Composite and Jakes propagation loss models.
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/src/devices/wifi/composite-propagation-loss-model.cc Fri Mar 21 04:51:36 2008 +0100
@@ -0,0 +1,79 @@
+/* -*- Mode: C++; c-file-style: "gnu"; indent-tabs-mode:nil; -*- */
+/*
+ * Copyright (c) 2005,2006,2007 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: Federico Maguolo <maguolof@dei.unipd.it>
+ */
+
+#include "ns3/simulator.h"
+#include "ns3/uinteger.h"
+#include "ns3/double.h"
+#include "ns3/random-variable.h"
+#include "ns3/default-value.h"
+#include "ns3/mobility-model.h"
+#include "composite-propagation-loss-model.h"
+#include <math.h>
+
+namespace ns3 {
+
+
+
+NS_OBJECT_ENSURE_REGISTERED (CompositePropagationLossModel);
+
+TypeId
+CompositePropagationLossModel::GetTypeId (void)
+{
+ static TypeId tid = TypeId ("ns3::CompositePropagationLossModel")
+ .SetParent<PropagationLossModel> ()
+ .AddConstructor<CompositePropagationLossModel> ()
+ ;
+ return tid;
+}
+
+CompositePropagationLossModel::CompositePropagationLossModel ()
+{
+ AddDefaults ();
+}
+
+CompositePropagationLossModel::~CompositePropagationLossModel ()
+{}
+
+void
+CompositePropagationLossModel::AddDefaults ()
+{}
+
+void
+CompositePropagationLossModel::AddPropagationLossModel (Ptr<PropagationLossModel> pl)
+{
+ m_propagationModels.push_back (pl);
+}
+
+double
+CompositePropagationLossModel::GetLoss (Ptr<MobilityModel> a,
+ Ptr<MobilityModel> b) const
+{
+ double rxc = 0.0;
+ for(PropagationModelList::const_iterator i = m_propagationModels.begin ();
+ i != m_propagationModels.end ();
+ i++) {
+ rxc += (*i)->GetLoss (a, b);
+ }
+
+ return rxc;
+}
+
+} // namespace ns3
+
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/src/devices/wifi/composite-propagation-loss-model.h Fri Mar 21 04:51:36 2008 +0100
@@ -0,0 +1,63 @@
+/* -*- Mode: C++; c-file-style: "gnu"; indent-tabs-mode:nil; -*- */
+/*
+ * Copyright (c) 2005,2006,2007 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: Federico Maguolo <maguolof@dei.unipd.it>
+ */
+#ifndef PROPAGATION_COMP_MODEL_H
+#define PROPAGATION_COMP_MODEL_H
+
+#include "ns3/nstime.h"
+#include "propagation-loss-model.h"
+
+namespace ns3 {
+
+/**
+ * \brief a Composite propagation loss model
+ *
+ * This model is use to compute the receivng power
+ * using more than one propagation loss model (e.g. distance loss
+ * and jakes).
+ *
+ * The received power is computed considering the cascade of the models
+ */
+class CompositePropagationLossModel : public PropagationLossModel {
+public:
+ static TypeId GetTypeId (void);
+ CompositePropagationLossModel ();
+ virtual ~CompositePropagationLossModel ();
+
+ virtual double GetLoss (Ptr<MobilityModel> a,
+ Ptr<MobilityModel> b) const;
+ /**
+ * \param pl the propagation loss model to add
+ *
+ * Insert a propagation loss model to the composite.
+ */
+ void AddPropagationLossModel (Ptr<PropagationLossModel> pl);
+protected:
+ virtual void AddDefaults (void);
+private:
+ typedef std::vector<Ptr<PropagationLossModel> > PropagationModelList;
+ PropagationModelList m_propagationModels;
+};
+
+
+} // namespace ns3
+
+#endif /* PROPAGATION_COMP_MODEL_H */
+
+
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/src/devices/wifi/jakes-propagation-loss-model.cc Fri Mar 21 04:51:36 2008 +0100
@@ -0,0 +1,235 @@
+/* -*- Mode: C++; c-file-style: "gnu"; indent-tabs-mode:nil; -*- */
+/*
+ * Copyright (c) 2005,2006,2007 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: Federico Maguolo <maguolof@dei.unipd.it>
+ */
+
+#include "ns3/simulator.h"
+#include "ns3/uinteger.h"
+#include "ns3/double.h"
+#include "ns3/random-variable.h"
+#include "ns3/default-value.h"
+#include "ns3/mobility-model.h"
+#include "ns3/log.h"
+#include "jakes-propagation-loss-model.h"
+#include <math.h>
+
+NS_LOG_COMPONENT_DEFINE ("Jakes");
+
+namespace ns3 {
+
+
+
+class JakesPropagationLossModel::PathCoefficients {
+public:
+ PathCoefficients (Ptr<const JakesPropagationLossModel> jakes,
+ Ptr<MobilityModel> receiver,
+ uint8_t nRays,
+ uint8_t nOscillators);
+ ~PathCoefficients ();
+ double GetLoss (void);
+ Ptr<MobilityModel> GetReceiver (void);
+private:
+ void DoConstruct (void);
+ Ptr<MobilityModel> m_receiver;
+ uint8_t m_nOscillators;
+ uint8_t m_nRays;
+ double **m_phases;
+ Time m_lastUpdate;
+ Ptr<const JakesPropagationLossModel> m_jakes;
+};
+
+
+JakesPropagationLossModel::PathCoefficients::PathCoefficients (Ptr<const JakesPropagationLossModel> jakes,
+ Ptr<MobilityModel> receiver,
+ uint8_t nRays,
+ uint8_t nOscillators)
+ : m_receiver (receiver),
+ m_nOscillators (nOscillators),
+ m_nRays (nRays),
+ m_jakes(jakes)
+{
+ DoConstruct ();
+}
+
+JakesPropagationLossModel::PathCoefficients::~PathCoefficients ()
+{
+ for (uint8_t i = 0; i < m_nRays; i++) {
+ delete [] m_phases[i];
+ }
+ delete [] m_phases;
+}
+
+void
+JakesPropagationLossModel::PathCoefficients::DoConstruct ()
+{
+ m_phases = new double*[m_nRays];
+ for (uint8_t i = 0; i < m_nRays; i++) {
+ m_phases[i] = new double[m_nOscillators + 1];
+ for (uint8_t j = 0; j <= m_nOscillators; j++) {
+ m_phases[i][j] = 2.0 * JakesPropagationLossModel::PI * m_jakes->m_variable.GetValue ();
+ }
+ }
+ m_lastUpdate = Simulator::Now ();
+}
+
+Ptr<MobilityModel>
+JakesPropagationLossModel::PathCoefficients::GetReceiver ()
+{
+ return m_receiver;
+}
+
+double
+JakesPropagationLossModel::PathCoefficients::GetLoss (void)
+{
+ uint16_t N = 4 * m_nOscillators + 2;
+ Time interval = Simulator::Now () - m_lastUpdate;
+ ComplexNumber coef= {0.0, 0.0};
+ ComplexNumber fading;
+ double norm = 0.0;
+ for (uint8_t i = 0; i < m_nRays; i++) {
+ fading.real = 0.0;
+ fading.imag = 0.0;
+ for (uint8_t j = 0; j <= m_nOscillators; j++) {
+ m_phases[i][j] += 2.0 * JakesPropagationLossModel::PI * cos (2.0 * JakesPropagationLossModel::PI * j / N) * m_jakes->m_fd * interval.GetSeconds ();
+ m_phases[i][j] -= 2.0 * JakesPropagationLossModel::PI * floor (m_phases[i][j] / 2.0 / JakesPropagationLossModel::PI);
+ fading.real += m_jakes->m_amp[j].real * cos (m_phases[i][j]);
+ fading.imag += m_jakes->m_amp[j].imag * cos (m_phases[i][j]);
+ norm += sqrt(pow (m_jakes->m_amp[j].real, 2) + pow(m_jakes->m_amp[j].imag, 2));
+ }
+ coef.real += fading.real;
+ coef.imag += fading.imag;
+ }
+ m_lastUpdate = Simulator::Now ();
+ double k = sqrt (pow (coef.real, 2) + pow (coef.imag, 2)) / norm;
+ NS_LOG_DEBUG ("Jakes coef "<< k << " (" << 10 * log10 (k) << "dB)");
+ return 10 * log10 (k);
+}
+
+NS_OBJECT_ENSURE_REGISTERED (JakesPropagationLossModel);
+
+const double JakesPropagationLossModel::PI = 3.1415;
+
+TypeId
+JakesPropagationLossModel::GetTypeId (void)
+{
+ static TypeId tid = TypeId ("ns3::JakesPropagationLossModel")
+ .SetParent<PropagationLossModel> ()
+ .AddConstructor<JakesPropagationLossModel> ()
+ .AddAttribute ("NumberOfRaysPerPath",
+ "The number of rays to use by default for compute the fading coeficent for a given path (default is 1)",
+ Uinteger (1),
+ MakeUintegerAccessor (&JakesPropagationLossModel::m_nRays),
+ MakeUintegerChecker<uint8_t> ())
+ .AddAttribute ("NumberOfOscillatorsPerRay",
+ "The number of oscillators to use by default for compute the coeficent for a given ray of a given path (default is 4)",
+ Uinteger (4),
+ MakeUintegerAccessor (&JakesPropagationLossModel::m_nOscillators),
+ MakeUintegerChecker<uint8_t> ())
+ .AddAttribute ("DopplerFreq",
+ "The doppler frequency in Hz (f_d = v / lambda = v * f / c, the defualt is 0)",
+ Double(0.0),
+ MakeDoubleAccessor (&JakesPropagationLossModel::m_fd),
+ MakeDoubleChecker<double> ())
+ .AddAttribute ("Distribution",
+ "The distribution to choose the initial phases.",
+ ConstantVariable (1.0),
+ MakeRandomVariableAccessor (&JakesPropagationLossModel::m_variable),
+ MakeRandomVariableChecker ())
+ ;
+ return tid;
+}
+
+JakesPropagationLossModel::JakesPropagationLossModel ()
+{
+ DoConstruct ();
+}
+
+JakesPropagationLossModel::~JakesPropagationLossModel ()
+{
+ delete [] m_amp;
+ for (PathsList::iterator i = m_paths.end (); i != m_paths.begin (); i--) {
+ PathsSet *ps = *i;
+ for (DestinationList::iterator r = ps->receivers.begin (); r != ps->receivers.end (); r++) {
+ PathCoefficients *pc = *r;
+ delete pc;
+ }
+ delete ps;
+ }
+}
+
+void
+JakesPropagationLossModel::DoConstruct ()
+{
+ uint16_t N = 4 * m_nOscillators + 2;
+ m_amp = new ComplexNumber[m_nOscillators + 1];
+ m_amp[0].real = 2.0 * sqrt(2.0 / N) * cos (PI / 4.0);
+ m_amp[0].imag = 2.0 * sqrt(2.0 / N) * sin (PI / 4.0);
+ for (uint8_t i = 1; i <= m_nOscillators; i++) {
+ double beta = PI * (double)i / m_nOscillators;
+ m_amp[i].real = 4.0 * cos (beta) / sqrt(N);
+ m_amp[i].imag = 4.0 * sin (beta) / sqrt(N);
+ }
+}
+
+void
+JakesPropagationLossModel::SetNRays (uint8_t nRays)
+{
+ m_nRays = nRays;
+}
+
+void
+JakesPropagationLossModel::SetNOscillators (uint8_t nOscillators)
+{
+ m_nOscillators = nOscillators;
+}
+
+double
+JakesPropagationLossModel::GetLoss (Ptr<MobilityModel> a,
+ Ptr<MobilityModel> b) const
+{
+ PathsList::iterator i = m_paths.end ();
+ while (i != m_paths.begin ()) {
+ i--;
+ PathsSet *ps = *i;
+ if (PeekPointer (ps->sender) == PeekPointer(a)) {
+ m_paths.erase (i);
+ m_paths.push_back (ps);
+ for (DestinationList::iterator r = ps->receivers.begin (); r != ps->receivers.end (); r++) {
+ PathCoefficients *pc = *r;
+ if (PeekPointer (pc->GetReceiver ()) == PeekPointer (b)) {
+ ps->receivers.erase (r);
+ ps->receivers.push_back (pc);
+ return pc->GetLoss ();
+ }
+ }
+ PathCoefficients *pc = new PathCoefficients (this, b, m_nRays, m_nOscillators);
+ ps->receivers.push_back (pc);
+ return pc->GetLoss ();
+ }
+ }
+ PathsSet *ps = new PathsSet;
+ ps->sender = a;
+ PathCoefficients *pc = new PathCoefficients (this, b, m_nRays, m_nOscillators);
+ ps->receivers.push_back (pc);
+ m_paths.push_back (ps);
+ return pc->GetLoss ();
+}
+
+
+} // namespace ns3
+
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/src/devices/wifi/jakes-propagation-loss-model.h Fri Mar 21 04:51:36 2008 +0100
@@ -0,0 +1,131 @@
+/* -*- Mode: C++; c-file-style: "gnu"; indent-tabs-mode:nil; -*- */
+/*
+ * Copyright (c) 2005,2006,2007 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: Federico Maguolo <maguolof@dei.unipd.it>
+ */
+#ifndef PROPAGATION_JAKES_MODEL_H
+#define PROPAGATION_JAKES_MODEL_H
+
+#include "ns3/nstime.h"
+#include "propagation-loss-model.h"
+
+namespace ns3 {
+
+
+/**
+ * \brief a Jakes propagation loss model
+ *
+ * The Jakes propagation loss model implemented here is
+ * described in [1].
+ *
+ *
+ * We call path the set of rays that depart from a given
+ * transmitter and arrive to a given receiver. For each ray
+ * The complex coefficient is compute as follow:
+ * \f[ u(t)=u_c(t) + j u_s(t)\f]
+ * \f[ u_c(t) = \frac{2}{\sqrt{N}}\sum_{n=0}^{M}a_n\cos(\omega_n t+\phi_n)\f]
+ * \f[ u_s(t) = \frac{2}{\sqrt{N}}\sum_{n=0}^{M}b_n\cos(\omega_n t+\phi_n)\f]
+ * where
+ * \f[ a_n=\left \{ \begin{array}{ll}
+ * \sqrt{2}\cos\beta_0 & n=0 \\
+ * 2\cos\beta_n & n=1,2,\ldots,M
+ * \end{array}
+ * \right .\f]
+ * \f[ b_n=\left \{ \begin{array}{ll}
+ * \sqrt{2}\sin\beta_0 & n=0 \\
+ * 2\sin\beta_n & n=1,2,\ldots,M
+ * \end{array}
+ * \right .\f]
+ * \f[ \beta_n=\left \{ \begin{array}{ll}
+ * \frac{\pi}{4} & n=0 \\
+ * \frac{\pi n}{M} & n=1,2,\ldots,M
+ * \end{array}
+ * \right .\f]
+ * \f[ \omega_n=\left \{ \begin{array}{ll}
+ * 2\pi f_d & n=0 \\
+ * 2\pi f_d \cos\frac{2\pi n}{N} & n=1,2,\ldots,M
+ * \end{array}
+ * \right .\f]
+ *
+ * The parameter \f$f_d\f$ is the doppler frequency and \f$N=4M+2\f$ where
+ * \f$M\f$ is the number of oscillators per ray.
+ *
+ * The attenuation coefficent of the path is the magnitude of the sum of
+ * all the ray coefficients. This attenuation coefficient could be greater than
+ * \f$1\f$, hence it is divide by \f$ \frac{2N_r}{\sqrt{N}} \sum_{n+0}^{M}\sqrt{a_n^2 +b_n^2}\f$
+ * where \f$N_r\f$ is the number of rays.
+ *
+ * The initail phases \f$\phi_i\f$ are random and they are choosen according
+ * to a given distribution.
+ *
+ * [1] Y. R. Zheng and C. Xiao, "Simulation Models With Correct
+ * Statistical Properties for Rayleigh Fading Channel", IEEE
+ * Trans. on Communications, Vol. 51, pp 920-928, June 2003
+ */
+class JakesPropagationLossModel : public PropagationLossModel
+{
+public:
+ static TypeId GetTypeId (void);
+ JakesPropagationLossModel ();
+ virtual ~JakesPropagationLossModel ();
+
+ virtual double GetLoss (Ptr<MobilityModel> a,
+ Ptr<MobilityModel> b) const;
+ /**
+ * \param nRays Number of rays per path
+ *
+ * Set the number of rays for each path
+ */
+ void SetNRays (uint8_t nRays);
+ /**
+ * \param nOscillators Number of oscillators
+ *
+ * Set the number of oscillators to use to compute the ray coefficient
+ */
+ void SetNOscillators (uint8_t nOscillators);
+protected:
+ class PathCoefficients;
+ struct ComplexNumber {
+ double real;
+ double imag;
+ };
+ friend class PathCoefficents;
+
+ static const double PI;
+ ComplexNumber* m_amp;
+ RandomVariable m_variable;
+ double m_fd;
+private:
+ typedef std::vector<PathCoefficients *> DestinationList;
+ struct PathsSet {
+ Ptr<MobilityModel> sender;
+ DestinationList receivers;
+ };
+ typedef std::vector<PathsSet *> PathsList;
+
+ void DoConstruct (void);
+
+ mutable PathsList m_paths;
+ uint8_t m_nRays;
+ uint8_t m_nOscillators;
+};
+
+} // namespace ns3
+
+#endif /* PROPAGATION_JAKES_MODEL_H */
+
+
--- a/src/devices/wifi/wscript Fri Mar 21 04:49:23 2008 +0100
+++ b/src/devices/wifi/wscript Fri Mar 21 04:51:36 2008 +0100
@@ -5,6 +5,8 @@
obj.source = [
'propagation-delay-model.cc',
'propagation-loss-model.cc',
+ 'composite-propagation-loss-model.cc',
+ 'jakes-propagation-loss-model.cc',
'wifi-channel.cc',
'wifi-mode.cc',
'ssid.cc',
@@ -43,6 +45,8 @@
headers.source = [
'propagation-delay-model.h',
'propagation-loss-model.h',
+ 'composite-propagation-loss-model.h',
+ 'jakes-propagation-loss-model.h',
'wifi-net-device.h',
'wifi-channel.h',
'wifi-mode.h',