Data Provider Elements

Ephemeris Diff in Curvilinear Coordinates

The relative ephemeris of the assigned object with respect to the primary object, expressed in curvilinear coordinates, as a function of time. It produces three coordinates and their rates (Crossrange, Downrange, and Crosstrack) that are defined relative to the osculating orbit of the reference satellite.

Available for these objects: Satellite

Type: Time-varying data.

Availability: Reports | Graphs | Dynamic Displays | Strip Charts

Pre-data required: "<TruncObjectPath>" - e.g. "Satellite/Sat1"

Data Provider Elements

Name	Dimension	Type	Description
Time	Date	Real Number or Text	Time.
Crossrange	Distance	Real Number	Cross range is in the orbit plane along the outward normal to the osculating orbital ellipse.
Downrange	Distance	Real Number	Down range is along the curved orbit in the direction of flight.
Crosstrack	Distance	Real Number	Cross track is orthogonal to the osculating orbital plane completing the right-handed triad.
Crossrange Rate	Rate	Real Number	Rate of change of the cross range coordinate.
Downrange Rate	Rate	Real Number	Rate of change of the down range coordinate.
Crosstrack Rate	Rate	Real Number	Rate of change of the cross track coordinate.
Position Cov Sigma	Unitless	Real Number	Position difference measured in terms of the position covariance. Reports N where the current relative position vector lies on a N sigma ellipsoid, where the ellipsoid if obtained from the position covariance of the primary satellite. This can only be computed if position covariance is available.
Position Combined Cov Sigma	Unitless	Real Number	Position difference measured in terms of the combined position covariance of primary and target satellites. Reports N where the current relative position vector lies on an N sigma ellipsoid, where the ellipsoid is obtained from the sum of the covariances matrices of the two objects. This can only be computed if position covariance is available.