AnsweredAssumed Answered

Measuring S22 an S11 with 5242A

Question asked by keplovic on Apr 12, 2010
Latest reply on Apr 13, 2010 by keplovic

I'm measuring a Transsmisor/Receptor DUT and I want to Know the match of the DUT. I'm using a 30dBm power signal in port1 and port2 of the DUT.

I apply a Source power calibration in both ports, and a Full 2-ports S-parameters calibration.

In order to verify that the measured values are ok, i have made 2 differents measurements.

1- I have measured the S11 parameters:

  PNA Port1 --> DUT Port1    and    DUT Port2 --> PNA Port2


2- I have measured the S22 parameters:

PNA Port1 --> DUT Port2    and     DUT Port1 --> PNA Port2


Both measurements should be similars, but you can be in the picture below that the measurements are diferent.

Why can be so diferents? I don't understand the reason


Thanks very much