Package org.orekit.estimation.sequential

Class ConstantProcessNoise

java.lang.Object

org.orekit.estimation.sequential.AbstractCovarianceMatrixProvider

org.orekit.estimation.sequential.ConstantProcessNoise

All Implemented Interfaces:

CovarianceMatrixProvider

public class ConstantProcessNoise
extends AbstractCovarianceMatrixProvider

Provider for constant process noise matrices.

This class always provides one initial noise matrix and one constant process noise matrix (both can be identical), regardless of states.

Since:

9.2

Author:

Luc Maisonobe

Constructor Summary

Constructors

Constructor	Description
ConstantProcessNoise(RealMatrix processNoiseMatrix)	Simple constructor.
ConstantProcessNoise(RealMatrix initialNoiseMatrix, RealMatrix processNoiseMatrix)	Simple constructor.

Method Summary

Modifier and Type	Method	Description
RealMatrix	getProcessNoiseMatrix(SpacecraftState previous, SpacecraftState current)	Get the process noise matrix between previous and current states.

Methods inherited from class org.orekit.estimation.sequential.AbstractCovarianceMatrixProvider

getInitialCovarianceMatrix

Methods inherited from class java.lang.Object

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

Constructor Detail

ConstantProcessNoise

public ConstantProcessNoise(RealMatrix processNoiseMatrix)

Simple constructor.

Parameters:

processNoiseMatrix - constant process noise, used for both initial noise and noise between previous and current state

ConstantProcessNoise

public ConstantProcessNoise(RealMatrix initialNoiseMatrix,
                            RealMatrix processNoiseMatrix)

Simple constructor.

Parameters:

initialNoiseMatrix - initial process noise

processNoiseMatrix - constant process noise

Method Detail

getProcessNoiseMatrix

public RealMatrix getProcessNoiseMatrix(SpacecraftState previous,
                                        SpacecraftState current)

Get the process noise matrix between previous and current states.

The process noise matrix is a covariance matrix corresponding to the parameters managed by the Kalman estimator. The number of rows/columns and their order are as follows:

• The first 6 components correspond to the 6 orbital parameters of the associated propagator. All 6 parameters must always be present, regardless of the fact they are estimated or not.
• The following components correspond to the subset of propagation parameters of the associated propagator that are estimated.
• The remaining components correspond to the subset of measurements parameters that are estimated, considering all measurements, even the ones that correspond to spacecrafts not related to the associated propagator

In most cases, the process noise for the part corresponding to measurements (the final rows and columns) will be set to 0 for the process noise corresponding to the evolution between a non-null previous and current state.

Parameters:

previous - previous state

current - current state

Returns:

physical (i.e. non normalized) process noise matrix between previous and current states

See Also:

PropagatorBuilder.getOrbitalParametersDrivers(), PropagatorBuilder.getPropagationParametersDrivers()