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ns3::TwoRayGroundPropagationLossModel Class Reference

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 GetFrequency (void) const
 
double GetMinDistance (void) const
 
double GetSystemLoss (void) const
 
void SetFrequency (double frequency)
 
void SetHeightAboveZ (double heightAboveZ)
 
void SetMinDistance (double minDistance)
 
void SetSystemLoss (double systemLoss)
 
- Public Member Functions inherited from ns3::PropagationLossModel
 PropagationLossModel ()
 
virtual ~PropagationLossModel ()
 
int64_t AssignStreams (int64_t stream)
 If this loss model uses objects of type RandomVariableStream, set the stream numbers to the integers starting with the offset 'stream'. More...
 
double CalcRxPower (double txPowerDbm, Ptr< MobilityModel > a, Ptr< MobilityModel > b) const
 
Ptr< PropagationLossModelGetNext ()
 Gets the next PropagationLossModel in the chain of loss models that act on the signal. More...
 
void SetNext (Ptr< PropagationLossModel > next)
 Enables a chain of loss models to act on the signal. More...
 
- Public Member Functions inherited from ns3::Object
 Object ()
 
virtual ~Object ()
 
void AggregateObject (Ptr< Object > other)
 
void Dispose (void)
 Run the DoDispose methods of this object and all the objects aggregated to it. More...
 
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 Initialize (void)
 This method calls the virtual DoInitialize method on all the objects aggregated to this object. More...
 
- Public Member Functions inherited from ns3::SimpleRefCount< Object, ObjectBase, ObjectDeleter >
 SimpleRefCount ()
 Constructor. More...
 
 SimpleRefCount (const SimpleRefCount &o)
 Copy constructor. More...
 
uint32_t GetReferenceCount (void) const
 Get the reference count of the object. More...
 
SimpleRefCountoperator= (const SimpleRefCount &o)
 Assignment. More...
 
void Ref (void) const
 Increment the reference count. More...
 
void Unref (void) const
 Decrement the reference count. More...
 
- Public Member Functions inherited from ns3::ObjectBase
virtual ~ObjectBase ()
 Virtual destructor. More...
 
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)
 
- Static Public Member Functions inherited from ns3::PropagationLossModel
static TypeId GetTypeId (void)
 
- Static Public Member Functions inherited from ns3::Object
static TypeId GetTypeId (void)
 Register this type. More...
 
- Static Public Member Functions inherited from ns3::SimpleRefCount< Object, ObjectBase, ObjectDeleter >
static void Cleanup (void)
 Noop. More...
 
- Static Public Member Functions inherited from ns3::ObjectBase
static TypeId GetTypeId (void)
 Get the type ID. More...
 

Private Member Functions

 TwoRayGroundPropagationLossModel (const TwoRayGroundPropagationLossModel &o)
 
double DbmFromW (double w) const
 
double DbmToW (double dbm) const
 
virtual int64_t DoAssignStreams (int64_t stream)
 Subclasses must implement this; those not using random variables can return zero. More...
 
virtual double DoCalcRxPower (double txPowerDbm, Ptr< MobilityModel > a, Ptr< MobilityModel > b) const
 
TwoRayGroundPropagationLossModeloperator= (const TwoRayGroundPropagationLossModel &o)
 

Private Attributes

double m_frequency
 
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)
 This method is called by Object::Dispose or by the object's destructor, whichever comes first. More...
 
virtual void DoInitialize (void)
 This method is called only once by Object::Initialize. More...
 
virtual void NotifyNewAggregate (void)
 This method is invoked whenever two sets of objects are aggregated together. More...
 
- Protected Member Functions inherited from ns3::ObjectBase
void ConstructSelf (const AttributeConstructionList &attributes)
 
virtual void NotifyConstructionCompleted (void)
 This method is invoked once all member attributes have been initialized. More...
 

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} $

In the implementation, $ \lambda $ is calculated as $ \frac{C}{f} $, where $ C = 299792458$ m/s is the speed of light in vacuum, and $ f $ is the frequency in Hz which can be configured by the user via the Frequency attribute.

Config Paths

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

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

Attributes

  • Frequency: The carrier frequency (in Hz) at which propagation occurs (default is 5.15 GHz).
    • Set with class: ns3::DoubleValue
    • Underlying type: double -1.79769e+308:1.79769e+308
    • Initial value: 5.15e+09
    • 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

No TraceSources are defined for this type.

Definition at line 303 of file propagation-loss-model.h.

Constructor & Destructor Documentation

ns3::TwoRayGroundPropagationLossModel::TwoRayGroundPropagationLossModel ( )

Definition at line 317 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 368 of file propagation-loss-model.cc.

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

Definition at line 361 of file propagation-loss-model.cc.

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

Subclasses must implement this; those not using random variables can return zero.

Implements ns3::PropagationLossModel.

Definition at line 449 of file propagation-loss-model.cc.

double ns3::TwoRayGroundPropagationLossModel::DoCalcRxPower ( double  txPowerDbm,
Ptr< MobilityModel a,
Ptr< MobilityModel b 
) const
privatevirtual
double ns3::TwoRayGroundPropagationLossModel::GetFrequency ( void  ) const
Returns
the current frequency (Hz)

Definition at line 355 of file propagation-loss-model.cc.

References m_frequency.

Referenced by GetTypeId().

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double ns3::TwoRayGroundPropagationLossModel::GetMinDistance ( void  ) const
Returns
the minimum distance.

Definition at line 336 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 326 of file propagation-loss-model.cc.

References m_systemLoss.

TypeId ns3::TwoRayGroundPropagationLossModel::GetTypeId ( void  )
static

Definition at line 287 of file propagation-loss-model.cc.

References GetFrequency(), GetMinDistance(), m_heightAboveZ, m_systemLoss, SetFrequency(), SetMinDistance(), and ns3::TypeId::SetParent().

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TwoRayGroundPropagationLossModel& ns3::TwoRayGroundPropagationLossModel::operator= ( const TwoRayGroundPropagationLossModel o)
private
void ns3::TwoRayGroundPropagationLossModel::SetFrequency ( double  frequency)
Parameters
frequency(Hz)

Set the carrier frequency used in the TwoRayGround model calculation.

Definition at line 347 of file propagation-loss-model.cc.

References m_frequency, and m_lambda.

Referenced by GetTypeId().

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void ns3::TwoRayGroundPropagationLossModel::SetHeightAboveZ ( double  heightAboveZ)
Parameters
heightAboveZthe model antenna height above the node's Z coordinate

Set the model antenna height above the node's Z coordinate

Definition at line 341 of file propagation-loss-model.cc.

References m_heightAboveZ.

void ns3::TwoRayGroundPropagationLossModel::SetMinDistance ( double  minDistance)
Parameters
minDistancethe minimum distance

Below this distance, the txpower is returned unmodified as the rxpower.

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

References m_minDistance.

Referenced by GetTypeId().

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void ns3::TwoRayGroundPropagationLossModel::SetSystemLoss ( double  systemLoss)
Parameters
systemLoss(dimension-less)

Set the system loss used by the TwoRayGround propagation model.

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

References m_systemLoss.

Member Data Documentation

double ns3::TwoRayGroundPropagationLossModel::m_frequency
private

Definition at line 363 of file propagation-loss-model.h.

Referenced by GetFrequency(), and SetFrequency().

double ns3::TwoRayGroundPropagationLossModel::m_heightAboveZ
private

Definition at line 366 of file propagation-loss-model.h.

Referenced by DoCalcRxPower(), GetTypeId(), and SetHeightAboveZ().

double ns3::TwoRayGroundPropagationLossModel::m_lambda
private

Definition at line 362 of file propagation-loss-model.h.

Referenced by DoCalcRxPower(), and SetFrequency().

double ns3::TwoRayGroundPropagationLossModel::m_minDistance
private

Definition at line 365 of file propagation-loss-model.h.

Referenced by DoCalcRxPower(), GetMinDistance(), and SetMinDistance().

double ns3::TwoRayGroundPropagationLossModel::m_systemLoss
private

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

Referenced by DoCalcRxPower(), GetSystemLoss(), GetTypeId(), and SetSystemLoss().

const double ns3::TwoRayGroundPropagationLossModel::PI = 3.14159265358979323846
staticprivate

Definition at line 361 of file propagation-loss-model.h.

Referenced by DoCalcRxPower().


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