STK Antenna Models

Hemispheric Antenna Pattern

The Hemispherical antenna type provides a built-in model antenna gain pattern covering half of the hemisphere along the boresight. An example of this type of antenna is the common, commercially available GPS receiver antenna.

This antenna uses a polar coordinate system.

Field Description
Design Frequency

The frequency of the antenna.

For an embedded antenna on a receiver, transmitter or radar, this value corresponds to the Frequency entered on the Model Specs tab for the transmitter or receiver and the Transmitter Specs tab for the Radar.

For an antenna linked to a receiver, transmitter, or radar, the Antenna Design Frequency value gets overridden by the Frequency value set on the Model Specs tab for the transmitter or receiver, and the on the Transmitter Specs tab for the Radar. However, when computing the antenna's gain matrix (or a link budget, etc.) from one of the objects linking to the antenna, that other object's frequency settings override the antenna's Design Frequency setting.

Main-lobe Gain Read-only field displaying the total gain of the antenna in dB or the selected units.
Efficiency The efficiency factor of the antenna, varying from 0 to 100 percent. Since no antenna is perfect, the efficiency factor allows you to specify the degradation in performance. Typical values fall in the range of 70 to 90 percent.