/* -*-  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>

 */

#include "error-rate-model.h"

namespace ns3 {

{

  static TypeId tid = TypeId ("ns3::ErrorRateModel")

    .SetParent<Object> ()

    ;

  return tid;

}

double 

ErrorRateModel::CalculateSnr (WifiMode txMode, double ber) const

{

  // This is a very simple binary search.

  double low, high, precision;

  low = 1e-25;

  high = 1e25;

  precision = 1e-12;

  while (high - low > precision) 

    {

      NS_ASSERT (high >= low);

      double middle = low + (high - low) / 2;

      if ((1 - GetChunkSuccessRate (txMode, middle, 1)) > ber) 

        {

          low = middle;

        } 

      else 

        {

          high = middle;

        }

    }

  return low;

}

} // namespace ns3