Week 9: The End of Part One - Simulations

Hello!

I’ve been busy since the last blog was posted and have completed my senior project! However, there are still two blogs left after this, so in this blog I will talk about my SWR and radiation pattern simulations, and in the next two, I will talk about my measured results and engineering problems, respectively.

There is a software called MMANA-GALBasic that’s used to model radiation patterns, peak gains, and SWR based on the shape of antenna inputed into said software. Specifically, you start off with an empty XYZ coordinate plane and must use linear ‘wires’ to model any antenna you desire to create. Below is a screenshot of the input system:

For my helical antenna made of 8-gauge copper wire, I used 100 wires of the same length, but starting and stopping at different coordinates on the 3D plane, to model my helical antenna (7 turns, 12 degree pitch angle, 0.087m diameter). Then, I include a voltage source and a small inductive load at the beginning of my first wire which represent my NanoVNA. The resulting structure is what you see below:

After creating the structure in the software, I run calculations on it to reveal the simulated radiation pattern and SWR of the antenna. My simulations for this 8-gauge helical antenna are below:

Pay attention to the “Ga = 10.4 dBi” and “Gmax – Ga = 0.0 dBi” notations on the top center of the first screenshot. These are the gain numbers. Since Gmax – Ga is equal to zero, the top point (where the red dot is located) is the peak gain of the antenna, and at that point, said peak gain is 10.4 dBi. This software also says that the SWR of the antenna is equal to 2.8, but in real testing this number was lower, which will be explained later.

These were the simulations for only the 8-Gauge helical antenna, but simulations were also done on the 12-gauge helical antenna as well as the 8 and 12-gauge dipole antennas. They are all below, starting with the 12-gauge helical antenna:

8-Gauge Dipole Antenna:

12-Gauge Dipole Antenna:

See you soon!