two ports in horn antenna?
One guy come to me asking if you can test the bandwidth of a conical horn antenna putting 2 ports, one as normally used in the entrance of energy and the another one at the aperture. I told him that it would be incorrect because the S parameter of the feeding port gives you the behavior as a filter, and also he would be forcing the fields at exit. You need one port and radiation on the otherside.
However, you can tell me if my assumtion is correct.
Regards and thank you:D.
Edgar.
You are correct. The horn couples into free space. Any additions to the far end of the horn will affect the transmission line port impedance.
This is assuming that your simulation program simulates physical reality. It may be the case that it has a point size port that measures voltage and current, but this would be at the radiating end and not the far field measurement.
two horns keeping face to face with one port as input at transmitter horn and second port at reciever horn at output can be the case.
Thak you both, your answers have been very useful.
In the case that "kecbackbencher" mentions, those two antennas must be placed face-to-face without any spacement between them, right?
yes.. no space between them for avoiding space losses