/* -*-  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 ERROR_RATE_MODEL_H

#define ERROR_RATE_MODEL_H

#include <stdint.h>

#include "wifi-mode.h"

#include "ns3/object.h"

namespace ns3 {

class ErrorRateModel : public Object

{

public:

  static TypeId GetTypeId (void);

  ErrorRateModel ();

  /**

   * \param txMode a specific transmission mode

   * \param ber a target ber

   * \returns the snr which corresponds to the requested

   *          ber.

   */

  double CalculateSnr (WifiMode txMode, double ber) const;

  double GetChunkSuccessRate (WifiMode mode, double snr, uint32_t nbits) const;

private:

  double Log2 (double val) const;

  double GetBpskBer (double snr, uint32_t signalSpread, uint32_t phyRate) const;

  double GetQamBer (double snr, unsigned int m, uint32_t signalSpread, uint32_t phyRate) const;

  uint32_t Factorial (uint32_t k) const;

  double Binomial (uint32_t k, double p, uint32_t n) const;

  double CalculatePdOdd (double ber, unsigned int d) const;

  double CalculatePdEven (double ber, unsigned int d) const;

  double CalculatePd (double ber, unsigned int d) const;

  double GetFecBpskBer (double snr, double nbits, 

                        uint32_t signalSpread, uint32_t phyRate,

                        uint32_t dFree, uint32_t adFree) const;

  double GetFecQamBer (double snr, uint32_t nbits, 

                       uint32_t signalSpread,

                       uint32_t phyRate,

                       uint32_t m, uint32_t dfree,

                       uint32_t adFree, uint32_t adFreePlusOne) const;

};

} // namespace ns3

#endif /* ERROR_RATE_MODEL_H */