The Facility Object

The Facility object models a ground station or other facility on the surface of the central body. Select one or more of the following to model a facility, impose constraints, and define the facility's subobjects:

Basic Properties

Property Description
Position Define the location of the facility using one of several available position types.
AzElMask Use terrain data or a mask file to define an azimuth-elevation mask for the facility.
Terrain Slope Define the scope of the local terrain.
Description Record useful information about the facility.

2D Graphics Properties

Property Description
Attributes Define color and marker style for the facility, and opt whether to inherit or override the global setting for label display.
AzElMask Control the display of azimuth-elevation mask properties in the 2D Graphics window.
Range Define range contours representing the various regions of the surface that can see an object at the specified level.
Display Times Set time intervals during which facility graphics display.

3D Graphics Properties

Property Description
Vector Control the display of vectors and other geometric elements related to the facility.
Attitude Sphere The Attitude Sphere is a visualization aid that when combined with vector display constitutes a powerful tool for displaying the object's attitude and for tracking attitude changes over time.
Model Specify a model to represent the facility in the 3D Graphics window, and then scale the model and adjust the position of any model articulations.
Offsets Position a model and marker representing the facility in the 3D Graphics window by offsetting the object from its reference frame.
AzElMask Control the display of azimuth-elevation mask properties in the 3D Graphics window.
Range Display range contours for the facility. Range contours display in accordance with the values set for 2D Graphics Range Contours for the object.
Model Pointing Point parts of the facility model toward a target, such as the Sun or Earth.
Data Display Display dynamic data for the facility in the 3D Graphics window.
Vapor Trail Add a vapor trail to the facility.

Constraints

Property Description
Basic Impose a variety of standard access constraints (azimuth and elevation angle and rate, range and range rate, propagation delay, etc.) from a facility to another object.
Sun Impose a variety of access constraints from the facility to another object based on the position of the Sun and the Moon.
Temporal Impose time-based access constraints from the facility to another object.
Vector Constrain access computations with respect to any valid vector or angle.
Special Special access constraints are defined in terms of geostationary belt exclusion, height above horizon, terrain grazing angle and exclusion of other scenario objects.
Search/Track

Radar Search/Track Constraints property pages allow minimum and maximum values to be entered for several parameters and presents a variety of doppler options:

  • Search/Track. These parameters correspond to the radar's main channel. These parameters account for the polarization mismatch, if polarization is selected on the Basic Polarization page.
  • ST w/Jamming. These parameters correspond to the main channel radar receiver that is under the influence of jamming. When the radar receiver polarization is set and the jammers are polarized, the search/track parameters take polarization mismatch into account. Most of these parameters are re-computed under the impact of jamming on the radar receiver main channel. For more information on the effects of jamming on constraints, see Constraints with Jamming.
  • S/T OrthoPol. These parameters correspond to the radar's orthogonal polarization channel.
  • S/T OrthoPolJam. These parameters correspond to the radar's orthogonal polarization channel under the threat of jamming.

The STK/Radar SAR computation and constraints can be extended with the Search/Track plug-in constraint. See Search Track User Plugin.
SAR

SAR property pages allow for the imposition of a variety of constraints on synthetic aperture (SAR) radar.

  • SAR. These parameters correspond to the main channel (SAR).
  • SAR w/Jamming. These parameters correspond to the main channel under jamming. For more information on the effects of jamming on constraints, see Constraints with Jamming.
  • SAR OrthoPol. These parameters are enabled when the receiver side orthogonal polarization is selected.
  • SAR OrthoPolJam. These parameters are enabled when the receiver side orthogonal polarization is selected. For more information on the effects of jamming on constraints, see Constraints with Jamming.

The STK/Radar SAR computation and constraints can be extended with the Search/Track plug-in constraint. See SAR User Plugin.
Plugins An interface is provided for defining custom constraints in terms of user-supplied scripts created in Perl, VBScript and MATLAB.

RF Properties

Property Description
Atmosphere Specify the local surface atmospheric conditions used by the gaseous absorption and rain models.
RCS Specify the radar cross section (RCS) parameters.

Subobjects

You can attach the following subobjects to a facility: