You can read the R&S application note
1EZ53: Measuring Balanced Components with Vector Network Analyzer ZVB http://www2.rohde-schwarz.com/en/produc ... |-904.html
More important one is you must define the correct differential impedance in the port configuration of VNA.
My question is pratically the same.
I would like to measure a differential Low-Pass filter with a VNA.
I have seen some subjects with S parameters transformations or something like that but i have not found procedures on how use the VNA for this measures.
Does anyone have an idea ?