How to add array factor calculation in ANSYS HFSS?

The array factor calculation method is a powerful technique to approximate finite array patterns based on a single simulated antenna element.

To add the array factor calculation, you can go to the HFSS menu item > Radiation> Antenna Array> Antenna Array Setup. HFSS provides 2 options; 1) Custom Array Setup: where the user can import an array setup using a txt file or 2) Parametric Array Setup: where the user can define the array setup in this interface.

1) Parametric Array Setup

In this setup user can define center position of the array, the direction of the array, the layout type, design frequency, and size and spacing of the array based on physical dimensions or electrical length. In the Array Weight tab, user can select different aperture taper function and different scan conditions.

In this example, a linear array of 4 elements is defined with a spacing of 8.7 cm and uniform taper function for the broadside case.

After the array is defined, we can look at the farfield data and perform different analysis. Below we see the impact on the directivity. As seen, the directivity has increased by 6 dB (a factor of 4) as expected.

2) Custom Array Setup

The second approach to create the array setup is to import a txt file that contains; 1) number of element, position, amplitude, and phase. The text file must have the following format. Coordinate values are assumed to be model units, and phase and amplitude are in SI units (radians and volts respectively):
Nx
x_1 y_1 z_1 A_1 P_1
x_2 y_2 z_2 A_2 P_2
...
...
x_N y_N z_N A_N P_N
where
l x_1 is the x-coordinate position of the first element.
l y_1 is the y-coordinate position of the first element.
l z_1 is the y-coordinate position of the first element.
l A_1 is the amplitude weight of the first element. Amplitude references voltage.
l P_1 is the phase weight for the first element. Phase references radians.

Below is an example of linear array of 4 elements placed along the x-axis similar to the one defined using the "Parametric Array Setup";

4
0 0 0 1 0deg
8.7cm 0 0 1 0deg
17.4cm 0 0 1 0deg
26.1cm 0 0 1 0deg

To create the custom array setup, click on import definition and browse to the txt file. user can click on "View Definition" to view the file as seen below.