Question about 3-port SAW filter S parameter measurement...

I am a RF fresh man.
Now I'd like to measure a 3-port banlanced input and unbanlanced output SAW FILTER S parameter (for example: SAWTEK 856113) but I only have a two port Network Analyser,how should I do to get the S parameter? the third port's match is the key ?

1.measure the SAW use VNA 3 times ,and get 3 ports s parameters, convert it into differential-mode s paramenters with matlab
2.get a balun and match it to the balanced port of SAW

use a matched load to connect to one of the port
then use a NA to measure the two port S-parameters. Repeat this steps 2 more times.
You can get 3ports S-parameters.

http://web.doe.carleton.ca/~nagui/Ap...988-5634EN.pdf

Use 3 ports VNA, you can get the differential-mode s paramenters directly

You have to use matched load. I think the measurement should be pretty similar with 3 ports.

What is difference between the single ended and differential S paramenter ?

you can find differential-mode and common-mode directly in the differential s parameter