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smwk Junior Member Offline Posts: 25 Pakistan	Testing matching circuit on VNA Jan 27^th, 2014, 10:02am I have made a matching circuit by matching (50) ohm to (0.89-j2.3). Now I want to test the matching circuit fabricated on microstripline on VNA. The problem for me is how to give a load (0.89-j2.3) on the VNA port to test the circuit and verify the practical results.
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RFICDUDE

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Re: Testing matching circuit on VNA
Reply #1 - Jan 27^th, 2014, 5:14pm

It is not common to attempt to program the VNA to imitate a specific load impedance.

The VNA is typically used to measure the s-parameter response of a component. The s-parameters are generic in that they can be used in simulations where the port impedance is not the same as the VNA used during the s-parameter measurement. Therefore in the simulator you can use the measured s-parameters and put your 0.89-j*2.3 ohm load on one end and measure the impedance at the other end to verify the match is correct.

I hope that this is helpful to you.

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smwk

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Re: Testing matching circuit on VNA
Reply #2 - Jan 27^th, 2014, 10:50pm

Thanx RFICDUDE ...
My concern is testing on VNA
I have already simulated the circuit in ADS where i m getting good match i.e. getting S11 equal to -28 dB. But after making the matching circuit practically I want to test it on VNA inorder to see the difference between the simulated result and practical result. On VNA i can give 50 ohm on one port but cant give (0.89-j*2.3) on second port . So how to measure the practical result?
hope u got my point...

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aaron_do Senior Fellow Offline Posts: 1398	Re: Testing matching circuit on VNA Reply #3 - Jan 28^th, 2014, 4:49pm Hi smwk, he got your point. What he said was: Just measure your matching network with a 50-ohm load. You will get a set of two-port s-parameters. You can then use those s-parameters that you measured in a simulation with whatever load you want. regards, Aaron
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smwk Junior Member Offline Posts: 25 Pakistan	Re: Testing matching circuit on VNA Reply #4 - Jan 28^th, 2014, 11:57pm Thanx aaron..and RFICDUDE as well. Now I got your point. Actually you explained it in simple words. Thanx
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