Uniform Aperture Circular Antenna

Uniformly illuminated circular aperture antenna.

This antenna uses a polar coordinate system.

Parameter	Description
Beamwidth	The beamwidth of the antenna gain pattern. Valid if Use Beamwidth is selected. The diameter and gain are automatically calculated on the basis of this value and the frequency.
Diameter	Diameter of the dish. Valid if Use Diameter is selected. The beamwidth and gain are automatically calculated on the basis of this value and the frequency.
Design Frequency	This read-only field displays the frequency inherited from the antenna's parent object (receiver, transmitter or radar), which is used in deriving 3dB beamwidth(s) from diameter or dimensions and vice versa. Frequency value must be changed before opening the details panel in order to be used for gain calculation (see note below).
Main-lobe Gain	The main-lobe gain value. Valid if Computed is not selected. Select Computed to automatically calculate the main-lobe gain based on beamwidth or diameter, efficiency, and design frequency.
Efficiency	Specify the antenna efficiency factor, ranging from 0 to 100 percent.
Back-lobe Gain	Back-lobe gain can be used two different ways: A constant gain value from 90 to 270 degrees in elevation from the boresight of the antenna. Modeled as a fraction of the Main-lobe Gain, but in the opposite direction. For example, boresight gain is computed at a 0 degree elevation angle, the back-lobe attenuation factor is applied and the result is used as the gain at the 180 degree elevation angle. The backlobe gain is a mirror image of the forward gain, but with the backlobe gain applied as an attenuation factor. If “Use as main-lobe attenuation” is selected, the attenuation factor is applied on the main-lobe gain and the result is used in the back-lobe direction.