agi.foundation.communications

(agi.foundation.communications-2024r2.jar)

Class PointScattererExtension

java.lang.Object

agi.foundation.infrastructure.DefinitionalObject

agi.foundation.infrastructure.ObjectExtension

agi.foundation.communications.PointScattererExtension

All Implemented Interfaces:

ISignalTransmissionService, IIdentifiableTransmitterService, IPointScattererService, ICloneWithContext, IEnumerateDependencies, IEquatableDefinition, IFreezable, IServiceProvider

Direct Known Subclasses:

TargetRadarCrossSectionExtension

public abstract class PointScattererExtension
extends ObjectExtension
implements IPointScattererService

An ObjectExtension which is used to model signal reflections using a single point scatterer model.

The PointScattererExtension is comprised of a collection of PointScattererFrequencyBand instances which cover the entire overall frequency band defined by MinimumFrequency (get) to MaximumFrequency (get). Each PointScattererFrequencyBand is configured with a ScatteringCoefficient. When evaluated, the PointScattererFrequencyBand which contains the frequency of the incident signal is used to compute the scattering coefficient which then is multiplied by the incident signal's power in order to determine how much power is in the reflected signal.

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	PointScattererExtension() Initializes a new instance.
protected	PointScattererExtension(double minimumFrequency, double maximumFrequency) Initializes a new instance.
protected	PointScattererExtension(double minimumFrequency, double maximumFrequency, ScatteringCoefficient scatteringCoefficient) Initializes a new instance.
protected	PointScattererExtension(PointScattererExtension existingInstance, CopyContext context) Initializes a new instance as a copy of an existing instance.
protected	PointScattererExtension(ScatteringCoefficient scatteringCoefficient) Initializes a new instance and sets the supplied ScatteringCoefficient as the first frequency band's scattering coefficient.

Method Summary

Modifier and Type	Method and Description
protected boolean	checkForSameDefinition(ObjectExtension other) Checks to determine if another instance has the same definition as this instance and returns true if it does.
protected abstract boolean	checkForSameDefinition(PointScattererExtension other) Checks to determine if another instance has the same definition as this instance and returns true if it does.
protected int	computeCurrentDefinitionHashCode() Computes a hash code based on the current properties of this object.
void	enumerateDependencies(DependencyEnumerator enumerator) Enumerates the dependencies of this object by calling DependencyEnumerator#enumerate(T) for each object that this object directly depends upon.
protected void	freezeAggregatedObjects() Called by DefinitionalObject.freeze() to also freeze any objects that are considered to be a part of this object.
PointScattererFrequencyBandCollection	getFrequencyBands() Gets the list of frequency bands.
abstract SignalIdentifier	getIdentifier() Gets the identifier for the signals scattered by this object.
Axes	getSignalTransmissionAxes() Gets the Axes associated with signal transmission.
SignalEvaluator	getSignalTransmissionEvaluator(EvaluatorGroup group, Vector reflectedVector, SignalPropagationGraph graph) Get an evaluator which can produce a reflected signal which is the incident signal multiplied by the scattering coefficient computed for the incident and reflected link geometry.

Methods inherited from class agi.foundation.infrastructure.ObjectExtension

checkForSameDefinition, getOwner, getService

Methods inherited from class agi.foundation.infrastructure.DefinitionalObject

areSameDefinition, areSameDefinition, areSameDefinition, areSameDefinition, areSameDefinition, clone, collectionItemsAreSameDefinition, collectionItemsAreSameDefinition, collectionItemsAreSameDefinition, dictionaryItemsAreSameDefinition, freeze, getCollectionHashCode, getCollectionHashCode, getCollectionHashCode, getDefinitionHashCode, getDefinitionHashCode, getDefinitionHashCode, getDefinitionHashCode, getDefinitionHashCode, getDefinitionHashCode, getDictionaryHashCode, getIsFrozen, isSameDefinition, throwIfFrozen

Methods inherited from class java.lang.Object

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

Constructor Detail

PointScattererExtension

protected PointScattererExtension()

Initializes a new instance.

This constructor will create an empty PointScattererFrequencyBandCollection with MinimumFrequency (get) set to the CommunicationsConstants.MinimumRfFrequency value and the MaximumFrequency (get) set to the CommunicationsConstants.MaximumRfFrequency value.

PointScattererExtension

protected PointScattererExtension(double minimumFrequency,
                                  double maximumFrequency)

Initializes a new instance.

This constructor will create an empty PointScattererFrequencyBandCollection with MinimumFrequency (get) set to the minimumFrequency parameter value and the MaximumFrequency (get) set to the maximumFrequency parameter value.

Parameters:

minimumFrequency - The minimum frequency for the overall frequency band of the collection.

maximumFrequency - The maximum frequency for the overall frequency band of the collection.

PointScattererExtension

protected PointScattererExtension(double minimumFrequency,
                                  double maximumFrequency,
                                  ScatteringCoefficient scatteringCoefficient)

Initializes a new instance.

This constructor will add a single PointScattererFrequencyBand into the frequency band collection with LowerFrequency (get) set to the minimumFrequency parameter value and with the scatteringCoefficient parameter set as the ScatteringCoefficient algorithm.

Parameters:

minimumFrequency - The minimum frequency for the overall frequency band of the collection.

maximumFrequency - The maximum frequency for the overall frequency band of the collection.

scatteringCoefficient - The scattering coefficient algorithm to be used by the first frequency band in the FrequencyBands (get) collection.

PointScattererExtension

protected PointScattererExtension(ScatteringCoefficient scatteringCoefficient)

Initializes a new instance and sets the supplied ScatteringCoefficient as the first frequency band's scattering coefficient.

This constructor will add a single PointScattererFrequencyBand into the frequency band collection with LowerFrequency (get) set to the CommunicationsConstants.MinimumRfFrequency value and with the scatteringCoefficient parameter set as the ScatteringCoefficient algorithm.

Parameters:

scatteringCoefficient - The scattering coefficient algorithm to be used by the first frequency band in the FrequencyBands (get) collection.

PointScattererExtension

protected PointScattererExtension(@Nonnull
                                  PointScattererExtension existingInstance,
                                  @Nonnull
                                  CopyContext context)

Initializes a new instance as a copy of an existing instance.

See ICloneWithContext.clone(CopyContext) for more information about how to implement this constructor in a derived class.

Parameters:

existingInstance - The existing instance to copy.

context - A CopyContext that controls the depth of the copy.

Throws:

ArgumentNullException - Thrown when existingInstance or context is null.

Method Detail

checkForSameDefinition

protected final boolean checkForSameDefinition(ObjectExtension other)

Checks to determine if another instance has the same definition as this instance and returns true if it does. Derived classes MUST override this method and check all new fields introduced by the derived class for definitional equivalence. It is NOT necessary to check base class fields because the base class will already have done that. When overriding this method, you should NOT call the base implementation because it will return false for all derived-class instances. Derived classes should check the type of other to preserve the symmetric nature of IEquatableDefinition.isSameDefinition(java.lang.Object).

Specified by:

checkForSameDefinition in class ObjectExtension

Parameters:

other - The other instance to compare to this one.

Returns:

true if the two objects are defined equivalently; otherwise false.

checkForSameDefinition

protected abstract boolean checkForSameDefinition(PointScattererExtension other)

Checks to determine if another instance has the same definition as this instance and returns true if it does. Derived classes MUST override this method and check all new fields introduced by the derived class for definitional equivalence. It is NOT necessary to check base class fields because the base class will already have done that. When overriding this method, you should NOT call the base implementation because it will return false for all derived-class instances. Derived classes should check the type of other to preserve the symmetric nature of IEquatableDefinition.isSameDefinition(java.lang.Object).

Parameters:

other - The other instance to compare to this one.

Returns:

true if the two objects are defined equivalently; otherwise false.

computeCurrentDefinitionHashCode

protected int computeCurrentDefinitionHashCode()

Computes a hash code based on the current properties of this object. Derived classes MUST override this method and compute a hash code that combines: a unique hash code seed, the base implementation result, and the hash codes of all new fields introduced by the derived class which are used in the PointScattererExtension.checkForSameDefinition(agi.foundation.infrastructure.ObjectExtension) method.

Overrides:

computeCurrentDefinitionHashCode in class ObjectExtension

Returns:

The computed hash code.

enumerateDependencies

public void enumerateDependencies(DependencyEnumerator enumerator)

Enumerates the dependencies of this object by calling DependencyEnumerator#enumerate(T) for each object that this object directly depends upon. Derived classes which contain additional dependencies MUST override this method, call the base implementation, and enumerate dependencies introduced by the derived class.

Specified by:

enumerateDependencies in interface IEnumerateDependencies

Overrides:

enumerateDependencies in class ObjectExtension

Parameters:

enumerator - The enumerator that is informed of the dependencies of this object.

freezeAggregatedObjects

protected void freezeAggregatedObjects()

Called by DefinitionalObject.freeze() to also freeze any objects that are considered to be a part of this object. Derived classes which contain additional aggregated objects MUST override this method, call the base implementation, and freeze aggregated objects introduced by the derived class. The objects that need to be frozen in this method are frequently created in this object's constructor and are not settable via properties.

Overrides:

freezeAggregatedObjects in class DefinitionalObject

getSignalTransmissionEvaluator

public final SignalEvaluator getSignalTransmissionEvaluator(EvaluatorGroup group,
                                                            Vector reflectedVector,
                                                            SignalPropagationGraph graph)

Get an evaluator which can produce a reflected signal which is the incident signal multiplied by the scattering coefficient computed for the incident and reflected link geometry.

This method can return an evaluator constructed in one of two different ways based on the type of SignalPropagationGraph which is passed as the graph parameter. If the graph parameter instance provides the ISignalPropagationPathService from a call to the instance GetService method, the evaluator will be constructed such that it pulls the incident signal from the link in the graph provided by the ISignalPropagationPathService.findLinkForReceiver(agi.foundation.IServiceProvider), where the receive node is the point scatterer extension's owning ExtensibleObject. If the graph supplies the ISignalPropagationPathService, but a call to FindLinkForReceiver returns null, an IllegalStateException will be thrown. If the graph parameter instance does not provide the ISignalPropagationPathService, then the evaluator returned will try to pull the incident signals for all links in the graph for which the point scatterer extension's owning ExtensibleObject is the receive node. If no links are found an IllegalStateException will be thrown.

Specified by:

getSignalTransmissionEvaluator in interface ISignalTransmissionService

Parameters:

group - The evaluator group in which to create the evaluator.

reflectedVector - The vector in the direction of the reflected signal with respect to the point scatterer.

graph - The graph of the communication links used to propagate signals.

Returns:

The evaluator which produces the reflected signal.

Throws:

PropertyInvalidException - Thrown if the FrequencyBands (get) collection has a count of 0. This exception is also thrown if the FrequencyBands (get) collection does not have a PointScattererFrequencyBand with a LowerFrequency (get) equal to the configured minimum frequency of the FrequencyBands (get) collection.

getSignalTransmissionAxes

public final Axes getSignalTransmissionAxes()

Gets the Axes associated with signal transmission.

Specified by:

getSignalTransmissionAxes in interface ISignalTransmissionService

Returns:

The Axes associated with signal transmission.

getIdentifier

public abstract SignalIdentifier getIdentifier()

Gets the identifier for the signals scattered by this object.

Specified by:

getIdentifier in interface IIdentifiableTransmitterService

getFrequencyBands

@Nonnull
public final PointScattererFrequencyBandCollection getFrequencyBands()

Gets the list of frequency bands.