Dear All,
I am working on NI- measurement system (NI-PXIe 1075 chassi). the chassi contains 5 receivers and one LO, all the receivers are shairing the same LO.
I got problem with this measurement system since May 2016.
when I do a measurement, the waveform I get is not right as I compare it with the scope. at the begining, I thought the problem is with the calibration but then I relised that the problem with the phase becasue the magnitude is right. by doing further investigation about the problem I relised that when I use two harmonics insted of three, the waveform became exactly as the scope but with three the waveform is totally wrong.
then I found that the phase is fluped by 180 (deg). I didn't know the reasone why but I could solve the problem by adding 180. Unfortunatly I still have problem with one receiver. I couldn't find a specific case for that receiver to solve the problem.
The question is, Is it possible to have receiver working well with Magnitude and gives wrong phase. In case like this, could any of you help me to solve this problem. I will be really appreciated your help.
Thank you
best regards
Thoalfukar