Field of View Commands

field_of_view <field-of-view-type>
   ... Type Commands ...
end_field_of_view

Field of views specify geometrical limits to determine if a subsystem can potentially interact with another object. Field of views are valid for anything that uses an electromagnetic antenna, including transmitter, receiver.

<field-of-view-type> can be:

Each type have their own unique input keywords.

Available Fields of View

rectangular

field_of_view rectangular
   azimuth_field_of_view <angle-value> <angle-value>
   elevation_field_of_view <angle-value> <angle-value>
end_field_of_view

Defines a field of view with azimuth and elevation extents.

azimuth_field_of_view <angle-value> <angle-value>

Specify the minimum and maximum angle about which the subsystem can see in azimuth. The limits are with respect to the current cue. In general these values should be greater than or equal to the azimuth_scan_limits (possibly accounting for the width of the beam when the subsystem is positioned to its scan limit).

Default -180.0 degrees to 180 degrees

Note

These values are used only for initial screening to determine if the object can potentially interact with another object.

elevation_field_of_view <angle-value> <angle-value>

Specifies the minimum and maximum angle about which the subsystem can see in elevation. The limits are with respect to the current cue. In general these values should be greater than or equal to the azimuth_scan_limits (possibly accounting for the width of the beam when the subsystem is positioned to its scan limit).

Default -90.0 degrees to 90 degrees

Note

This is the default field of view type.

circular

field_of_view circular
   half_angle <angle-value>
end_field_of_view

Defines a field of view that is circular, defining a conical solid angle.

half_angle <angle-value>

Specify the half angle from the center to the edge of the circle that the subsystem can see.

polygonal

field_of_view polygonal
   azimuth_elevation <angle-value> <angle_value>  # 1st point
   azimuth_elevation <angle-value> <angle_value>  # 2nd point
   azimuth_elevation <angle-value> <angle_value>  # 3rd point
   ...
   azimuth_elevation <angle-value> <angle_value>  # nth point
end_field_of_view

Defines a field of view that is polygonal, as defined by a series of azimuth_elevation values from the eyepoint. At least three values are required.

azimuth_elevation <angle-value> <angle-value>

Specify the az and el values to a point defining the polygonal field of view.

equatorial

field_of_view equatorial
   equatorial_field_of_view <angle-value> <angle-value>
   polar_field_of_view <angle-value> <angle-value>
end_field_of_view

Defines a field of view that is rectangular but, unlike the rectangular field of view, has as its sphere of orientation a celestial sphere with equator matching the earth’s projected, instantaneous equator, rather than a celestial sphere with equator matching the local horizon (i.e., the North-East plane in the local North-East-Down coordinate system). The difference between an equatorial field of view and similarly defined rectangular field of view is a rotation by the parallactic angle about the sensor’s pointing direction.

equatorial_field_of_view <angle-value> <angle-value>

Specify the minimum and maximum angle about which the subsystem can see in the equatorial coordinate (azimuthal angle of the equatorial celestial sphere). The limits are with respect to the current cue.

Default -180.0 degrees to 180 degrees

Note

These values are used only for initial screening to determine if the object can potentially interact with another object.

polar_field_of_view <angle-value> <angle-value>

Specifies the minimum and maximum angle about which the subsystem can see in the polar coordinate (polar angle of the equatorial celestial sphere). The limits are with respect to the current cue.

Default -90.0 degrees to 90 degrees