I have introduced the Spatial Connector block after Polarization Rotator having Rotation Angle= 90 deg. The Spatial Connector has 90 deg Y tilt (to polarize the signal in Y direction) and after the MUX, I can see the two signals on the OSA polarized in X and Y. After the Parabolic-Index MMF, the signal power is dropped down to zero although the length and attenuation values of the MMF is negligible.
If, however, I take out the Spatial Connector block then everything works fine.
I do not understand the role of Spatial Connector here as I would expect it to just rotate the polarization by 90 deg and it should not have effect on the signal power after the MMF.
Can you please elaborate if I am using this block correctly or if there is some other conceptual issue here?
Attached is my simulation file for your consideration.