Description

Allows the user to configure and propagate a vehicle using the GPS propagator.

Public Methods

Propagates the satellite's path using the specified time interval.

Public Properties

AutoUpdate	Allows configuring the auto-update parameters and settings. AutoUpdateEnabled must be set to true in order to be able to change the auto-update properties.
AutoUpdateEnabled	Whether automatic update is enabled.
AvailablePRNs	Returns an array of available satellite Ids.
EphemerisInterval	Get the propagator's ephemeris interval.
PRN	Gets or sets the satellite PRN number per ICD-GPS-200. This is a required data item as it is the GPS user's primary means of identifying GPS satellites. It is equivalent to the space vehicle identification (SVID) number of the satellite.
SpecifyCatalog	Specify a catalog. AutoUpdateEnabled must be set to false in order to select an almanac.
Step	Step size. Uses Time Dimension.

CoClasses that Implement IAgVePropagatorGPS

Name
AgVePropagatorGPS

Example

Set the satellite to use the GPS propagator

[C#]

// Set propagator to GPS
satellite.SetPropagatorType(AgEVePropagatorType.ePropagatorGPS);

// Get the GPS propagator
IAgVePropagatorGPS propagator = satellite.Propagator as IAgVePropagatorGPS;

Configure the GPS propagator with an almanac

[C#]

// Configure properties
// Use the scenario's analysis interval
propagator.EphemerisInterval.SetImplicitInterval(scenario.Vgt.EventIntervals["AnalysisInterval"]);

// PRN must be set before configuring GPS almanac
propagator.PRN = Int32.Parse((string)propagator.AvailablePRNs.GetValue(0));
// Turn the Auto-update off
propagator.AutoUpdateEnabled = false;
// Specify a catalog
propagator.SpecifyCatalog.Filename = almanacPath;

// Configure the properties specific to the chosen almanac
switch (propagator.SpecifyCatalog.Properties.Type)
{
    case AgEVeGPSAlmanacType.eGPSAlmanacTypeSEM:
        {
            /* configure the SEM almanac */
            IAgVeGPSAlmanacPropertiesSEM sem = propagator.SpecifyCatalog.Properties as IAgVeGPSAlmanacPropertiesSEM;
            sem.ReferenceWeek = AgEGPSReferenceWeek.eGPSReferenceWeek22Aug1999;
            break;
        }
    case AgEVeGPSAlmanacType.eGPSAlmanacTypeSP3:
        {
            /* SP3 almanac contains no configurable properties */
            IAgVeGPSAlmanacPropertiesSP3 sp3 = propagator.SpecifyCatalog.Properties as IAgVeGPSAlmanacPropertiesSP3;
            break;
        }
    case AgEVeGPSAlmanacType.eGPSAlmanacTypeYUMA:
        {
            /* configure the YUMA almanac */
            IAgVeGPSAlmanacPropertiesYUMA yuma = propagator.SpecifyCatalog.Properties as IAgVeGPSAlmanacPropertiesYUMA;
            yuma.ReferenceWeek = AgEGPSReferenceWeek.eGPSReferenceWeek22Aug1999;
            break;
        }
}

// Propagate
propagator.Propagate();

Configure the GPS propagator with an almanac

[Visual Basic .NET]

' Configure properties
' Use the scenario's analysis interval
propagator.EphemerisInterval.SetImplicitInterval(scenario.Vgt.EventIntervals("AnalysisInterval"))

' PRN must be set before configuring GPS almanac
propagator.PRN = Int32.Parse(DirectCast(propagator.AvailablePRNs.GetValue(0), String))

' Turn the Auto-update off
propagator.AutoUpdateEnabled = False

' Specify a catalog
propagator.SpecifyCatalog.Filename = almanacPath

' Configure the properties specific to the chosen almanac
Select Case propagator.SpecifyCatalog.Properties.Type
	Case AgEVeGPSAlmanacType.eGPSAlmanacTypeSEM
		If True Then
			' configure the SEM almanac 

			Dim sem As IAgVeGPSAlmanacPropertiesSEM = TryCast(propagator.SpecifyCatalog.Properties, IAgVeGPSAlmanacPropertiesSEM)
			sem.ReferenceWeek = AgEGPSReferenceWeek.eGPSReferenceWeek22Aug1999
			Exit Select
		End If
	Case AgEVeGPSAlmanacType.eGPSAlmanacTypeSP3
		If True Then
			' SP3 almanac contains no configurable properties 

			Dim sp3 As IAgVeGPSAlmanacPropertiesSP3 = TryCast(propagator.SpecifyCatalog.Properties, IAgVeGPSAlmanacPropertiesSP3)
			Exit Select
		End If
	Case AgEVeGPSAlmanacType.eGPSAlmanacTypeYUMA
		If True Then
			' configure the YUMA almanac 

			Dim yuma As IAgVeGPSAlmanacPropertiesYUMA = TryCast(propagator.SpecifyCatalog.Properties, IAgVeGPSAlmanacPropertiesYUMA)
			yuma.ReferenceWeek = AgEGPSReferenceWeek.eGPSReferenceWeek22Aug1999
			Exit Select
		End If
End Select

' Propagate
propagator.Propagate()

Set the satellite to use the GPS propagator

[Visual Basic .NET]

' Set propagator to GPS
satellite.SetPropagatorType(AgEVePropagatorType.ePropagatorGPS)

' Get the GPS propagator
Dim propagator As IAgVePropagatorGPS = TryCast(satellite.Propagator, IAgVePropagatorGPS)

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IAgVePropagatorGPS Interface