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S11 is one of the S-parameters. It uses 1 port on the VNA to look into something and look at the reflection coming back to determine reflection coefficient / VSWR. If the device was calibrated properly then it can also tell you the complex impedance of what it is "seeing". To calibrate you have to use open, short, and load (99% this is 50 ohm), but ...


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I think the problem you will run into is that people will want this to be plug and play. They may not have a directional coupler, or know or feel like to calibrate it and all that other stuff. Even if they do it, they may wonder if they did it right and if the reading will be accurate or not. I think you will need to handle this part in your design and ...


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Antenna efficiency over 130% would mean a perpetual motion machine, so probably not.


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Smith chart shows that 50 Ohm antenna (assumed perfect 50 Ohm real!) connected to 75 Ohm coax cable can result in impedances between 50 and 112.5 Ohm. SWR 1: 1.5. So this so far not mentioned possible solution in this thread may be usefull for your problem: for a single frequency, or for a small frequency band, the use of cable with a multiple of half ...


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Well, according to the spec tables in the manual the thing expects a 50 Ω antenna impedance. Mismatch means a loss of signal energy. How much exactly depends on the length of the 75 Ω transmission line – this makes a system much harder to design predictably. I wrote all the following (up to the next horizontal line), then stopped to wonder "what might ...


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