AN-SOF: Empowering antenna simulation, modeling, and design.
AN-SOF: Empowering antenna simulation, modeling, and design.
Simulation of a multiband dipole for 3.7, 7.05, 14.2, 18.1, 21.2, and 28.5 MHz.
There are 6 dipoles of almost half a wavelength each. They are all connected to the same feed point.
This is an example where we need simulation software capable of modeling very close wires.
This small transmitting loop antenna is 1 meter high above average ground, so the radiation pattern is not donut-shaped as expected for a small loop in free space. The value of the tuning capacitor is indicated for each resonance frequency.
Large loop: 70 cm in diameter, RG-8 cable.
Small loop: 15 cm in diameter, RG-6 cable. Inductive coupling between the feedline and the large loop, spacing of 2 cm.
The color scale on the loops indicates the current flowing for a reference voltage of 1 V.
Download the project files from this link >.
Go to AN-SOF main menu > Run > Run Bulk Simulation and select the five “.nec” files to run the calculations automatically. You can do it with the trial version of AN-SOF.
This design is for 5 bands on a single pole. Each “J” corresponds to a band and therefore the feed point changes depending on the frequency. The resonance frequency is indicated in each case, which can be changed by moving the feed point. The height is about 5 m.
This model is self-resonant (50 Ohm) in the analyzed frequency range, so it does not need a matching network. Adjust the indicated gaps to minimize the VSWR.