Cosecant Squared Pattern Antenna

This antenna models the Cosecant Squared pattern up to the cutoff angle. Side lobes above the cutoff angle are Sinc Pattern. You can choose from a selection of lateral side-lobe types. The default is Constant.

For the Cosecant Squared Pattern Antenna, STK 12 and later uses an improved model with more features. The attributes Alpha 1, Alpha 2, and Alpha M are no longer valid. AGI recommends that, for all scenarios generated by older versions of STK, you update the scenario by selecting the appropriate attributes on the current model. You can also select the Sidelobe Type "Constant Level" as a reasonable match to the older model.

This antenna uses a polar coordinate system.

You can specify the following parameters:

Parameter	Description
Sidelobe Type	Select a model for the gain pattern type outside the Cosecant Squared region. Options are Constant Level, Gaussian, Parabolic, Sinc, and Square Horn.
Beamwidth	This is the beam width of the main lobe of the gain pattern. STK computes the Cosecant Squared pattern outside this region in the positive elevation direction.
Design Frequency	This is the frequency of the antenna. The antenna design frequency is independent of the operational frequency of a transmitter, receiver, or radar. Changing the frequency of a transmitter, receiver, or radar does not update an embedded antenna's design frequency, nor vice versa. The design frequency is solely used at antenna configuration time to compute the antenna size from its max gain or beamwidth settings. A mismatch between signal frequency and antenna design frequency typically causes performance degradation.
Cutoff Angle	This is the maximum elevation angle at which STK computes the Cosecant Squared pattern. STK computes the Cosecant Squared Pattern for the outside region, from the main beamwidth up to the Cutoff Angle.
Main-lobe Gain	This is the main lobe gain of the antenna pattern.
Back-lobe Gain	You can use Back-lobe Gain two different ways: When the Sidelobe Type selection is Constant Level, STK applies the back-lobe gain value outside the region defined by the main beam of the antenna. STK sets the constant gain value as the side-lobe of the antenna in the front hemisphere of the gain pattern and applies the same value as the back lobe of the antenna. When the Sidelobe Type selection is other than Constant Level, STK defines the side lobes of the gain pattern by the Sidelobe type selection and computes these side lobes for the front hemisphere of the gain pattern. STK applies the Back-lobe Gain to the back hemisphere of the gain pattern. The back hemisphere of the gain pattern is always constant.
Efficiency	This is the efficiency of the antenna, a value between 0 and 100 percent.