Package org.orekit.estimation.measurements.signal

Class FieldSignalTravelTimeAdjustableEmitter<T extends CalculusFieldElement<T>>

java.lang.Object

org.orekit.estimation.measurements.signal.FieldSignalTravelTimeAdjustableEmitter<T>

public class FieldSignalTravelTimeAdjustableEmitter<T extends CalculusFieldElement<T>>
extends Object

Class for computing signal time of travel with an adjustable emitter and a fixed receiver's position and date. The delay is calculated via a fixed-point algorithm with customizable settings (even enabling instantaneous transmission).

Since:

14.0

Author:

Romain Serra

See Also:

SignalTravelTimeAdjustableEmitter

Field Summary

Fields

Modifier and Type	Field	Description
protected static double	C_RECIPROCAL	Reciprocal for light speed.

Constructor Summary

Constructors

Constructor	Description
FieldSignalTravelTimeAdjustableEmitter(FieldPVCoordinatesProvider<T> adjustableEmitterPVProvider)	Constructor with default iteration settings.
FieldSignalTravelTimeAdjustableEmitter(FieldPVCoordinatesProvider<T> adjustableEmitterPVProvider, ConvergenceChecker<T> convergenceChecker)	Constructor.

Method Summary

Modifier and Type	Method	Description
protected T	compute(FieldPVCoordinatesProvider<T> pvCoordinatesProvider, T initialOffset, FieldVector3D<T> fixedPosition, FieldAbsoluteDate<T> guessDate, Frame frame)	Compute propagation delay on a link leg (typically downlink or uplink).
T	computeDelay(FieldVector3D<T> receiverPosition, FieldAbsoluteDate<T> signalArrivalDate, Frame frame)	Compute propagation delay on a link leg (typically downlink or uplink) without custom guess.
T	computeDelay(FieldAbsoluteDate<T> approxEmissionDate, FieldVector3D<T> receiverPosition, FieldAbsoluteDate<T> signalArrivalDate, Frame frame)	Compute propagation delay on a link leg (typically downlink or uplink).
protected T	computeShift(T offset, T delay)	Computes the time shift.
ConvergenceChecker<T>	getConvergenceChecker()	Getter for the convergence checker.
static <S extends CalculusFieldElement<S>> FieldSignalTravelTimeAdjustableEmitter<S>	of(FieldSpacecraftState<S> state)	Build instance from spacecraft state.

Methods inherited from class java.lang.Object

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

Field Detail

C_RECIPROCAL

protected static final double C_RECIPROCAL

Reciprocal for light speed.

See Also:

Constant Field Values

Constructor Detail

FieldSignalTravelTimeAdjustableEmitter

public FieldSignalTravelTimeAdjustableEmitter(FieldPVCoordinatesProvider<T> adjustableEmitterPVProvider)

Constructor with default iteration settings.

Parameters:

adjustableEmitterPVProvider - adjustable emitter

FieldSignalTravelTimeAdjustableEmitter

public FieldSignalTravelTimeAdjustableEmitter(FieldPVCoordinatesProvider<T> adjustableEmitterPVProvider,
                                              ConvergenceChecker<T> convergenceChecker)

Constructor.

Parameters:

adjustableEmitterPVProvider - adjustable emitter

convergenceChecker - convergence checker for fixed-point algorithm

Method Detail

of

public static <S extends CalculusFieldElement<S>> FieldSignalTravelTimeAdjustableEmitter<S> of(FieldSpacecraftState<S> state)

Build instance from spacecraft state.

Type Parameters:

S - field type

Parameters:

state - spacecraft state

Returns:

signal travel time computer

computeDelay

public T computeDelay(FieldVector3D<T> receiverPosition,
                      FieldAbsoluteDate<T> signalArrivalDate,
                      Frame frame)

Compute propagation delay on a link leg (typically downlink or uplink) without custom guess.

Parameters:

receiverPosition - fixed position of receiver at signalArrivalDate

signalArrivalDate - date at which the signal arrives to receiver

frame - Inertial frame in which receiver is defined.

Returns:

positive delay between signal emission and signal reception dates

computeDelay

public T computeDelay(FieldAbsoluteDate<T> approxEmissionDate,
                      FieldVector3D<T> receiverPosition,
                      FieldAbsoluteDate<T> signalArrivalDate,
                      Frame frame)

Compute propagation delay on a link leg (typically downlink or uplink).

Parameters:

approxEmissionDate - approximate emission date

receiverPosition - fixed position of receiver at signalArrivalDate

signalArrivalDate - date at which the signal arrives to receiver

frame - Inertial frame in which receiver is defined.

Returns:

positive delay between signal emission and signal reception dates

computeShift

protected T computeShift(T offset,
                         T delay)

Computes the time shift.

Parameters:

offset - time offset

delay - time delay

Returns:

time shift to use in computation

getConvergenceChecker

public ConvergenceChecker<T> getConvergenceChecker()

Getter for the convergence checker.

Returns:

checker

compute

protected T compute(FieldPVCoordinatesProvider<T> pvCoordinatesProvider,
                    T initialOffset,
                    FieldVector3D<T> fixedPosition,
                    FieldAbsoluteDate<T> guessDate,
                    Frame frame)

Compute propagation delay on a link leg (typically downlink or uplink). The max. iteration number and convergence checker can be tweaked to emulate no-delay a.k.a. instantaneous transmission.

Parameters:

pvCoordinatesProvider - adjustable emitter/receiver

initialOffset - guess for the time off set

fixedPosition - fixed receiver/emitter position

guessDate - guess for emission/reception date

frame - Inertial frame in which receiver/emitter is defined.

Returns:

positive delay between signal emission and signal reception dates