ptolemy.domains.wireless.lib
Class PowerLossChannel
java.lang.Object
ptolemy.kernel.util.NamedObj
ptolemy.kernel.InstantiableNamedObj
ptolemy.kernel.Entity
ptolemy.kernel.ComponentEntity
ptolemy.actor.AtomicActor
ptolemy.actor.TypedAtomicActor
ptolemy.domains.wireless.kernel.AtomicWirelessChannel
ptolemy.domains.wireless.lib.ErasureChannel
ptolemy.domains.wireless.lib.DelayChannel
ptolemy.domains.wireless.lib.LimitedRangeChannel
ptolemy.domains.wireless.lib.PowerLossChannel
- All Implemented Interfaces:
- java.io.Serializable, java.lang.Cloneable, Actor, Executable, FiringsRecordable, Initializable, TypedActor, ChannelListener, PropertyTransformer, WirelessChannel, Changeable, Debuggable, DebugListener, Derivable, Instantiable, ModelErrorHandler, MoMLExportable, Moveable, Nameable, ValueListener
public class PowerLossChannel
- extends LimitedRangeChannel
This is a model of a wireless channel with a specified power propagation
formula. The power propagation is given as an expression that is evaluated
and then multiplied by the power field of the transmit properties before
delivery to the receiver. For convenience, a variable named "distance"
is available and equal to the distance between the transmitter and the
receiver when the power propagation formula is evaluated. Thus, the
expression can depend on this distance. The value of the power field should
be interpreted as power at the transmitter but power density at the receiver.
A receiver may multiply the power density with its efficiency and an
area(typically the antenna area). A receiver can then use the resulting
power to compare against a detectable threshold, or to determine
signal-to-interference ratio, for example.
The default value of powerPropagationFactor is
1.0 / (4 * PI * distance * distance).
This assumes that the transmit power is uniformly distributed
on a sphere of radius distance. The result of multiplying
this by a transmit power is a power density (power per unit area).
The receiver should multiply this power density by the area of the
sensor it uses to capture the energy (such as antenna area) and
also an efficiency factor which represents how effectively it capture
the energy.
The power field of the transmit properties can be supplied by
the transmitter as a record with a power field of type double.
The default value provided by this channel is Infinity, which when
multiplied by any positive constant will yield Infinity, which
presumably will be above any threshold. Thus, the default behavior
is to encounter no power loss and no limits to communication due
to power.
In addition, this channel can have a specified limited transmission
range. If a transmission range less than Infinity (the default)
is specified, then receivers outside the specified range will
not be notified of transmission, irrespective of power loss.
The transmission range can be specified in one of two ways.
Either it is the value of the range field in the
defaultProperties parameter (a record) of this
channel, or it is provided by the transmitter on each call to
transmit() as a property argument. To use the latter mechanism,
it is necessary that the property token be an instance of RecordToken
with a field named "range" that can be converted to a double
(i.e., it can be a double, an int, or a byte).
The default value for range is Infinity, which
indicates that by default, there is no range limit.
Any receiver that is within the specified range when transmit()
is called will receive the transmission, unless the lossProbability
parameter is set to greater than zero.
- Since:
- Ptolemy II 4.0
- Version:
- $Id: PowerLossChannel.java 57040 2010-01-27 20:52:32Z cxh $
- Author:
- Edward A. Lee
- See Also:
- Serialized Form
- Accepted Rating:
- Proposed Rating:
| Fields inherited from class ptolemy.kernel.util.NamedObj |
_changeListeners, _changeLock, _changeRequests, _debugging, _debugListeners, _elementName, _isPersistent, _verbose, _workspace, ATTRIBUTES, CLASSNAME, COMPLETE, CONTENTS, DEEP, FULLNAME, LINKS |
| Methods inherited from class ptolemy.domains.wireless.kernel.AtomicWirelessChannel |
_distanceBetween, _locationOf, _receiversInRange, addChannelListener, channelNotify, getChannelPort, listeningInputPorts, listeningOutputPorts, preinitialize, registerPropertyTransformer, removeChannelListener, sendingInputPorts, sendingOutputPorts, transmit, unregisterPropertyTransformer |
| Methods inherited from class ptolemy.actor.AtomicActor |
_actorFiring, _actorFiring, addActorFiringListener, addInitializable, connectionsChanged, createReceivers, declareDelayDependency, getCausalityInterface, getDirector, getExecutiveDirector, getManager, inputPortList, isFireFunctional, isStrict, iterate, newReceiver, outputPortList, postfire, prefire, pruneDependencies, recordFiring, removeActorFiringListener, removeDependency, removeInitializable, setContainer, stop, stopFire, terminate, wrapup |
| Methods inherited from class ptolemy.kernel.ComponentEntity |
_adjustDeferrals, _checkContainer, _getContainedObject, _propagateExistence, getContainer, instantiate, isAtomic, isOpaque, moveDown, moveToFirst, moveToIndex, moveToLast, moveUp, propagateExistence, setName |
| Methods inherited from class ptolemy.kernel.Entity |
_description, _exportMoMLContents, _removePort, _validateSettables, connectedPortList, connectedPorts, containedObjectsIterator, getAttribute, getPort, getPorts, linkedRelationList, linkedRelations, portList, removeAllPorts, setClassDefinition, uniqueName |
| Methods inherited from class ptolemy.kernel.util.NamedObj |
_addAttribute, _adjustOverride, _attachText, _cloneFixAttributeFields, _debug, _debug, _debug, _debug, _debug, _getIndentPrefix, _isMoMLSuppressed, _markContentsDerived, _propagateValue, _recordDecoratedAttributes, _removeAttribute, _splitName, _stripNumericSuffix, addChangeListener, addDebugListener, attributeList, attributeList, deepContains, depthInHierarchy, description, description, event, executeChangeRequests, exportMoML, exportMoML, exportMoML, exportMoML, exportMoMLPlain, getAttribute, getAttributes, getChangeListeners, getClassName, getDecoratorAttribute, getDecoratorAttributes, getDerivedLevel, getDerivedList, getDisplayName, getFullName, getModelErrorHandler, getName, getName, getSource, handleModelError, isDeferringChangeRequests, isOverridden, isPersistent, lazyContainedObjectsIterator, message, propagateValue, propagateValues, removeChangeListener, removeDebugListener, requestChange, setClassName, setDeferringChangeRequests, setDerivedLevel, setDisplayName, setModelErrorHandler, setPersistent, setSource, sortContainedObjects, toplevel, toString, validateSettables, workspace |
| Methods inherited from class java.lang.Object |
equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait |
powerPropagationFactor
public Parameter powerPropagationFactor
- The default formula for the power loss factor.
This value, when multiplied by the transmit power, yields
the power density (per unit area) at a receiver. It can
be an expression that depends on a variable "distance,"
which has the value of the distance between a transmitter
and receiver when this parameter is evaluated. This is
a double that defaults to
"1.0 / (distance * distance))".
PowerLossChannel
public PowerLossChannel(CompositeEntity container,
java.lang.String name)
throws IllegalActionException,
NameDuplicationException
- Construct a channel with the given name and container.
The container argument must not be null, or a
NullPointerException will be thrown. If the name argument
is null, then the name is set to the empty string.
- Parameters:
container - The container.name - The name of the channel.
- Throws:
IllegalActionException - If the container is incompatible.
NameDuplicationException - If the name coincides with
an actor already in the container.
transformProperties
public RecordToken transformProperties(RecordToken properties,
WirelessIOPort source,
WirelessIOPort destination)
throws IllegalActionException
- Transform the properties to take into account channel losses,
noise, etc., for transmission between the specified sender
and the specified receiver. In this base class, the
specified properties are merged with the defaultProperties
so that the resulting properties contain at least all the
fields of the defaultProperties.
- Specified by:
transformProperties in interface PropertyTransformer- Overrides:
transformProperties in class AtomicWirelessChannel
- Parameters:
properties - The transmit properties.source - The sending port.destination - The receiving port.
- Returns:
- The transformed properties.
- Throws:
IllegalActionException - If the properties cannot
be transformed. Not thrown in this base class.- See Also:
AtomicWirelessChannel.registerPropertyTransformer(PropertyTransformer, WirelessIOPort)