a Two-Ray Ground propagation loss model ported from NS2 More...

#include <propagation-loss-model.h>

Inheritance diagram for ns3::TwoRayGroundPropagationLossModel:

Collaboration diagram for ns3::TwoRayGroundPropagationLossModel:

Public Member Functions
	TwoRayGroundPropagationLossModel ()
double	GetLambda (void) const
double	GetMinDistance (void) const
double	GetSystemLoss (void) const
void	SetHeightAboveZ (double heightAboveZ)
void	SetLambda (double frequency, double speed)
void	SetLambda (double lambda)
void	SetMinDistance (double minDistance)
void	SetSystemLoss (double systemLoss)
Public Member Functions inherited from ns3::PropagationLossModel
	PropagationLossModel ()
virtual	~PropagationLossModel ()
int64_t	AssignStreams (int64_t stream)
double	CalcRxPower (double txPowerDbm, Ptr< MobilityModel > a, Ptr< MobilityModel > b) const
Ptr< PropagationLossModel >	GetNext ()
	Gets the next PropagationLossModel in the chain of loss models that act on the signal.
void	SetNext (Ptr< PropagationLossModel > next)
	Enables a chain of loss models to act on the signal.
Public Member Functions inherited from ns3::Object
	Object ()
virtual	~Object ()
void	AggregateObject (Ptr< Object > other)
void	Dispose (void)
AggregateIterator	GetAggregateIterator (void) const
virtual TypeId	GetInstanceTypeId (void) const
template<typename T >
Ptr< T >	GetObject (void) const
template<typename T >
Ptr< T >	GetObject (TypeId tid) const
void	Start (void)
Public Member Functions inherited from ns3::SimpleRefCount< Object, ObjectBase, ObjectDeleter >
	SimpleRefCount ()
	SimpleRefCount (const SimpleRefCount &o)
uint32_t	GetReferenceCount (void) const
SimpleRefCount &	operator= (const SimpleRefCount &o)
void	Ref (void) const
void	Unref (void) const
Public Member Functions inherited from ns3::ObjectBase
virtual	~ObjectBase ()
void	GetAttribute (std::string name, AttributeValue &value) const
bool	GetAttributeFailSafe (std::string name, AttributeValue &attribute) const
void	SetAttribute (std::string name, const AttributeValue &value)
bool	SetAttributeFailSafe (std::string name, const AttributeValue &value)
bool	TraceConnect (std::string name, std::string context, const CallbackBase &cb)
bool	TraceConnectWithoutContext (std::string name, const CallbackBase &cb)
bool	TraceDisconnect (std::string name, std::string context, const CallbackBase &cb)
bool	TraceDisconnectWithoutContext (std::string name, const CallbackBase &cb)

Static Public Member Functions
static TypeId	GetTypeId (void)
	This method returns the TypeId associated to ns3::TwoRayGroundPropagationLossModel.

Private Member Functions
	TwoRayGroundPropagationLossModel (const TwoRayGroundPropagationLossModel &o)
double	DbmFromW (double w) const
double	DbmToW (double dbm) const
virtual int64_t	DoAssignStreams (int64_t stream)
virtual double	DoCalcRxPower (double txPowerDbm, Ptr< MobilityModel > a, Ptr< MobilityModel > b) const
TwoRayGroundPropagationLossModel &	operator= (const TwoRayGroundPropagationLossModel &o)

Private Attributes
double	m_heightAboveZ
double	m_lambda
double	m_minDistance
double	m_systemLoss

Static Private Attributes
static const double	PI = 3.14159265358979323846

Additional Inherited Members
Protected Member Functions inherited from ns3::Object
	Object (const Object &o)
virtual void	DoDispose (void)
virtual void	DoStart (void)
virtual void	NotifyNewAggregate (void)

Detailed Description

a Two-Ray Ground propagation loss model ported from NS2

Two-ray ground reflection model.

$Pr = \frac{Pt * Gt * Gr * (ht^2 * hr^2)}{d^4 * L}$

The original equation in Rappaport's book assumes L = 1. To be consistent with the free space equation, L is added here.

Ht and Hr are set at the respective nodes z coordinate plus a model parameter set via SetHeightAboveZ.

The two-ray model does not give a good result for short distances, due to the oscillation caused by constructive and destructive combination of the two rays. Instead the Friis free-space model is used for small distances.

The crossover distance, below which Friis is used, is calculated as follows:

$dCross = \frac{(4 * pi * Ht * Hr)}{lambda}$

Definition at line 263 of file propagation-loss-model.h.

Constructor & Destructor Documentation

ns3::TwoRayGroundPropagationLossModel::TwoRayGroundPropagationLossModel ( )

Definition at line 312 of file propagation-loss-model.cc.

ns3::TwoRayGroundPropagationLossModel::TwoRayGroundPropagationLossModel ( const TwoRayGroundPropagationLossModel & o )

private

Member Function Documentation

double ns3::TwoRayGroundPropagationLossModel::DbmFromW ( double w ) const

private

Definition at line 364 of file propagation-loss-model.cc.

double ns3::TwoRayGroundPropagationLossModel::DbmToW ( double dbm ) const

private

Definition at line 357 of file propagation-loss-model.cc.

int64_t ns3::TwoRayGroundPropagationLossModel::DoAssignStreams ( int64_t stream )

privatevirtual

Definition at line 445 of file propagation-loss-model.cc.

double ns3::TwoRayGroundPropagationLossModel::DoCalcRxPower	(	double	txPowerDbm,
		Ptr< MobilityModel >	a,
		Ptr< MobilityModel >	b
	)		const

privatevirtual

Definition at line 371 of file propagation-loss-model.cc.

References ns3::MobilityModel::GetDistanceFrom(), GetLambda(), ns3::MobilityModel::GetPosition(), m_heightAboveZ, m_lambda, m_minDistance, m_systemLoss, NS_LOG_DEBUG, PI, and ns3::Vector3D::z.

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double ns3::TwoRayGroundPropagationLossModel::GetLambda ( void ) const

Returns: the current wavelength (m)

Definition at line 351 of file propagation-loss-model.cc.

References m_lambda.

Referenced by DoCalcRxPower().

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double ns3::TwoRayGroundPropagationLossModel::GetMinDistance ( void ) const

Returns: the minimum distance.

Definition at line 331 of file propagation-loss-model.cc.

References m_minDistance.

Referenced by GetTypeId().

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double ns3::TwoRayGroundPropagationLossModel::GetSystemLoss ( void ) const

Returns: the current system loss (dimension-less)

Definition at line 321 of file propagation-loss-model.cc.

References m_systemLoss.

TypeId ns3::TwoRayGroundPropagationLossModel::GetTypeId ( void )

static

This method returns the TypeId associated to ns3::TwoRayGroundPropagationLossModel.

This object is accessible through the following paths with Config::Set and Config::Connect:

/NodeList/[i]/DeviceList/[i]/$ns3::WifiNetDevice/Channel/$ns3::YansWifiChannel/PropagationLossModel/$ns3::TwoRayGroundPropagationLossModel

Attributes defined for this type:

Lambda: The wavelength (default is 5.15 GHz at 300 000 km/s).
- Set with class: ns3::DoubleValue
- Underlying type: double -1.79769e+308:1.79769e+308
- Initial value: 0.0582524
- Flags: construct write read
SystemLoss: The system loss
- Set with class: ns3::DoubleValue
- Underlying type: double -1.79769e+308:1.79769e+308
- Initial value: 1
- Flags: construct write read
MinDistance: The distance under which the propagation model refuses to give results (m)
- Set with class: ns3::DoubleValue
- Underlying type: double -1.79769e+308:1.79769e+308
- Initial value: 0.5
- Flags: construct write read
HeightAboveZ: The height of the antenna (m) above the node's Z coordinate
- Set with class: ns3::DoubleValue
- Underlying type: double -1.79769e+308:1.79769e+308
- Initial value: 0
- Flags: construct write read