I did a simulation of an antenna and replicated the antenna in an experiment however the simulation is coming out to be roughly the opposite. From the experiment I was expecting this plot to spiral from 1420 to 650 clockwise, however it's counterclockwise.
I don't have a background in electrical engineering and I was wondering, what could flip the pattern like this? Could it be that my dielectric for the simulation isn't chosen correctly or could it be that the dimensions of the simulation are incorrect? Any help would be greatly appreciated!
EDIT: the measurement was done with a vector network analyzer connected to the antenna with a SMA connector cable on one port. It's a two port system but the other port has a 50 ohm terminator.