All Questions
Tagged with impedance-matching s-parameters
15
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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 ...
- 675
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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 ...
- 141
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How to create schematic of common mode choke that reflect on Common mode, differential mode and mixed mode? [closed]
I aim to create a schematic that can replicate the results exactly as seen in the measured S4P file. I have conducted the measurement using a VNA and am attempting the schematic simulation in CST. ...
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Challenges in Bandwidth in Common mode Choke Modeling
I'm currently working on characterizing a common mode choke (CMC). However, I'm encountering difficulties aligning the bandwidth of my model with the measured results. Specifically, when I attempt to ...
- 101
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Matching network for two-port with internally matched inputs/outputs
Background
I had a lab in school where we were given an LNA with inputs/outputs matched to 50Ω, that will be connected to a 50Ω system:
The task was to design the input and output matching networks:
...
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191
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How do you chain 2-port S-parameters onto a 1-port S-parameter?
With 2-port S-parameters, you can build up a circuit by chaining them together using ABCD or T-parameters, simply multiply the matrices:
We have measured a complex single port S-parameter of an ...
- 2,190
1
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answer
444
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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 ...
- 2,190
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3
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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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3
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Bad Reflection from SMA Board Connector at 4-8 GHz
recently I have tried to design a simple SMA-to-microstrip connector PCB intended for 4-8 GHz. The connectors used are vertical with surface-mounted centerpin (link).
The design idea was to simulate ...
- 123
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212
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Causes for negative port resistance of passive device (or obtaining |S11|>0 from measurements)
Suppose you have two reciprocal (passive) devices, A and B, both described with S-parameters \$S_a\$ and \$S_b\$. With a VNA, you measure \$S_a\$ and \$S_{\rm tot}\$ (S-parameters of AB, both devices ...
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Deriving the S-parameters, different Matched Loads possible?
I guess this is more of a conceptual question but for the problem below Im having trouble getting started on how to derive the S parameters for the network.
I noticed that the network at 28.025 GHz ...
- 1
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1
answer
349
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Coupling coefficient of microstrip resonators
I am working in HFSS and I'm trying to determine the coupling coefficient between two microstrip resonators (k) so that I can design a filter using a certain resonator shape. I have the formula I need....
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644
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Question on matched 3dB attenuator
For the second picture below, how to derive the expression for Vo?
I suppose there is some inbetween maths that I missed.
Note: 41.44 Ω is the parallel equivalent for (50 Ω + 8.56 Ω) || 141.8 Ω.
- 535
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Z parameters to Input and Output Impedance Conversion Question
I have to design a matching network for BGA7027 at approximately 870 MHz. My understanding goes that I should convert the S-parameters given in the datasheet to Z-parameters, from which I find Zin and ...
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2
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468
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calibrating vector network analyzer with \$75\Omega \$ coax
I am new to electronics and I just began to use a vector notwork analyzer for some measurements.
I calibrated my vector network analyzer with both ports connected to 50\$ \Omega \$ coax cables with ...
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