itu-r-1411-nlos-over-rooftop-propagation-loss-model.cc

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/*
 * Copyright (c) 2011, 2012 Centre Tecnologic de Telecomunicacions de Catalunya (CTTC)
 *
 * 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: Marco Miozzo  <marco.miozzo@cttc.es>,
 *         Nicola Baldo <nbaldo@cttc.es>
 *
 */
#include "itu-r-1411-nlos-over-rooftop-propagation-loss-model.h"
 
#include "ns3/double.h"
#include "ns3/enum.h"
#include "ns3/log.h"
#include "ns3/mobility-model.h"
 
#include <cmath>
 
namespace ns3
{
 
NS_LOG_COMPONENT_DEFINE("ItuR1411NlosOverRooftopPropagationLossModel");
 
NS_OBJECT_ENSURE_REGISTERED(ItuR1411NlosOverRooftopPropagationLossModel);
 
TypeId
ItuR1411NlosOverRooftopPropagationLossModel::GetTypeId()
{
    static TypeId tid =
        TypeId("ns3::ItuR1411NlosOverRooftopPropagationLossModel")
            .SetParent<PropagationLossModel>()
            .SetGroupName("Propagation")
            .AddConstructor<ItuR1411NlosOverRooftopPropagationLossModel>()
            .AddAttribute(
                "Frequency",
                "The Frequency  (default is 2.106 GHz).",
                DoubleValue(2160e6),
                MakeDoubleAccessor(&ItuR1411NlosOverRooftopPropagationLossModel::SetFrequency),
                MakeDoubleChecker<double>())
            .AddAttribute(
                "Environment",
                "Environment Scenario",
                EnumValue(UrbanEnvironment),
                MakeEnumAccessor(&ItuR1411NlosOverRooftopPropagationLossModel::m_environment),
                MakeEnumChecker(UrbanEnvironment,
                                "Urban",
                                SubUrbanEnvironment,
                                "SubUrban",
                                OpenAreasEnvironment,
                                "OpenAreas"))
            .AddAttribute(
                "CitySize",
                "Dimension of the city",
                EnumValue(LargeCity),
                MakeEnumAccessor(&ItuR1411NlosOverRooftopPropagationLossModel::m_citySize),
                MakeEnumChecker(SmallCity, "Small", MediumCity, "Medium", LargeCity, "Large"))
            .AddAttribute(
                "RooftopLevel",
                "The height of the rooftop level in meters",
                DoubleValue(20.0),
                MakeDoubleAccessor(&ItuR1411NlosOverRooftopPropagationLossModel::m_rooftopHeight),
                MakeDoubleChecker<double>(0.0, 90.0))
            .AddAttribute("StreetsOrientation",
                          "The orientation of streets in degrees [0,90] with respect to the "
                          "direction of propagation",
                          DoubleValue(45.0),
                          MakeDoubleAccessor(
                              &ItuR1411NlosOverRooftopPropagationLossModel::m_streetsOrientation),
                          MakeDoubleChecker<double>(0.0, 90.0))
            .AddAttribute(
                "StreetsWidth",
                "The width of streets",
                DoubleValue(20.0),
                MakeDoubleAccessor(&ItuR1411NlosOverRooftopPropagationLossModel::m_streetsWidth),
                MakeDoubleChecker<double>(0.0, 1000.0))
            .AddAttribute(
                "BuildingsExtend",
                "The distance over which the buildings extend",
                DoubleValue(80.0),
                MakeDoubleAccessor(&ItuR1411NlosOverRooftopPropagationLossModel::m_buildingsExtend),
                MakeDoubleChecker<double>())
            .AddAttribute("BuildingSeparation",
                          "The separation between buildings",
                          DoubleValue(50.0),
                          MakeDoubleAccessor(
                              &ItuR1411NlosOverRooftopPropagationLossModel::m_buildingSeparation),
                          MakeDoubleChecker<double>());
 
    return tid;
}
 
ItuR1411NlosOverRooftopPropagationLossModel::ItuR1411NlosOverRooftopPropagationLossModel()
    : PropagationLossModel()
{
}
 
ItuR1411NlosOverRooftopPropagationLossModel::~ItuR1411NlosOverRooftopPropagationLossModel()
{
}
 
double
ItuR1411NlosOverRooftopPropagationLossModel::GetLoss(Ptr<MobilityModel> a,
                                                     Ptr<MobilityModel> b) const
{
    NS_LOG_FUNCTION(this << a << b);
    double Lori = 0.0;
    double fmhz = m_frequency / 1e6;
 
    NS_ASSERT_MSG(((m_streetsOrientation >= 0) && (m_streetsOrientation <= 90)),
                  " Street Orientation must be in [0,90]");
    if (m_streetsOrientation < 35)
    {
        Lori = -10.0 + 0.354 * m_streetsOrientation;
    }
    else if ((m_streetsOrientation >= 35) && (m_streetsOrientation < 55))
    {
        Lori = 2.5 + 0.075 * (m_streetsOrientation - 35);
    }
    else // m_streetsOrientation >= 55
    {
        Lori = 2.5 + 0.075 * (m_streetsOrientation - 55);
    }
 
    double distance = a->GetDistanceFrom(b);
    double hb = (a->GetPosition().z > b->GetPosition().z ? a->GetPosition().z : b->GetPosition().z);
    double hm = (a->GetPosition().z < b->GetPosition().z ? a->GetPosition().z : b->GetPosition().z);
    NS_ASSERT_MSG(hm > 0 && hb > 0, "nodes' height must be greater then 0");
    double Dhb = hb - m_rooftopHeight;
    double ds = (m_lambda * distance * distance) / (Dhb * Dhb);
    double Lmsd = 0.0;
    NS_LOG_LOGIC(this << " build " << m_buildingsExtend << " ds " << ds << " roof "
                      << m_rooftopHeight << " hb " << hb << " lambda " << m_lambda);
    if (ds < m_buildingsExtend)
    {
        double Lbsh = 0.0;
        double ka = 0.0;
        double kd = 0.0;
        double kf = 0.0;
        if (hb > m_rooftopHeight)
        {
            Lbsh = -18 * std::log10(1 + Dhb);
            ka = (fmhz > 2000 ? 71.4 : 54.0);
            kd = 18.0;
        }
        else
        {
            Lbsh = 0;
            kd = 18.0 - 15 * Dhb / a->GetPosition().z;
            if (distance < 500)
            {
                ka = 54.0 - 1.6 * Dhb * distance / 1000;
            }
            else
            {
                ka = 54.0 - 0.8 * Dhb;
            }
        }
        if (fmhz > 2000)
        {
            kf = -8;
        }
        else if ((m_environment == UrbanEnvironment) && (m_citySize == LargeCity))
        {
            kf = -4 + 0.7 * (fmhz / 925.0 - 1);
        }
        else
        {
            kf = -4 + 1.5 * (fmhz / 925.0 - 1);
        }
 
        Lmsd = Lbsh + ka + kd * std::log10(distance / 1000.0) + kf * std::log10(fmhz) -
               9.0 * std::log10(m_buildingSeparation);
    }
    else
    {
        double theta = std::atan(Dhb / m_buildingSeparation);
        double rho = std::sqrt(Dhb * Dhb + m_buildingSeparation * m_buildingSeparation);
        double Qm = 0.0;
        if ((hb > m_rooftopHeight - 1.0) && (hb < m_rooftopHeight + 1.0))
        {
            Qm = m_buildingSeparation / distance;
        }
        else if (hb > m_rooftopHeight)
        {
            Qm = 2.35 * pow(Dhb / distance * std::sqrt(m_buildingSeparation / m_lambda), 0.9);
        }
        else
        {
            Qm = m_buildingSeparation / (2 * M_PI * distance) * std::sqrt(m_lambda / rho) *
                 (1 / theta - (1 / (2 * M_PI + theta)));
        }
        Lmsd = -10 * std::log10(Qm * Qm);
    }
    double Lbf = 32.4 + 20 * std::log10(distance / 1000) + 20 * std::log10(fmhz);
    double Dhm = m_rooftopHeight - hm;
    double Lrts = -8.2 - 10 * std::log10(m_streetsWidth) + 10 * std::log10(fmhz) +
                  20 * std::log10(Dhm) + Lori;
    NS_LOG_LOGIC(this << " Lbf " << Lbf << " Lrts " << Lrts << " Dhm" << Dhm << " Lmsd " << Lmsd);
    double loss = 0.0;
    if (Lrts + Lmsd > 0)
    {
        loss = Lbf + Lrts + Lmsd;
    }
    else
    {
        loss = Lbf;
    }
    return loss;
}
 
void
ItuR1411NlosOverRooftopPropagationLossModel::SetFrequency(double freq)
{
    m_frequency = freq;
    m_lambda = 299792458.0 / freq;
}
 
double
ItuR1411NlosOverRooftopPropagationLossModel::DoCalcRxPower(double txPowerDbm,
                                                           Ptr<MobilityModel> a,
                                                           Ptr<MobilityModel> b) const
{
    return (txPowerDbm - GetLoss(a, b));
}
 
int64_t
ItuR1411NlosOverRooftopPropagationLossModel::DoAssignStreams(int64_t stream)
{
    return 0;
}
 
} // namespace ns3