Package com.irurueta.navigation.gnss

Class GNSSKalmanEpochEstimator

java.lang.Object

com.irurueta.navigation.gnss.GNSSKalmanEpochEstimator

public class GNSSKalmanEpochEstimator
extends Object

Implements one cycle of the GNSS extended Kalman filter. This implementation is based on the equations defined in "Principles of GNSS, Inertial, and Multi-sensor Integrated Navigation Systems, Second Edition" and on the companion software available at: https://github.com/ymjdz/MATLAB-Codes/blob/master/GNSS_KF_Epoch.m

Field Summary

Fields

Modifier and Type	Field	Description
static final double	EARTH_ROTATION_RATE	Earth rotation rate expressed in radians per second (rad/s).
private static final int	MATRIX_SIZE	Number of rows and columns of transition and system noise covariance matrices.
static final double	SPEED_OF_LIGHT	Speed of light in the vacuum expressed in meters per second (m/s).

Constructor Summary

Constructors

Modifier	Constructor	Description
private	GNSSKalmanEpochEstimator()	Constructor.

Method Summary

Modifier and Type	Method	Description
private static double	convertTime(com.irurueta.units.Time time)	Converts time instance into a value expressed in seconds.
static void	estimate(Collection<GNSSMeasurement> measurements, double propagationInterval, GNSSEstimation previousEstimation, com.irurueta.algebra.Matrix previousCovariance, GNSSKalmanConfig config, GNSSEstimation updatedEstimation, com.irurueta.algebra.Matrix updatedCovariance)	Estimates the update of Kalman filter state and covariance matrix for a single epoch.
static GNSSKalmanState	estimate(Collection<GNSSMeasurement> measurements, double propagationInterval, GNSSKalmanState previousState, GNSSKalmanConfig config)	Estimates the update of Kalman filter state and covariance matrix for a single epoch.
static void	estimate(Collection<GNSSMeasurement> measurements, double propagationInterval, GNSSKalmanState previousState, GNSSKalmanConfig config, GNSSKalmanState result)	Estimates the update of Kalman filter state and covariance matrix for a single epoch.
static void	estimate(Collection<GNSSMeasurement> measurements, com.irurueta.units.Time propagationInterval, GNSSEstimation previousEstimation, com.irurueta.algebra.Matrix previousCovariance, GNSSKalmanConfig config, GNSSEstimation updatedEstimation, com.irurueta.algebra.Matrix updatedCovariance)	Estimates the update of Kalman filter state and covariance matrix for a single epoch.
static GNSSKalmanState	estimate(Collection<GNSSMeasurement> measurements, com.irurueta.units.Time propagationInterval, GNSSKalmanState previousState, GNSSKalmanConfig config)	Estimates the update of Kalman filter state and covariance matrix for a single epoch.
static void	estimate(Collection<GNSSMeasurement> measurements, com.irurueta.units.Time propagationInterval, GNSSKalmanState previousState, GNSSKalmanConfig config, GNSSKalmanState result)	Estimates the update of Kalman filter state and covariance matrix fo a single epoch.

Methods inherited from class java.lang.Object

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

Field Details

SPEED_OF_LIGHT

public static final double SPEED_OF_LIGHT

Speed of light in the vacuum expressed in meters per second (m/s).

See Also:

• Constant Field Values

EARTH_ROTATION_RATE

public static final double EARTH_ROTATION_RATE

Earth rotation rate expressed in radians per second (rad/s).

See Also:

• Constant Field Values

MATRIX_SIZE

private static final int MATRIX_SIZE

Number of rows and columns of transition and system noise covariance matrices.

See Also:

• Constant Field Values

Constructor Details

GNSSKalmanEpochEstimator

private GNSSKalmanEpochEstimator()

Constructor. Prevents instantiation of utility class.

Method Details

estimate

public static GNSSKalmanState estimate(Collection<GNSSMeasurement> measurements,
 com.irurueta.units.Time propagationInterval,
 GNSSKalmanState previousState,
 GNSSKalmanConfig config)
                                throws com.irurueta.algebra.AlgebraException

Estimates the update of Kalman filter state and covariance matrix for a single epoch.

Parameters:

measurements - satellite measurements data.

propagationInterval - propagation interval.

previousState - previous GNSS estimates and Kalman filter error covariance matrix.

config - system configuration (usually obtained through calibration).

Returns:

new Kalman filter state.

Throws:

com.irurueta.algebra.AlgebraException - if there are numerical instabilities.

estimate

public static void estimate(Collection<GNSSMeasurement> measurements,
 com.irurueta.units.Time propagationInterval,
 GNSSKalmanState previousState,
 GNSSKalmanConfig config,
 GNSSKalmanState result)
                     throws com.irurueta.algebra.AlgebraException

Estimates the update of Kalman filter state and covariance matrix fo a single epoch.

Parameters:

measurements - satellite measurements data.

propagationInterval - propagation interval.

previousState - previousGNSS estimates and Kalman filter error covariance matrix.

config - system configuration (usually obtained through calibration).

result - instance where updated Kalman filter state will be stored.

Throws:

com.irurueta.algebra.AlgebraException - if there are numerical instabilities.

estimate

public static void estimate(Collection<GNSSMeasurement> measurements,
 com.irurueta.units.Time propagationInterval,
 GNSSEstimation previousEstimation,
 com.irurueta.algebra.Matrix previousCovariance,
 GNSSKalmanConfig config,
 GNSSEstimation updatedEstimation,
 com.irurueta.algebra.Matrix updatedCovariance)
                     throws com.irurueta.algebra.AlgebraException

Estimates the update of Kalman filter state and covariance matrix for a single epoch.

Parameters:

measurements - satellite measurements data.

propagationInterval - propagation interval.

previousEstimation - previousGNSS estimates.

previousCovariance - previousKalman filter error covariance matrix.

config - system configuration (usually obtained through calibration).

updatedEstimation - instance where updated GNSS estimate will be stored after executing this method.

updatedCovariance - instance where updated Kalman filter error covariance matrix will be stored.

Throws:

IllegalArgumentException - if provided previous covariance matrix is not 8x8.

com.irurueta.algebra.AlgebraException - if there are numerical instabilities.

estimate

public static GNSSKalmanState estimate(Collection<GNSSMeasurement> measurements,
 double propagationInterval,
 GNSSKalmanState previousState,
 GNSSKalmanConfig config)
                                throws com.irurueta.algebra.AlgebraException

Estimates the update of Kalman filter state and covariance matrix for a single epoch.

Parameters:

measurements - satellite measurements data.

propagationInterval - propagation interval expressed in seconds (s).

previousState - previous GNSS estimates and Kalman filter error covariance matrix.

config - system configuration (usually obtained through calibration).

Returns:

new Kalman filter state.

Throws:

com.irurueta.algebra.AlgebraException - if there are numerical instabilities.

estimate

public static void estimate(Collection<GNSSMeasurement> measurements,
 double propagationInterval,
 GNSSKalmanState previousState,
 GNSSKalmanConfig config,
 GNSSKalmanState result)
                     throws com.irurueta.algebra.AlgebraException

Estimates the update of Kalman filter state and covariance matrix for a single epoch.

Parameters:

measurements - satellite measurements data.

propagationInterval - propagation interval expressed in seconds (s).

previousState - previous GNSS estimates and Kalman filter error covariance matrix.

config - system configuration (usually obtained through calibration).

result - instance where updated Kalman filter state will be stored.

Throws:

com.irurueta.algebra.AlgebraException - if there are numerical instabilities.

estimate

public static void estimate(Collection<GNSSMeasurement> measurements,
 double propagationInterval,
 GNSSEstimation previousEstimation,
 com.irurueta.algebra.Matrix previousCovariance,
 GNSSKalmanConfig config,
 GNSSEstimation updatedEstimation,
 com.irurueta.algebra.Matrix updatedCovariance)
                     throws com.irurueta.algebra.AlgebraException

Estimates the update of Kalman filter state and covariance matrix for a single epoch.

Parameters:

measurements - satellite measurements data.

propagationInterval - propagation interval expressed in seconds (s).

previousEstimation - previous GNSS estimates.

previousCovariance - previous Kalman filter error covariance matrix.

config - system configuration (usually obtained through calibration).

updatedEstimation - instance where updated GNSS estimate will be stored after executing this method.

updatedCovariance - instance where updated Kalman filter error covariance matrix will be stored.

Throws:

IllegalArgumentException - if provided previous covariance matrix is not 8x8.

com.irurueta.algebra.AlgebraException - if there are numerical instabilities.

convertTime

private static double convertTime(com.irurueta.units.Time time)

Converts time instance into a value expressed in seconds.

Parameters:

time - time instance to be converted.

Returns:

time value expressed in seconds.