Base class for the 3GPP channel condition models. More...

#include "channel-condition-model.h"

Inheritance diagram for ns3::ThreeGppChannelConditionModel:

Collaboration diagram for ns3::ThreeGppChannelConditionModel:

Classes
struct	Item
	Struct to store the channel condition in the m_channelConditionMap. More...

Public Member Functions
	ThreeGppChannelConditionModel ()
	Constructor for the ThreeGppRmaChannelConditionModel class.

	~ThreeGppChannelConditionModel () override
	Destructor for the ThreeGppRmaChannelConditionModel class.

int64_t	AssignStreams (int64_t stream) override
	If this model uses objects of type RandomVariableStream, set the stream numbers to the integers starting with the offset 'stream'.

Ptr< ChannelCondition >	GetChannelCondition (Ptr< const MobilityModel > a, Ptr< const MobilityModel > b) const override
	Retrieve the condition of the channel between a and b.

Public Member Functions inherited from ns3::ChannelConditionModel
	ChannelConditionModel ()
	Constructor for the ChannelConditionModel class.

	ChannelConditionModel (const ChannelConditionModel &)=delete

	~ChannelConditionModel () override
	Destructor for the ChannelConditionModel class.

virtual int64_t	AssignStreams (int64_t stream)=0
	If this model uses objects of type RandomVariableStream, set the stream numbers to the integers starting with the offset 'stream'.

virtual Ptr< ChannelCondition >	GetChannelCondition (Ptr< const MobilityModel > a, Ptr< const MobilityModel > b) const =0
	Computes the condition of the channel between a and b.

ChannelConditionModel &	operator= (const ChannelConditionModel &)=delete

Public Member Functions inherited from ns3::Object
	Object ()
	Constructor.

	~Object () override
	Destructor.

void	AggregateObject (Ptr< Object > other)
	Aggregate two Objects together.

void	Dispose ()
	Dispose of this Object.

AggregateIterator	GetAggregateIterator () const
	Get an iterator to the Objects aggregated to this one.

TypeId	GetInstanceTypeId () const override
	Get the most derived TypeId for this Object.

template<typename T >
Ptr< T >	GetObject () const
	Get a pointer to the requested aggregated Object.

template<>
Ptr< Object >	GetObject () const
	Specialization of () for objects of type ns3::Object.

template<typename T >
Ptr< T >	GetObject (TypeId tid) const
	Get a pointer to the requested aggregated Object by TypeId.

template<>
Ptr< Object >	GetObject (TypeId tid) const
	Specialization of (TypeId tid) for objects of type ns3::Object.

void	Initialize ()
	Invoke DoInitialize on all Objects aggregated to this one.

bool	IsInitialized () const
	Check if the object has been initialized.

void	UnidirectionalAggregateObject (Ptr< Object > other)
	Aggregate an Object to another Object.

Public Member Functions inherited from ns3::SimpleRefCount< Object, ObjectBase, ObjectDeleter >
	SimpleRefCount ()
	Default constructor.

	SimpleRefCount (const SimpleRefCount &o)
	Copy constructor.

uint32_t	GetReferenceCount () const
	Get the reference count of the object.

SimpleRefCount &	operator= (const SimpleRefCount &o)
	Assignment operator.

void	Ref () const
	Increment the reference count.

void	Unref () const
	Decrement the reference count.

Public Member Functions inherited from ns3::ObjectBase
virtual	~ObjectBase ()
	Virtual destructor.

void	GetAttribute (std::string name, AttributeValue &value) const
	Get the value of an attribute, raising fatal errors if unsuccessful.

bool	GetAttributeFailSafe (std::string name, AttributeValue &value) const
	Get the value of an attribute without raising errors.

virtual TypeId	GetInstanceTypeId () const =0
	Get the most derived TypeId for this Object.

void	SetAttribute (std::string name, const AttributeValue &value)
	Set a single attribute, raising fatal errors if unsuccessful.

bool	SetAttributeFailSafe (std::string name, const AttributeValue &value)
	Set a single attribute without raising errors.

bool	TraceConnect (std::string name, std::string context, const CallbackBase &cb)
	Connect a TraceSource to a Callback with a context.

bool	TraceConnectWithoutContext (std::string name, const CallbackBase &cb)
	Connect a TraceSource to a Callback without a context.

bool	TraceDisconnect (std::string name, std::string context, const CallbackBase &cb)
	Disconnect from a TraceSource a Callback previously connected with a context.

bool	TraceDisconnectWithoutContext (std::string name, const CallbackBase &cb)
	Disconnect from a TraceSource a Callback previously connected without a context.

Static Public Member Functions
static TypeId	GetTypeId ()
	Get the type ID.

Static Public Member Functions inherited from ns3::ChannelConditionModel
static TypeId	GetTypeId ()
	Get the type ID.

Static Public Member Functions inherited from ns3::Object
static TypeId	GetTypeId ()
	Register this type.

Static Public Member Functions inherited from ns3::ObjectBase
static TypeId	GetTypeId ()
	Get the type ID.

Protected Types
enum	VehicleDensity { LOW , MEDIUM , HIGH , INVALID }
	Determine the density of vehicles in a V2V scenario. More...

Protected Member Functions
void	DoDispose () override
	Destructor implementation.

Protected Member Functions inherited from ns3::Object
	Object (const Object &o)
	Copy an Object.

virtual void	DoDispose ()
	Destructor implementation.

virtual void	DoInitialize ()
	Initialize() implementation.

virtual void	NotifyNewAggregate ()
	Notify all Objects aggregated to this one of a new Object being aggregated.

Protected Member Functions inherited from ns3::ObjectBase
void	ConstructSelf (const AttributeConstructionList &attributes)
	Complete construction of ObjectBase; invoked by derived classes.

virtual void	NotifyConstructionCompleted ()
	Notifier called once the ObjectBase is fully constructed.

Static Protected Member Functions
static double	Calculate2dDistance (const Vector &a, const Vector &b)
	Computes the 2D distance between two 3D vectors.

Protected Attributes
Ptr< UniformRandomVariable >	m_uniformVar
	uniform random variable

Private Member Functions
Ptr< ChannelCondition >	ComputeChannelCondition (Ptr< const MobilityModel > a, Ptr< const MobilityModel > b) const
	This method computes the channel condition based on a probabilistic model that is specific for the scenario of interest.

virtual ChannelCondition::O2iConditionValue	ComputeO2i (Ptr< const MobilityModel > a, Ptr< const MobilityModel > b) const
	Determines whether the channel condition is O2I or O2O.

virtual double	ComputePlos (Ptr< const MobilityModel > a, Ptr< const MobilityModel > b) const =0
	Compute the LOS probability.

virtual double	ComputePnlos (Ptr< const MobilityModel > a, Ptr< const MobilityModel > b) const
	Compute the NLOS probability.

Static Private Member Functions
static uint32_t	GetKey (Ptr< const MobilityModel > a, Ptr< const MobilityModel > b)
	Returns a unique and reciprocal key for the channel between a and b.

Private Attributes
std::unordered_map< uint32_t, Item >	m_channelConditionMap
	map to store the channel conditions

bool	m_linkO2iConditionToAntennaHeight
	the indicator that determines whether the O2I/O2O condition is determined based on the UE height

double	m_o2iLowLossThreshold {0}
	the threshold for determining what is the ratio of low - high O2I building penetration losses

double	m_o2iThreshold
	the threshold for determining what is the ratio of channels with O2I

Ptr< UniformRandomVariable >	m_uniformO2iLowHighLossVar
	a uniform random variable for the calculation of the low/high losses, see TR38.901 Table 7.4.3-2

Ptr< UniformRandomVariable >	m_uniformVarO2i
	uniform random variable that is used for the generation of the O2i conditions

Time	m_updatePeriod
	the update period for the channel condition

Additional Inherited Members
Related Functions inherited from ns3::ObjectBase
static TypeId	GetObjectIid ()
	Ensure the TypeId for ObjectBase gets fully configured to anchor the inheritance tree properly.

Detailed Description

Base class for the 3GPP channel condition models.

Config Paths

ns3::ThreeGppChannelConditionModel is accessible through the following paths with Config::Set and Config::Connect:

"/NodeList/[i]/DeviceList/[i]/$ns3::WifiNetDevice/Channel/$ns3::SpectrumChannel/PropagationLossModel/$ns3::ThreeGppPropagationLossModel/ChannelConditionModel/$ns3::ThreeGppChannelConditionModel"
"/NodeList/[i]/DeviceList/[i]/$ns3::WifiNetDevice/Channel/$ns3::YansWifiChannel/PropagationLossModel/$ns3::ThreeGppPropagationLossModel/ChannelConditionModel/$ns3::ThreeGppChannelConditionModel"
"/NodeList/[i]/DeviceList/[i]/$ns3::WifiNetDevice/Phy/Channel/$ns3::SpectrumChannel/PropagationLossModel/$ns3::ThreeGppPropagationLossModel/ChannelConditionModel/$ns3::ThreeGppChannelConditionModel"
"/NodeList/[i]/DeviceList/[i]/$ns3::WifiNetDevice/Phy/Channel/$ns3::YansWifiChannel/PropagationLossModel/$ns3::ThreeGppPropagationLossModel/ChannelConditionModel/$ns3::ThreeGppChannelConditionModel"
"/NodeList/[i]/DeviceList/[i]/$ns3::WifiNetDevice/Phys/[i]/Channel/$ns3::SpectrumChannel/PropagationLossModel/$ns3::ThreeGppPropagationLossModel/ChannelConditionModel/$ns3::ThreeGppChannelConditionModel"
"/NodeList/[i]/DeviceList/[i]/$ns3::WifiNetDevice/Phys/[i]/Channel/$ns3::YansWifiChannel/PropagationLossModel/$ns3::ThreeGppPropagationLossModel/ChannelConditionModel/$ns3::ThreeGppChannelConditionModel"
"/NodeList/[i]/DeviceList/[i]/$ns3::LrWpanNetDevice/Channel/PropagationLossModel/$ns3::ThreeGppPropagationLossModel/ChannelConditionModel/$ns3::ThreeGppChannelConditionModel"
"/ChannelList/[i]/$ns3::SpectrumChannel/PropagationLossModel/$ns3::ThreeGppPropagationLossModel/ChannelConditionModel/$ns3::ThreeGppChannelConditionModel"
"/ChannelList/[i]/$ns3::YansWifiChannel/PropagationLossModel/$ns3::ThreeGppPropagationLossModel/ChannelConditionModel/$ns3::ThreeGppChannelConditionModel"

Attributes

LinkO2iConditionToAntennaHeight: Specifies whether the O2I condition will be determined based on the UE height, i.e. if the UE height is 1.5 then it is O2O, otherwise it is O2I.
- Set with class: ns3::BooleanValue
- Underlying type: bool
- Initial value: false
- Flags: constructwriteread
O2iLowLossThreshold: Specifies what will be the ratio of O2I low - high penetration losses. Default value is 1.0 meaning thatall losses will be low
- Set with class: ns3::DoubleValue
- Underlying type: double 0:1
- Initial value: 1
- Flags: constructwriteread
O2iThreshold: Specifies what will be the ratio of O2I channel conditions. Default value is 0 that corresponds to 0 O2I losses.
- Set with class: ns3::DoubleValue
- Underlying type: double 0:1
- Initial value: 0
- Flags: constructwriteread
UpdatePeriod: Specifies the time period after which the channel condition is recomputed. If set to 0, the channel condition is never updated.
- Set with class: ns3::TimeValue
- Underlying type: Time +9.22337e+18ns:+9.22337e+18ns
- Initial value: +0ns
- Flags: constructwriteread

No TraceSources are defined for this type.
Size of this type is 168 bytes (on a 64-bit architecture).

Definition at line 441 of file channel-condition-model.h.

Member Enumeration Documentation

◆ VehicleDensity

enum ns3::ThreeGppChannelConditionModel::VehicleDensity

protected

Determine the density of vehicles in a V2V scenario.

Enumerator
LOW
MEDIUM
HIGH
INVALID

Definition at line 492 of file channel-condition-model.h.

Constructor & Destructor Documentation

◆ ThreeGppChannelConditionModel()

ns3::ThreeGppChannelConditionModel::ThreeGppChannelConditionModel ( )

Constructor for the ThreeGppRmaChannelConditionModel class.

Definition at line 337 of file channel-condition-model.cc.

References m_uniformO2iLowHighLossVar, m_uniformVar, m_uniformVarO2i, and ns3::ObjectBase::SetAttribute().

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◆ ~ThreeGppChannelConditionModel()

ns3::ThreeGppChannelConditionModel::~ThreeGppChannelConditionModel ( )

override

Destructor for the ThreeGppRmaChannelConditionModel class.

Definition at line 348 of file channel-condition-model.cc.

Member Function Documentation

◆ AssignStreams()

int64_t ns3::ThreeGppChannelConditionModel::AssignStreams ( int64_t stream )

overridevirtual

If this model uses objects of type RandomVariableStream, set the stream numbers to the integers starting with the offset 'stream'.

Return the number of streams (possibly zero) that have been assigned.

Parameters

stream the offset used to set the stream numbers

Returns: the number of stream indices assigned by this model

Implements ns3::ChannelConditionModel.

Definition at line 507 of file channel-condition-model.cc.

References m_uniformO2iLowHighLossVar, m_uniformVar, m_uniformVarO2i, and ns3::RandomVariableStream::SetStream().

Referenced by ThreeGppV2vUrbanLosNlosvChCondModelTestCase::DoRun(), ThreeGppV2vHighwayLosNlosvChCondModelTestCase::DoRun(), V2vUrbanProbChCondModelTestCase::DoRun(), and V2vHighwayProbChCondModelTestCase::DoRun().

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◆ Calculate2dDistance()

double ns3::ThreeGppChannelConditionModel::Calculate2dDistance	(	const Vector &	a,
		const Vector &	b
	)

staticprotected

Computes the 2D distance between two 3D vectors.

Parameters

a	the first 3D vector
b	the second 3D vector

Returns: the 2D distance between a and b

Definition at line 517 of file channel-condition-model.cc.

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◆ ComputeChannelCondition()

Ptr< ChannelCondition > ns3::ThreeGppChannelConditionModel::ComputeChannelCondition	(	Ptr< const MobilityModel >	a,
		Ptr< const MobilityModel >	b
	)		const

private

This method computes the channel condition based on a probabilistic model that is specific for the scenario of interest.

Parameters

a	tx mobility model
b	rx mobility model

Returns: the channel condition

Definition at line 441 of file channel-condition-model.cc.

References ComputeO2i(), ComputePlos(), ComputePnlos(), ns3::UniformRandomVariable::GetValue(), ns3::ChannelCondition::HIGH, ns3::ChannelCondition::LOS, ns3::ChannelCondition::LOW, m_o2iLowLossThreshold, m_uniformO2iLowHighLossVar, m_uniformVar, ns3::ChannelCondition::NLOS, ns3::ChannelCondition::NLOSv, NS_LOG_DEBUG, NS_LOG_FUNCTION, and ns3::ChannelCondition::O2I.

Referenced by GetChannelCondition().

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◆ ComputeO2i()

ChannelCondition::O2iConditionValue ns3::ThreeGppChannelConditionModel::ComputeO2i	(	Ptr< const MobilityModel >	a,
		Ptr< const MobilityModel >	b
	)		const

privatevirtual

Determines whether the channel condition is O2I or O2O.

Parameters

a	tx mobility model
b	rx mobility model

Returns: the O2I channelcondition

Definition at line 409 of file channel-condition-model.cc.

References ns3::UniformRandomVariable::GetValue(), m_linkO2iConditionToAntennaHeight, m_o2iThreshold, m_uniformVarO2i, NS_LOG_INFO, ns3::ChannelCondition::O2I, and ns3::ChannelCondition::O2O.

Referenced by ComputeChannelCondition().

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◆ ComputePlos()

virtual double ns3::ThreeGppChannelConditionModel::ComputePlos	(	Ptr< const MobilityModel >	a,
		Ptr< const MobilityModel >	b
	)		const

privatepure virtual

Compute the LOS probability.

Parameters

a	tx mobility model
b	rx mobility model

Returns: the LOS probability

Implemented in ns3::ThreeGppV2vUrbanChannelConditionModel, ns3::ThreeGppV2vHighwayChannelConditionModel, ns3::ThreeGppRmaChannelConditionModel, ns3::ThreeGppUmaChannelConditionModel, ns3::ThreeGppUmiStreetCanyonChannelConditionModel, ns3::ThreeGppIndoorMixedOfficeChannelConditionModel, ns3::ThreeGppIndoorOpenOfficeChannelConditionModel, ns3::ProbabilisticV2vUrbanChannelConditionModel, and ns3::ProbabilisticV2vHighwayChannelConditionModel.

Referenced by ComputeChannelCondition(), and ComputePnlos().

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◆ ComputePnlos()

double ns3::ThreeGppChannelConditionModel::ComputePnlos	(	Ptr< const MobilityModel >	a,
		Ptr< const MobilityModel >	b
	)		const

privatevirtual

Compute the NLOS probability.

By default returns 1 - PLOS

Parameters

a	tx mobility model
b	rx mobility model

Returns: the LOS probability

Reimplemented in ns3::ThreeGppV2vUrbanChannelConditionModel, ns3::ThreeGppV2vHighwayChannelConditionModel, ns3::ProbabilisticV2vUrbanChannelConditionModel, and ns3::ProbabilisticV2vHighwayChannelConditionModel.

Definition at line 498 of file channel-condition-model.cc.

References ComputePlos(), and NS_LOG_FUNCTION.

Referenced by ComputeChannelCondition().

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◆ DoDispose()

void ns3::ThreeGppChannelConditionModel::DoDispose ( )

overrideprotectedvirtual

Destructor implementation.

This method is called by Dispose() or by the Object's destructor, whichever comes first.

Subclasses are expected to implement their real destruction code in an overridden version of this method and chain up to their parent's implementation once they are done. i.e, for simplicity, the destructor of every subclass should be empty and its content should be moved to the associated DoDispose() method.

It is safe to call GetObject() from within this method.

Reimplemented from ns3::Object.

Definition at line 353 of file channel-condition-model.cc.

References m_channelConditionMap, m_updatePeriod, and ns3::Seconds().

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◆ GetChannelCondition()

Ptr< ChannelCondition > ns3::ThreeGppChannelConditionModel::GetChannelCondition	(	Ptr< const MobilityModel >	a,
		Ptr< const MobilityModel >	b
	)		const

overridevirtual

Retrieve the condition of the channel between a and b.

If the channel condition does not exists, the method computes it by calling ComputeChannelCondition and stores it in a local cache, that will be updated following the "UpdatePeriod" parameter.

Parameters

a	mobility model
b	mobility model

Returns: the condition of the channel between a and b

Implements ns3::ChannelConditionModel.

Definition at line 360 of file channel-condition-model.cc.

References ComputeChannelCondition(), GetKey(), ns3::Time::IsZero(), m_channelConditionMap, ns3::ThreeGppChannelConditionModel::Item::m_condition, ns3::ThreeGppChannelConditionModel::Item::m_generatedTime, m_updatePeriod, ns3::Simulator::Now(), and NS_LOG_DEBUG.

Referenced by ThreeGppV2vUrbanLosNlosvChCondModelTestCase::EvaluateChannelCondition(), ThreeGppV2vHighwayLosNlosvChCondModelTestCase::EvaluateChannelCondition(), ThreeGppChannelConditionModelTestCase::EvaluateChannelCondition(), V2vUrbanProbChCondModelTestCase::EvaluateChannelCondition(), and V2vHighwayProbChCondModelTestCase::EvaluateChannelCondition().

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◆ GetKey()

uint32_t ns3::ThreeGppChannelConditionModel::GetKey	(	Ptr< const MobilityModel >	a,
		Ptr< const MobilityModel >	b
	)

staticprivate

Returns a unique and reciprocal key for the channel between a and b.

Parameters

a	tx mobility model
b	rx mobility model

Returns: channel key

Definition at line 527 of file channel-condition-model.cc.

References ns3::Node::GetId().

Referenced by GetChannelCondition().

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◆ GetTypeId()

TypeId ns3::ThreeGppChannelConditionModel::GetTypeId ( )

static

Get the type ID.

Returns: the object TypeId

Definition at line 299 of file channel-condition-model.cc.

References m_linkO2iConditionToAntennaHeight, m_o2iLowLossThreshold, m_o2iThreshold, m_updatePeriod, ns3::MakeBooleanAccessor(), ns3::MakeBooleanChecker(), ns3::MakeDoubleAccessor(), ns3::MakeTimeAccessor(), ns3::MakeTimeChecker(), ns3::MilliSeconds(), and ns3::TypeId::SetParent().

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Member Data Documentation

◆ m_channelConditionMap

std::unordered_map<uint32_t, Item> ns3::ThreeGppChannelConditionModel::m_channelConditionMap

private

map to store the channel conditions

Definition at line 568 of file channel-condition-model.h.

Referenced by DoDispose(), and GetChannelCondition().

◆ m_linkO2iConditionToAntennaHeight

bool ns3::ThreeGppChannelConditionModel::m_linkO2iConditionToAntennaHeight

private

Initial value:

{

false}

the indicator that determines whether the O2I/O2O condition is determined based on the UE height

Definition at line 575 of file channel-condition-model.h.

Referenced by ComputeO2i(), and GetTypeId().

◆ m_o2iLowLossThreshold

double ns3::ThreeGppChannelConditionModel::m_o2iLowLossThreshold {0}

private

the threshold for determining what is the ratio of low - high O2I building penetration losses

Definition at line 573 of file channel-condition-model.h.

Referenced by ComputeChannelCondition(), and GetTypeId().

◆ m_o2iThreshold

double ns3::ThreeGppChannelConditionModel::m_o2iThreshold

private

Initial value:

{

0}

the threshold for determining what is the ratio of channels with O2I

Definition at line 571 of file channel-condition-model.h.

Referenced by ComputeO2i(), and GetTypeId().

◆ m_uniformO2iLowHighLossVar

Ptr<UniformRandomVariable> ns3::ThreeGppChannelConditionModel::m_uniformO2iLowHighLossVar

private

a uniform random variable for the calculation of the low/high losses, see TR38.901 Table 7.4.3-2

Definition at line 581 of file channel-condition-model.h.

Referenced by ThreeGppChannelConditionModel(), AssignStreams(), and ComputeChannelCondition().

◆ m_uniformVar

Ptr<UniformRandomVariable> ns3::ThreeGppChannelConditionModel::m_uniformVar

protected

uniform random variable

Definition at line 508 of file channel-condition-model.h.

Referenced by ThreeGppChannelConditionModel(), AssignStreams(), and ComputeChannelCondition().

◆ m_uniformVarO2i

Ptr<UniformRandomVariable> ns3::ThreeGppChannelConditionModel::m_uniformVarO2i

private

uniform random variable that is used for the generation of the O2i conditions

Definition at line 578 of file channel-condition-model.h.

Referenced by ThreeGppChannelConditionModel(), AssignStreams(), and ComputeO2i().

◆ m_updatePeriod

Time ns3::ThreeGppChannelConditionModel::m_updatePeriod

private

the update period for the channel condition

Definition at line 569 of file channel-condition-model.h.

Referenced by DoDispose(), GetChannelCondition(), and GetTypeId().

The documentation for this class was generated from the following files:

src/propagation/model/channel-condition-model.h
src/propagation/model/channel-condition-model.cc

Classes

Public Member Functions

Static Public Member Functions

Protected Types

Protected Member Functions

Static Protected Member Functions

Protected Attributes

Private Member Functions

Static Private Member Functions

Private Attributes

Additional Inherited Members

Detailed Description

Config Paths

Attributes

Member Enumeration Documentation

◆ VehicleDensity

Constructor & Destructor Documentation

◆ ThreeGppChannelConditionModel()

◆ ~ThreeGppChannelConditionModel()

Member Function Documentation

◆ AssignStreams()

◆ Calculate2dDistance()

◆ ComputeChannelCondition()

◆ ComputeO2i()

◆ ComputePlos()

◆ ComputePnlos()

◆ DoDispose()

◆ GetChannelCondition()

◆ GetKey()

◆ GetTypeId()

Member Data Documentation

◆ m_channelConditionMap

◆ m_linkO2iConditionToAntennaHeight

◆ m_o2iLowLossThreshold

◆ m_o2iThreshold

◆ m_uniformO2iLowHighLossVar

◆ m_uniformVar

◆ m_uniformVarO2i

◆ m_updatePeriod