All Questions
Tagged with impedance-matching filter
29
questions
2
votes
1
answer
73
views
understanding the recommended impedance match for a SAW filter
I'm trying to understand the recommended impedance match for a TA0168A SAW filter input. The datasheet is https://www.rfmw.com/datasheets/taisaw/ta0168a%20_rev.2.0_.pdf
In my first circuit I'm trying ...
- 286
0
votes
1
answer
164
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Wideband Impedance Matching for Inductive Source/Load
I'm designing the frontend of a receiver and I want the output impedance to be 50Ω so that I can get as much power into the mixer. I tried placing a bandpass filter (image filter for 88-108MHz) in ...
0
votes
1
answer
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
3
votes
2
answers
73
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What happens if you use L or C components in RF filters above their resonant frequency?
We have been optimizing filters (BP, HP, LP) by dropping a set of .s2p files into Microwave Office and letting the optimizer choose what works "best", but I started to wonder if that was a ...
- 2,190
1
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0
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85
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How do you "calibrate" (?) a matching network to re-optimize an S11 match based on physical measurements from a VNA?
We made EDA simulations to match an LNA input and had good results on the simulation (including EM simulation!) --- but when we built the board in real life the S11 match went from -30dB to -7dB. Ouch....
- 2,190
0
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198
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Do there exist Touchstone/S2P/SnP files for capacitors and inductors in the public domain?
I'm writing a Touchstone Perl module for reading and transforming Touchstone files to different parameter (S, Y, Z, etc) and format (DB, MA, RI) types. (Touchstone is also known as .s2p files or s-...
- 2,190
1
vote
3
answers
2k
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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 ...
- 2,190
1
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1
answer
1k
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Can admittance (Y) be used to calculate reactance when L and C values are calculated from the Y12 and Y11 parameters like normal as X=XL-XC?
My original question sought to understand the relationship between S-parameters and reactance. In the process of trying to figure that out, this second question arose. The actual question is at the ...
- 2,190
2
votes
2
answers
144
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How can one value describe the impedance of a group of reactive components at all frequencies?
The author of the textbook containing this circuit states that the filter input and output impedance is given by:
Z = (L/C)^1/2
He then shows that by setting the source and load impedance to this ...
0
votes
1
answer
320
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How should I route the ground plane under a RF trace with a LC balun?
I'm designing a PCB with a ESP32-PICO-V3, with a RF output to a 50 Ohms U.FL (Micro-Coax) connector. The chip supports WiFi and Bluetooth in the frequency range 2.45 +/- 0.45 GHz.
Right now, I have a ...
- 31
0
votes
2
answers
772
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Matching network and filter design
I am designing matching network at 868MHz frequency. I have a source impedance of Z=15.27-j1.27. In order to match that with 50 Ohm, I implemented LC matching network (red color). After that in order ...
- 27
1
vote
2
answers
434
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How do you combine 3 existing band pass filters to make a triplexer with 50 Ohm ports?
I have designed 3 microstrip band pass filters that each have a good 50 ohm match at the target frequencies (2 m, 70cm and 13cm bands) and I want to combine them into a triplexer to split one signal ...
- 13
1
vote
1
answer
43
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Would joining pads of a pi-filter eliminate impedance changes from line to pad? Would it cause problems with alignment during reflow?
This is a 2 part question:
Would joining the pads, such as on the lower pi-filter pictured, cause any problems with alignment of the components during reflow soldering?
Would joining the pads result ...
- 543
2
votes
1
answer
646
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In practice, does the order of a series RLC-shunt circuit matter?
In simulation I'm finding that the image pictured below works well to optimize a complex impedance match. I know that Z = ZL + ZC + R, so in theory the order shouldn't matter---but in practice, with ...
- 2,190
0
votes
0
answers
35
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Power gain values at the microwave amplifier
I have generated graphs in AWR software for signal gains, G_A, G_max, G_P and G_T, respectively. The amplifier I am using is "HMC141". Unfortunately, the values that came out look like this:
...
