/* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
/*
* Copyright (c) 2005,2006 INRIA
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation;
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*
* Author: Mathieu Lacage <mathieu.lacage@sophia.inria.fr>
*/
#ifndef INTERFERENCE_HELPER_H
#define INTERFERENCE_HELPER_H
#include <stdint.h>
#include <vector>
#include <list>
#include "wifi-mode.h"
#include "wifi-preamble.h"
#include "wifi-phy-standard.h"
#include "ns3/nstime.h"
#include "ns3/simple-ref-count.h"
#include "ns3/wifi-tx-vector.h"
namespace ns3 {
class ErrorRateModel;
/**
* \ingroup wifi
* \brief handles interference calculations
*/
class InterferenceHelper
{
public:
/**
* Signal event for a packet.
*/
class Event : public SimpleRefCount<InterferenceHelper::Event>
{
public:
/**
* Create an Event with the given parameters.
*
* \param size packet size
* \param payloadMode Wi-Fi mode used for the payload
* \param preamble preamble type
* \param duration duration of the signal
* \param rxPower the receive power (w)
* \param txvector TXVECTOR of the packet
*/
Event (uint32_t size, WifiMode payloadMode,
enum WifiPreamble preamble,
Time duration, double rxPower, WifiTxVector txvector);
~Event ();
/**
* Return the duration of the signal.
*
* \return the duration of the signal
*/
Time GetDuration (void) const;
/**
* Return the start time of the signal.
*
* \return the start time of the signal
*/
Time GetStartTime (void) const;
/**
* Return the end time of the signal.
*
* \return the end time of the signal
*/
Time GetEndTime (void) const;
/**
* Return the receive power (w).
*
* \return the receive power (w)
*/
double GetRxPowerW (void) const;
/**
* Return the size of the packet (bytes).
*
* \return the size of the packet (bytes)
*/
uint32_t GetSize (void) const;
/**
* Return the Wi-Fi mode used for the payload.
*
* \return the Wi-Fi mode used for the payload
*/
WifiMode GetPayloadMode (void) const;
/**
* Return the preamble type of the packet.
*
* \return the preamble type of the packet
*/
enum WifiPreamble GetPreambleType (void) const;
/**
* Return the TXVECTOR of the packet.
*
* \return the TXVECTOR of the packet
*/
WifiTxVector GetTxVector (void) const;
private:
uint32_t m_size;
WifiMode m_payloadMode;
enum WifiPreamble m_preamble;
Time m_startTime;
Time m_endTime;
double m_rxPowerW;
WifiTxVector m_txVector;
};
/**
* A struct for both SNR and PER
*/
struct SnrPer
{
double snr;
double per;
};
InterferenceHelper ();
~InterferenceHelper ();
/**
* Set the noise figure.
*
* \param value noise figure
*/
void SetNoiseFigure (double value);
/**
* Set the error rate model for this interference helper.
*
* \param rate Error rate model
*/
void SetErrorRateModel (Ptr<ErrorRateModel> rate);
/**
* Return the noise figure.
*
* \return the noise figure
*/
double GetNoiseFigure (void) const;
/**
* Return the error rate model.
*
* \return Error rate model
*/
Ptr<ErrorRateModel> GetErrorRateModel (void) const;
/**
* \param energyW the minimum energy (W) requested
* \returns the expected amount of time the observed
* energy on the medium will be higher than
* the requested threshold.
*/
Time GetEnergyDuration (double energyW);
/**
* Add the packet-related signal to interference helper.
*
* \param size packet size
* \param payloadMode Wi-Fi mode for the payload
* \param preamble Wi-Fi preamble for the packet
* \param duration the duration of the signal
* \param rxPower receive power (w)
* \param txvector TXVECTOR of the packet
* \return InterferenceHelper::Event
*/
Ptr<InterferenceHelper::Event> Add (uint32_t size, WifiMode payloadMode,
enum WifiPreamble preamble,
Time duration, double rxPower, WifiTxVector txvector);
/**
* Calculate the SNIR at the start of the packet and accumulate
* all SNIR changes in the snir vector.
*
* \param event the event corresponding to the first time the packet arrives
* \return struct of SNR and PER
*/
struct InterferenceHelper::SnrPer CalculateSnrPer (Ptr<InterferenceHelper::Event> event);
/**
* Notify that RX has started.
*/
void NotifyRxStart ();
/**
* Notify that RX has ended.
*/
void NotifyRxEnd ();
/**
* Erase all events.
*/
void EraseEvents (void);
private:
/**
* Noise and Interference (thus Ni) event.
*/
class NiChange
{
public:
/**
* Create a NiChange at the given time and the amount of NI change.
*
* \param time time of the event
* \param delta the power
*/
NiChange (Time time, double delta);
/**
* Return the event time.
*
* \return the event time.
*/
Time GetTime (void) const;
/**
* Return the power
*
* \return the power
*/
double GetDelta (void) const;
/**
* Compare the event time of two NiChange objects (a < o).
*
* \param o
* \return true if a < o.time, false otherwise
*/
bool operator < (const NiChange& o) const;
private:
Time m_time;
double m_delta;
};
/**
* typedef for a vector of NiChanges
*/
typedef std::vector <NiChange> NiChanges;
/**
* typedef for a list of Events
*/
typedef std::list<Ptr<Event> > Events;
//InterferenceHelper (const InterferenceHelper &o);
//InterferenceHelper &operator = (const InterferenceHelper &o);
/**
* Append the given Event.
*
* \param event
*/
void AppendEvent (Ptr<Event> event);
/**
* Calculate noise and interference power in W.
*
* \param event
* \param ni
* \return noise and interference power
*/
double CalculateNoiseInterferenceW (Ptr<Event> event, NiChanges *ni) const;
/**
* Calculate SNR (linear ratio) from the given signal power and noise+interference power.
* (Mode is not currently used)
*
* \param signal
* \param noiseInterference
* \param mode
* \return SNR in liear ratio
*/
double CalculateSnr (double signal, double noiseInterference, WifiMode mode) const;
/**
* Calculate the success rate of the chunk given the SINR, duration, and Wi-Fi mode.
* The duration and mode are used to calculate how many bits are present in the chunk.
*
* \param snir SINR
* \param duration
* \param mode
* \return the success rate
*/
double CalculateChunkSuccessRate (double snir, Time duration, WifiMode mode) const;
/**
* Calculate the error rate of the given packet. The packet can be divided into
* multiple chunks (e.g. due to interference from other transmissions).
*
* \param event
* \param ni
* \return the error rate of the packet
*/
double CalculatePer (Ptr<const Event> event, NiChanges *ni) const;
double m_noiseFigure; /**< noise figure (linear) */
Ptr<ErrorRateModel> m_errorRateModel;
/// Experimental: needed for energy duration calculation
NiChanges m_niChanges;
double m_firstPower;
bool m_rxing;
/// Returns an iterator to the first nichange, which is later than moment
NiChanges::iterator GetPosition (Time moment);
/**
* Add NiChange to the list at the appropriate position.
*
* \param change
*/
void AddNiChangeEvent (NiChange change);
};
} // namespace ns3
#endif /* INTERFERENCE_HELPER_H */