hfss driven modal driven terminal
This also puzzled me. I think the essential difference or emphasis between driven modal and driven terminal is using modal based S-matrix or terminal based S-matrix. As we know, for some structures, there is no easy task to define voltage or current, so we need modal based S-matrix. Then for such kind of structures, we need to use modal based S-matrix. For structures operating with TEM mode, we may use either solution type: driven terminal or driven modal. As a result, it can be inferred that, as for microstrip antenna, the simulation results from terminal and modal type are very close. While there is a bit larger difference between results from terminal and modal type for loop antenna, however, still can be neglected. And this inference has been verified by my simulation.