Package org.orekit.propagation.analytical.gnss

Class GLONASSAnalyticalPropagator

java.lang.Object

org.orekit.propagation.AbstractPropagator

org.orekit.propagation.analytical.AbstractAnalyticalPropagator

org.orekit.propagation.analytical.gnss.GLONASSAnalyticalPropagator

All Implemented Interfaces:

Propagator, PVCoordinatesProvider

public class GLONASSAnalyticalPropagator
extends AbstractAnalyticalPropagator

This class aims at propagating a GLONASS orbit from GLONASSOrbitalElements.

Caution: The Glonass analytical propagator can only be used with GLONASSAlmanac. Using this propagator with a GLONASSFdmaNavigationMessage is prone to error.

Since:

10.0

Author:

Bryan Cazabonne

See Also:

• GLONASS Interface Control Document

Field Summary

Fields inherited from interface org.orekit.propagation.Propagator

DEFAULT_MASS

Method Summary

Modifier and Type	Method	Description
Frame	getECEF()	Gets the Earth Centered Earth Fixed frame used to propagate GLONASS orbits.
Frame	getECI()	Gets the Earth Centered Inertial frame used to propagate the orbit.
Frame	getFrame()	Get the frame in which the orbit is propagated.
GLONASSOrbitalElements	getGLONASSOrbitalElements()	Gets the underlying GLONASS orbital elements.
protected double	getMass(AbsoluteDate date)	Get the mass.
static double	getMU()	Get the Earth gravity coefficient used for GLONASS propagation.
PVCoordinates	propagateInEcef(AbsoluteDate date)	Gets the PVCoordinates of the GLONASS SV in ECEF frame.
Orbit	propagateOrbit(AbsoluteDate date)	Extrapolate an orbit up to a specific target date.
void	resetInitialState(SpacecraftState state)	Reset the propagator initial state.
protected void	resetIntermediateState(SpacecraftState state, boolean forward)	Reset an intermediate state.

Methods inherited from class org.orekit.propagation.analytical.AbstractAnalyticalPropagator

acceptStep, addEventDetector, basicPropagate, clearEventsDetectors, clearMatricesComputation, getEphemerisGenerator, getEventDetectors, getJacobiansColumnsNames, getPvProvider, propagate

Methods inherited from class org.orekit.propagation.AbstractPropagator

addAdditionalDataProvider, createHarvester, getAdditionalDataProviders, getAttitudeProvider, getHarvester, getInitialState, getManagedAdditionalData, getMultiplexer, getStartDate, initializeAdditionalData, initializePropagation, isAdditionalDataManaged, propagate, removeAdditionalDataProvider, setAttitudeProvider, setStartDate, setupMatricesComputation, stateChanged, updateAdditionalData, updateUnmanagedData

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface org.orekit.propagation.Propagator

clearStepHandlers, getPosition, getPVCoordinates, getVelocity, setStepHandler, setStepHandler

Method Details

propagateInEcef

public PVCoordinates propagateInEcef(AbsoluteDate date)

Gets the PVCoordinates of the GLONASS SV in ECEF frame.

The algorithm is defined at Appendix M.1 from GLONASS Interface Control Document, with automatic differentiation added to compute velocity and acceleration.

Parameters:

date - the computation date

Returns:

the GLONASS SV PVCoordinates in ECEF frame

getMass

protected double getMass(AbsoluteDate date)

Get the mass.

Specified by:

getMass in class AbstractAnalyticalPropagator

Parameters:

date - target date for the orbit

Returns:

mass mass

getMU

public static double getMU()

Get the Earth gravity coefficient used for GLONASS propagation.

Returns:

the Earth gravity coefficient.

getGLONASSOrbitalElements

public GLONASSOrbitalElements getGLONASSOrbitalElements()

Gets the underlying GLONASS orbital elements.

Returns:

the underlying GLONASS orbital elements

getECI

public Frame getECI()

Gets the Earth Centered Inertial frame used to propagate the orbit.

Returns:

the ECI frame

getECEF

public Frame getECEF()

Gets the Earth Centered Earth Fixed frame used to propagate GLONASS orbits.

Returns:

the ECEF frame

getFrame

public Frame getFrame()

Get the frame in which the orbit is propagated.

The propagation frame is the definition frame of the initial state, so this method should be called after this state has been set, otherwise it may return null.

Specified by:

getFrame in interface Propagator

Overrides:

getFrame in class AbstractPropagator

Returns:

frame in which the orbit is propagated

See Also:

• Propagator.resetInitialState(SpacecraftState)

resetInitialState

public void resetInitialState(SpacecraftState state)

Reset the propagator initial state.

Specified by:

resetInitialState in interface Propagator

Overrides:

resetInitialState in class AbstractPropagator

Parameters:

state - new initial state to consider

resetIntermediateState

protected void resetIntermediateState(SpacecraftState state,
 boolean forward)

Reset an intermediate state.

Specified by:

resetIntermediateState in class AbstractAnalyticalPropagator

Parameters:

state - new intermediate state to consider

forward - if true, the intermediate state is valid for propagations after itself

propagateOrbit

public Orbit propagateOrbit(AbsoluteDate date)

Extrapolate an orbit up to a specific target date.

Specified by:

propagateOrbit in class AbstractAnalyticalPropagator

Parameters:

date - target date for the orbit

Returns:

extrapolated parameters