/*
 * Copyright (c) 2011 The Boeing Company
 *
 * 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: Gary Pei <guangyu.pei@boeing.com>
 */
#ifndef LR_WPAN_SPECTRUM_VALUE_HELPER_H
#define LR_WPAN_SPECTRUM_VALUE_HELPER_H

#include <ns3/ptr.h>

namespace ns3
{

class SpectrumValue;

/**
 * \ingroup lr-wpan
 *
 * \brief This class defines all functions to create spectrum model for LrWpan
 */
class LrWpanSpectrumValueHelper
{
  public:
    LrWpanSpectrumValueHelper();
    virtual ~LrWpanSpectrumValueHelper();

    /**
     * \brief create spectrum value
     * \param txPower the power transmission in dBm
     * \param channel the channel number per IEEE802.15.4
     * \return a Ptr to a newly created SpectrumValue instance
     */
    Ptr<SpectrumValue> CreateTxPowerSpectralDensity(double txPower, uint32_t channel);

    /**
     * \brief create spectrum value for noise
     * \param channel the channel number per IEEE802.15.4
     * \return a Ptr to a newly created SpectrumValue instance
     */
    Ptr<SpectrumValue> CreateNoisePowerSpectralDensity(uint32_t channel);

    /**
     * \brief total average power of the signal is the integral of the PSD using
     * the limits of the given channel
     * \param psd spectral density
     * \param channel the channel number per IEEE802.15.4
     * \return total power (using composite trap. rule to numerally integrate)
     */
    static double TotalAvgPower(Ptr<const SpectrumValue> psd, uint32_t channel);

  private:
    /**
     * A scaling factor for the noise power.
     */
    double m_noiseFactor;
};

} // namespace ns3

#endif /*  LR_WPAN_SPECTRUM_VALUE_HELPER_H */
