Feeding TEM Horn Antenna with Coaxial Cable

feeding a tem horn antenna coaxial line

Hi All,

How do you feed a tem horn antenna with a coaxial cable.
How do I connect the outer and inner conductors and to which plate.
I'm trying to draw this in HFSS.
Please provide a rough sketch on this.

regards,
newbie101

tem horn design

You can simply connect the coax shield to one plate and the center pin to the other plate. Then assign a wave port on end of the coax line. Or you can use a lumped gap source in HFSS by drawing a rectangle between the two plates. Then you would need to assign it the impedance value.

Keep in mind that since the TEM horn is a balanced antenna and coaxial line is unbalanced, a balun is required to keep currents from traveling back down the coax shield. You may want to get a copy of the paper below, which has a balun design which converts from the coax line to the TEM horn parallel-plate input.

Design of an Ultrawide-Band TEM Horn Antenna With a Microstrip-Type Balun. Kyungho Chung, Sungho Pyun, and Jaehoon Choi.

Good luck.

Added after 18 minutes:

A wideband balun for the TEM horn antenna is described in this document. See Figure 4.30 for the HFSS model.

https://feldberyl.tripod.com/files/thesis.pdf