential Pair Mode Conversion [closed]
What is the purpose of using these mode conversions?
SCD
Input: Differential
Output: Common
SDC
Input: Common
Output: Differential
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Are multiple reflections accounted for in S-parameters?
When the S-parameters of a 2-port device whose input and output impedance are different from 50 Ohm are calculated/measured in a 50-Ohm system, multiple reflections occur at port 1 and port 2.
Let's ...
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How to find Z impedance if I have only S11 (db) and phase
I need to measure Z line impedance. Using VNA I measured S11 it is -53.8785 dB and phase at this point is 175.6706.
Could you explain using these numbers how to find R and jR
S11 = (Zx-Z0)/(Zx+z0) = -...
