If you want to simulate the antenna operating in a realistic environment with a surrounding box of water, you can set up the following structure:
1. Antenna structure placed inside a box of water (dielectric material defined as water).
2. Radiation box surrounding the antenna and the box of water.
This setup allows you to analyze the interaction between the antenna, the water box, and the radiation box, providing a more accurate representation of the antenna performance in a water environment.
If you are only interested in analyzing the antenna's radiation characteristics when exposed to a water environment, you can set for comparison:
1. Antenna structure without a box of water.
2. Radiation box surrounding the antenna with the dielectric material defined as water.
This configuration shows how the antenna radiates in the presence of water, without considering the effects of the water box itself.