SpacecraftObservation Object

The SpacecraftObservation object holds Measurements associated with a Sensor attached to one Spacecraft observing another Spacecraft at an instant in time. The Measurements for a SpacecraftObservation can include Range, RangeRate, Azimuth, and Elevation. The Azimuth and Elevation measurements are computed relative to the reference frame of the observing Sensor.

Available In Editions:

Timing Precision Mode

This page describes functionality in millisecond timing precision mode. Millisecond timing precision mode is deprecated and will be removed in a future release. We recommend that you migrate your Mission Plans to nanosecond timing precision mode.

Signatures	Description
SpacecraftObservation()	Create a SpacecraftObservation object without associating it with any other objects.
SpacecraftObservation(Sensor sensorTakingMeasurement, Spacecraft objectBeingMeasured)	Create a SpacecraftObservation object, and associate it with the "objectTakingMeasurement" and "objectBeingMeasured".
SpacecraftObservation(Sensor sensorTakingMeasurement, Transponder transponderObjectBeingMeasured)	Create a SpacecraftObservation object, and associate it with the "objectTakingMeasurement" and "transponderObjectBeingMeasured".
SpacecraftObservation(Sensor sensorTakingMeasurement, Transponder transponderObjectBeingMeasured, Sensor sensorReceivingSignal)	Create a SpacecraftObservation object, and associate it with the "objectTakingMeasurement", "transponderObjectBeingMeasured", and "sensorReceivingSignal".

Name	Description	Attributes
AngleType	A flag indicating which angle pair to process, either Azimuth/Elevation or Right Ascension/Declination measurements.	Type: Variable Access: Read/Write
Azimuth	The Azimuth measurement associated with this SpacecraftObservation, measured in the Sensor frame of the observing Sensor.	Type: Measurement Access: Read-Only
DeclaredName	The name of the object as declared.	Type: String Access: Read-Only
Declination	The Declination measurement associated with this SpacecraftObservation, measured in the True Equator, Mean Equinox frame.	Type: Measurement Access: Read-Only
Elevation	The Elevation measurement associated with this SpacecraftObservation, measured in the Sensor frame of the observing Sensor.	Type: Measurement Access: Read-Only
Name	The name displayed for this object in output windows such as views, plots, and reports.	Type: String Access: Read/Write
ObjectBeingObserved	The Spacecraft being tracked by the Sensor.	Type: Object Access: Read-Only
ObjectId	The unique identifier for the object.	Type: Variable Access: Read-Only
ObjectType	The type of the object.	Type: String Access: Read-Only
ObservedEpoch	The epoch of the Observation in TAI.	Type: Variable Access: Read/Write Units: day
ObservedSensor	The Sensor attached to the Transponder being observed. The Sensor's X, Y, and Z position properties will be used to model an offset from the origin of the Spacecraft BCS when modeling measurements. This property is optional.	Type: Sensor Access: Read-Only
Observer	The Sensor that is transmitting the tracking signal.	Type: Object Access: Read-Only
ObserverPosition	The position of the observing sensor or spacecraft in the ICRF at the epoch of the observation.	Type: Array Access: Read/Write Units: km
Range	The Range measurement associated with this SpacecraftObservation.	Type: Measurement Access: Read-Only
RangeRate	The Range-Rate measurement associated with this SpacecraftObservation.	Type: Measurement Access: Read-Only
RightAscension	The Right Ascension measurement associated with this SpacecraftObservation, measured in the True Equator, Mean Equinox frame.	Type: Measurement Access: Read-Only
UseAzimuth	A flag indicating whether or not the Azimuth measurement will be used.	Type: Variable Access: Read/Write
UseDeclination	A flag indicating whether or not the Declination measurement will be used.	Type: Variable Access: Read/Write
UseElevation	A flag indicating whether or not the Elevation measurement will be used.	Type: Variable Access: Read/Write
UseIonosphericCorrection	A flag indicating whether or not the Ionospheric correction will be used.	Type: Variable Access: Read/Write
UseLightTimeCorrection	A flag indicating whether or not the Light-Time correction will be used.	Type: Variable Access: Read/Write
UseMeasurementWeighting	A flag indicating whether or not to perform measurement weighting using internal geometric-based expressions. Measurement weighting should be turned off if a custom Measurement Noise model is implemented at the script level.	Type: Variable Access: Read/Write
UseObserverPosition	A flag indicating whether or not to specify the position of the observing Sensor, using the ObserverPosition array. This cannot be used when both UseRange and UseLightTimeCorrection are enabled. Note: The UseObserverPosition property should only be applied when you are reading in and processing actual observations, and not simulated observations, from a Spacecraft Observation file that contains the observer position given in km, in the ICRF.	Type: Variable Access: Read/Write
UseRange	A flag indicating whether or not the Range measurement will be used.	Type: Variable Access: Read/Write
UseRangeRate	A flag indicating whether or not the Range-Rate measurement will be used.	Type: Variable Access: Read/Write
UseRightAscension	A flag indicating whether or not the Right Ascension measurement will be used.	Type: Variable Access: Read/Write
WasUnderweightingUsed	A flag indicating whether or not measurement underweighting was used as part of the filter state and covariance update for this observation.	Type: Variable Access: Read-Only

SpacecraftObservation Object

Description

Available In Editions:

Timing Precision Mode