Hi All.

I need to build a Pi Network for my circuit as shown in the fig below.



So I have a 'Pi Matching Network' in my circuit. The datasheet asked me to build a Pi Matching Network. ( You know, how there is a series component, a source shunt component and a Load shunt component. )

Anyway, my VNA keeps telling me this: The measured load impedance is 31.9-58.5j.

The VNA is automatically generating these four groups below ( group 1 thru 4 ) of available matching parameters on the screen:

1. 5.24pF capacitor for source shunt and 28.8nH inductor in series.
Does that mean, this group does not need a Load Shunt at all? Does this mean that the proper tuning has been achieved with just a capacitor for source shunt and an inductor in series?

2. 23.1nH inductor for source shunt and 12nH inductor in series.
Does that mean, this group does not need a Load Shunt at all? Does this mean that the proper tuning has been achieved with just a inductor for source shunt and an inductor in series?

3. 97.5nH inductor for load shunt and 23.3nH inductor in series.
Does that mean, this group does not need a Source Shunt at all? Does this mean that the proper tuning has been achieved with just a inductor for load shunt and an inductor in series?

4. 15.3nH inductor for load shunt and 5.21pF capacitor in series.
Does that mean, this group does not need a Source Shunt at all? Does this mean that the proper tuning has been achieved with just a inductor for load shunt and a capacitor in series?

If the answer is yes to all the 4 above questions, then I still cant believe that a 'Pi matching Network' can exist with 1 of the 3 components totally missing.

Ty for your reply!

 

To understand VNA given values and what appears to be missing components would require more than a simple yes or no.
A step by step approach with the VNA and your 50Ω fixture explained in a format that works for you.
There are techniques procedures and specifications that give different results. The methods can be specialized and very precise.
There are numerous sites with good explanations and related content. Finding quality training that meets ECE and VNA today is large order.

https://ez.analog.com/ez-blogs/b/engineerzone-spotlight/posts/the-top-5-things-you-need-to-know-about-rf-matching-networks#:~:text=In RF circuits, the impedance can vary over

 

If the answer is yes to all the 4 above questions, then I still cant believe that a 'Pi matching Network' can exist with 1 of the 3 components totally missing.

If you get rid of one of the shunt components it is not a PI-match anymore but a L-match. On a PCB, in case you don't know the exact impedance of the load (e.g. antenna) yet, you would normally make room for the full PI matching network but populate only two of the components as needed. L-matches realized only with inductors are not seen very often because inductors are usually more expensive and have higher loss than capacitors. Vertical antennas that use a tapped air coil at the base employ this kind of two inductor L-matching technique. In most cases an inductor/ capacitor combination is used, either in a lowpass or highpass configuration. PI matching networks have one advantage over L-matches, you have control over the bandwidth (Q-factor) of the network.