tdmt-ff-mac-scheduler.cc

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/* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
/*
 * Copyright (c) 2011 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>  // original version
 * Modification: Dizhi Zhou <dizhi.zhou@gmail.com>    // modify codes related to downlink scheduler
 */

#include <ns3/log.h>
#include <ns3/pointer.h>
#include <ns3/math.h>

#include <ns3/simulator.h>
#include <ns3/lte-amc.h>
#include <ns3/tdmt-ff-mac-scheduler.h>
#include <ns3/lte-vendor-specific-parameters.h>

NS_LOG_COMPONENT_DEFINE ("TdMtFfMacScheduler");

// value for SINR outside the range defined by LTE, used to indicate that there
// is no CQI for this element
#define NO_SINR -5000

namespace ns3 {

int TdMtType0AllocationRbg[4] = {
  10,       // RGB size 1
  26,       // RGB size 2
  63,       // RGB size 3
  110       // RGB size 4
};  // see table 7.1.6.1-1 of 36.213


NS_OBJECT_ENSURE_REGISTERED (TdMtFfMacScheduler);



class TdMtSchedulerMemberCschedSapProvider : public FfMacCschedSapProvider
{
public:
  TdMtSchedulerMemberCschedSapProvider (TdMtFfMacScheduler* scheduler);

  // inherited from FfMacCschedSapProvider
  virtual void CschedCellConfigReq (const struct CschedCellConfigReqParameters& params);
  virtual void CschedUeConfigReq (const struct CschedUeConfigReqParameters& params);
  virtual void CschedLcConfigReq (const struct CschedLcConfigReqParameters& params);
  virtual void CschedLcReleaseReq (const struct CschedLcReleaseReqParameters& params);
  virtual void CschedUeReleaseReq (const struct CschedUeReleaseReqParameters& params);

private:
  TdMtSchedulerMemberCschedSapProvider ();
  TdMtFfMacScheduler* m_scheduler;
};

TdMtSchedulerMemberCschedSapProvider::TdMtSchedulerMemberCschedSapProvider ()
{
}

TdMtSchedulerMemberCschedSapProvider::TdMtSchedulerMemberCschedSapProvider (TdMtFfMacScheduler* scheduler) : m_scheduler (scheduler)
{
}


void
TdMtSchedulerMemberCschedSapProvider::CschedCellConfigReq (const struct CschedCellConfigReqParameters& params)
{
  m_scheduler->DoCschedCellConfigReq (params);
}

void
TdMtSchedulerMemberCschedSapProvider::CschedUeConfigReq (const struct CschedUeConfigReqParameters& params)
{
  m_scheduler->DoCschedUeConfigReq (params);
}


void
TdMtSchedulerMemberCschedSapProvider::CschedLcConfigReq (const struct CschedLcConfigReqParameters& params)
{
  m_scheduler->DoCschedLcConfigReq (params);
}

void
TdMtSchedulerMemberCschedSapProvider::CschedLcReleaseReq (const struct CschedLcReleaseReqParameters& params)
{
  m_scheduler->DoCschedLcReleaseReq (params);
}

void
TdMtSchedulerMemberCschedSapProvider::CschedUeReleaseReq (const struct CschedUeReleaseReqParameters& params)
{
  m_scheduler->DoCschedUeReleaseReq (params);
}




class TdMtSchedulerMemberSchedSapProvider : public FfMacSchedSapProvider
{
public:
  TdMtSchedulerMemberSchedSapProvider (TdMtFfMacScheduler* scheduler);

  // inherited from FfMacSchedSapProvider
  virtual void SchedDlRlcBufferReq (const struct SchedDlRlcBufferReqParameters& params);
  virtual void SchedDlPagingBufferReq (const struct SchedDlPagingBufferReqParameters& params);
  virtual void SchedDlMacBufferReq (const struct SchedDlMacBufferReqParameters& params);
  virtual void SchedDlTriggerReq (const struct SchedDlTriggerReqParameters& params);
  virtual void SchedDlRachInfoReq (const struct SchedDlRachInfoReqParameters& params);
  virtual void SchedDlCqiInfoReq (const struct SchedDlCqiInfoReqParameters& params);
  virtual void SchedUlTriggerReq (const struct SchedUlTriggerReqParameters& params);
  virtual void SchedUlNoiseInterferenceReq (const struct SchedUlNoiseInterferenceReqParameters& params);
  virtual void SchedUlSrInfoReq (const struct SchedUlSrInfoReqParameters& params);
  virtual void SchedUlMacCtrlInfoReq (const struct SchedUlMacCtrlInfoReqParameters& params);
  virtual void SchedUlCqiInfoReq (const struct SchedUlCqiInfoReqParameters& params);


private:
  TdMtSchedulerMemberSchedSapProvider ();
  TdMtFfMacScheduler* m_scheduler;
};



TdMtSchedulerMemberSchedSapProvider::TdMtSchedulerMemberSchedSapProvider ()
{
}


TdMtSchedulerMemberSchedSapProvider::TdMtSchedulerMemberSchedSapProvider (TdMtFfMacScheduler* scheduler)
  : m_scheduler (scheduler)
{
}

void
TdMtSchedulerMemberSchedSapProvider::SchedDlRlcBufferReq (const struct SchedDlRlcBufferReqParameters& params)
{
  m_scheduler->DoSchedDlRlcBufferReq (params);
}

void
TdMtSchedulerMemberSchedSapProvider::SchedDlPagingBufferReq (const struct SchedDlPagingBufferReqParameters& params)
{
  m_scheduler->DoSchedDlPagingBufferReq (params);
}

void
TdMtSchedulerMemberSchedSapProvider::SchedDlMacBufferReq (const struct SchedDlMacBufferReqParameters& params)
{
  m_scheduler->DoSchedDlMacBufferReq (params);
}

void
TdMtSchedulerMemberSchedSapProvider::SchedDlTriggerReq (const struct SchedDlTriggerReqParameters& params)
{
  m_scheduler->DoSchedDlTriggerReq (params);
}

void
TdMtSchedulerMemberSchedSapProvider::SchedDlRachInfoReq (const struct SchedDlRachInfoReqParameters& params)
{
  m_scheduler->DoSchedDlRachInfoReq (params);
}

void
TdMtSchedulerMemberSchedSapProvider::SchedDlCqiInfoReq (const struct SchedDlCqiInfoReqParameters& params)
{
  m_scheduler->DoSchedDlCqiInfoReq (params);
}

void
TdMtSchedulerMemberSchedSapProvider::SchedUlTriggerReq (const struct SchedUlTriggerReqParameters& params)
{
  m_scheduler->DoSchedUlTriggerReq (params);
}

void
TdMtSchedulerMemberSchedSapProvider::SchedUlNoiseInterferenceReq (const struct SchedUlNoiseInterferenceReqParameters& params)
{
  m_scheduler->DoSchedUlNoiseInterferenceReq (params);
}

void
TdMtSchedulerMemberSchedSapProvider::SchedUlSrInfoReq (const struct SchedUlSrInfoReqParameters& params)
{
  m_scheduler->DoSchedUlSrInfoReq (params);
}

void
TdMtSchedulerMemberSchedSapProvider::SchedUlMacCtrlInfoReq (const struct SchedUlMacCtrlInfoReqParameters& params)
{
  m_scheduler->DoSchedUlMacCtrlInfoReq (params);
}

void
TdMtSchedulerMemberSchedSapProvider::SchedUlCqiInfoReq (const struct SchedUlCqiInfoReqParameters& params)
{
  m_scheduler->DoSchedUlCqiInfoReq (params);
}





TdMtFfMacScheduler::TdMtFfMacScheduler ()
  :   m_cschedSapUser (0),
    m_schedSapUser (0),
    m_nextRntiUl (0)
{
  m_amc = CreateObject <LteAmc> ();
  m_cschedSapProvider = new TdMtSchedulerMemberCschedSapProvider (this);
  m_schedSapProvider = new TdMtSchedulerMemberSchedSapProvider (this);
}

TdMtFfMacScheduler::~TdMtFfMacScheduler ()
{
  NS_LOG_FUNCTION (this);
}

void
TdMtFfMacScheduler::DoDispose ()
{
  NS_LOG_FUNCTION (this);
  delete m_cschedSapProvider;
  delete m_schedSapProvider;
}

TypeId
TdMtFfMacScheduler::GetTypeId (void)
{
  static TypeId tid = TypeId ("ns3::TdMtFfMacScheduler")
    .SetParent<FfMacScheduler> ()
    .AddConstructor<TdMtFfMacScheduler> ()
    .AddAttribute ("CqiTimerThreshold",
                   "The number of TTIs a CQI is valid (default 1000 - 1 sec.)",
                   UintegerValue (1000),
                   MakeUintegerAccessor (&TdMtFfMacScheduler::m_cqiTimersThreshold),
                   MakeUintegerChecker<uint32_t> ())
    ;
  return tid;
}



void
TdMtFfMacScheduler::SetFfMacCschedSapUser (FfMacCschedSapUser* s)
{
  m_cschedSapUser = s;
}

void
TdMtFfMacScheduler::SetFfMacSchedSapUser (FfMacSchedSapUser* s)
{
  m_schedSapUser = s;
}

FfMacCschedSapProvider*
TdMtFfMacScheduler::GetFfMacCschedSapProvider ()
{
  return m_cschedSapProvider;
}

FfMacSchedSapProvider*
TdMtFfMacScheduler::GetFfMacSchedSapProvider ()
{
  return m_schedSapProvider;
}

void
TdMtFfMacScheduler::DoCschedCellConfigReq (const struct FfMacCschedSapProvider::CschedCellConfigReqParameters& params)
{
  NS_LOG_FUNCTION (this);
  // Read the subset of parameters used
  m_cschedCellConfig = params;
  FfMacCschedSapUser::CschedUeConfigCnfParameters cnf;
  cnf.m_result = SUCCESS;
  m_cschedSapUser->CschedUeConfigCnf (cnf);
  return;
}

void
TdMtFfMacScheduler::DoCschedUeConfigReq (const struct FfMacCschedSapProvider::CschedUeConfigReqParameters& params)
{
  NS_LOG_FUNCTION (this << " RNTI " << params.m_rnti << " txMode " << (uint16_t)params.m_transmissionMode);
  std::map <uint16_t,uint8_t>::iterator it = m_uesTxMode.find (params.m_rnti);
  if (it == m_uesTxMode.end ())
    {
      m_uesTxMode.insert (std::pair <uint16_t, double> (params.m_rnti, params.m_transmissionMode));
    }
  else
    {
      (*it).second = params.m_transmissionMode;
    }
  return;
}

void
TdMtFfMacScheduler::DoCschedLcConfigReq (const struct FfMacCschedSapProvider::CschedLcConfigReqParameters& params)
{
  NS_LOG_FUNCTION (this << " New LC, rnti: "  << params.m_rnti);

  std::set<uint16_t>::iterator it;

  for (uint16_t i = 0; i < params.m_logicalChannelConfigList.size (); i++)
    {
      it = m_flowStatsDl.find (params.m_rnti);

      if (it == m_flowStatsDl.end ())
        {
          m_flowStatsDl.insert (params.m_rnti);
          m_flowStatsUl.insert (params.m_rnti);
        }
      else
        {
          NS_LOG_ERROR ("RNTI already exists");
        }

    }

  return;
}


void
TdMtFfMacScheduler::DoCschedLcReleaseReq (const struct FfMacCschedSapProvider::CschedLcReleaseReqParameters& params)
{
  NS_FATAL_ERROR ("unimplemented");
  return;
}

void
TdMtFfMacScheduler::DoCschedUeReleaseReq (const struct FfMacCschedSapProvider::CschedUeReleaseReqParameters& params)
{
  NS_FATAL_ERROR ("unimplemented");
  return;
}


void
TdMtFfMacScheduler::DoSchedDlRlcBufferReq (const struct FfMacSchedSapProvider::SchedDlRlcBufferReqParameters& params)
{
  NS_LOG_FUNCTION (this << params.m_rnti << (uint32_t) params.m_logicalChannelIdentity);
  // API generated by RLC for updating RLC parameters on a LC (tx and retx queues)

  std::map <LteFlowId_t, FfMacSchedSapProvider::SchedDlRlcBufferReqParameters>::iterator it;

  LteFlowId_t flow (params.m_rnti, params.m_logicalChannelIdentity);

  it =  m_rlcBufferReq.find (flow);

  if (it == m_rlcBufferReq.end ())
    {
      m_rlcBufferReq.insert (std::pair <LteFlowId_t, FfMacSchedSapProvider::SchedDlRlcBufferReqParameters> (flow, params));
    }
  else
    {
      (*it).second = params;
    }

  return;
}

void
TdMtFfMacScheduler::DoSchedDlPagingBufferReq (const struct FfMacSchedSapProvider::SchedDlPagingBufferReqParameters& params)
{
  NS_FATAL_ERROR ("unimplemented");
  return;
}

void
TdMtFfMacScheduler::DoSchedDlMacBufferReq (const struct FfMacSchedSapProvider::SchedDlMacBufferReqParameters& params)
{
  NS_FATAL_ERROR ("unimplemented");
  return;
}

int
TdMtFfMacScheduler::GetRbgSize (int dlbandwidth)
{
  for (int i = 0; i < 4; i++)
    {
      if (dlbandwidth < TdMtType0AllocationRbg[i])
        {
          return (i + 1);
        }
    }

  return (-1);
}


int 
TdMtFfMacScheduler::LcActivePerFlow (uint16_t rnti)
{
  std::map <LteFlowId_t, FfMacSchedSapProvider::SchedDlRlcBufferReqParameters>::iterator it;
  int lcActive = 0;
  for (it = m_rlcBufferReq.begin (); it != m_rlcBufferReq.end (); it++)
    {
      if (((*it).first.m_rnti == rnti) && (((*it).second.m_rlcTransmissionQueueSize > 0)
                                           || ((*it).second.m_rlcRetransmissionQueueSize > 0)
                                           || ((*it).second.m_rlcStatusPduSize > 0) ))
        {
          lcActive++;
        }
      if ((*it).first.m_rnti > rnti)
        {
          break;
        }
    }
  return (lcActive);

}


void
TdMtFfMacScheduler::DoSchedDlTriggerReq (const struct FfMacSchedSapProvider::SchedDlTriggerReqParameters& params)
{
  NS_LOG_FUNCTION (this << " Frame no. " << (params.m_sfnSf >> 4) << " subframe no. " << (0xF & params.m_sfnSf));
  // API generated by RLC for triggering the scheduling of a DL subframe


  // evaluate the relative channel quality indicator for each UE per each RBG 
  // (since we are using allocation type 0 the small unit of allocation is RBG)
  // Resource allocation type 0 (see sec 7.1.6.1 of 36.213)
  
  RefreshDlCqiMaps ();
  
  int rbgSize = GetRbgSize (m_cschedCellConfig.m_dlBandwidth);
  int rbgNum = m_cschedCellConfig.m_dlBandwidth / rbgSize;
  std::map <uint16_t, std::vector <uint16_t> > allocationMap;
  std::set <uint16_t>::iterator it;
  std::set <uint16_t>::iterator itMax = m_flowStatsDl.end ();
  double metricMax = 0.0;
  for (it = m_flowStatsDl.begin (); it != m_flowStatsDl.end (); it++)
    {
      std::map <uint16_t,uint8_t>::iterator itCqi;
      itCqi = m_p10CqiRxed.find ((*it));
      std::map <uint16_t,uint8_t>::iterator itTxMode;
      itTxMode = m_uesTxMode.find ((*it));
      if (itTxMode == m_uesTxMode.end ())
        {
          NS_FATAL_ERROR ("No Transmission Mode info on user " << (*it));
        }
      int nLayer = TransmissionModesLayers::TxMode2LayerNum ((*itTxMode).second);
      uint8_t wbCqi = 0;
      if (itCqi == m_p10CqiRxed.end())
        {
          wbCqi = 1; // start with lowest value
        }
      else
        {
          wbCqi = (*itCqi).second;
        }

      if (wbCqi > 0)
        {
          if (LcActivePerFlow (*it) > 0)
            {
              // this UE has data to transmit
              double achievableRate = 0.0;
              for (uint8_t k = 0; k < nLayer; k++) 
                {
                  uint8_t mcs = 0; 
                  mcs = m_amc->GetMcsFromCqi (wbCqi);
                  achievableRate += ((m_amc->GetTbSizeFromMcs (mcs, rbgSize) / 8) / 0.001); // = TB size / TTI
                }

             double metric = achievableRate;

             if (metric > metricMax)
               {
                 metricMax = metric;
                 itMax = it;
               }
           }
        } // end of wbCqi
    } // end for m_flowStatsDl

  if (itMax == m_flowStatsDl.end ())
    {
      // no UE available for downlink 
      return;
    }
  else
    {
      // assign all RBGs to this UE
      std::vector <uint16_t> tempMap;
      for (int i = 0; i < rbgNum; i++)
        {
          tempMap.push_back (i);
        }
      allocationMap.insert (std::pair <uint16_t, std::vector <uint16_t> > ((*itMax), tempMap));
    }

  // generate the transmission opportunities by grouping the RBGs of the same RNTI and
  // creating the correspondent DCIs
  FfMacSchedSapUser::SchedDlConfigIndParameters ret;
  std::map <uint16_t, std::vector <uint16_t> >::iterator itMap = allocationMap.begin ();
  while (itMap != allocationMap.end ())
    {
      // create new BuildDataListElement_s for this LC
      BuildDataListElement_s newEl;
      newEl.m_rnti = (*itMap).first;
      // create the DlDciListElement_s
      DlDciListElement_s newDci;
      std::vector <struct RlcPduListElement_s> newRlcPduLe;
      newDci.m_rnti = (*itMap).first;

      uint16_t lcActives = LcActivePerFlow ((*itMap).first);
      std::map <uint16_t,uint8_t>::iterator itCqi;
      itCqi = m_p10CqiRxed.find((*itMap).first);
      std::map <uint16_t,uint8_t>::iterator itTxMode;
      itTxMode = m_uesTxMode.find ((*itMap).first);
      if (itTxMode == m_uesTxMode.end ())
        {
          NS_FATAL_ERROR ("No Transmission Mode info on user " << (*itMap).first);
        }
      int nLayer = TransmissionModesLayers::TxMode2LayerNum ((*itTxMode).second);
      for (uint8_t j = 0; j < nLayer; j++)
        {
          if (itCqi == m_p10CqiRxed.end ())
            {
              newDci.m_mcs.push_back (0); // no info on this user -> lowest MCS
            }
          else
            {
              newDci.m_mcs.push_back ( m_amc->GetMcsFromCqi ((*itCqi).second) );
            }
          // allocate all RBGs to this UE
          int tbSize = (m_amc->GetTbSizeFromMcs (newDci.m_mcs.at (j), rbgNum * rbgSize) / 8); // (size of TB in bytes according to table 7.1.7.2.1-1 of 36.213)
          newDci.m_tbsSize.push_back (tbSize);
        }

      newDci.m_resAlloc = 0;  // only allocation type 0 at this stage
      newDci.m_rbBitmap = 0; // TBD (32 bit bitmap see 7.1.6 of 36.213)
      uint32_t rbgMask = 0;
      for (uint16_t k = 0; k < (*itMap).second.size (); k++)
        {
          rbgMask = rbgMask + (0x1 << (*itMap).second.at (k));
        }
      newDci.m_rbBitmap = rbgMask; // (32 bit bitmap see 7.1.6 of 36.213)

      // create the rlc PDUs -> equally divide resources among actives LCs
      std::map <LteFlowId_t, FfMacSchedSapProvider::SchedDlRlcBufferReqParameters>::iterator itBufReq;
      for (itBufReq = m_rlcBufferReq.begin (); itBufReq != m_rlcBufferReq.end (); itBufReq++)
        {
          if (((*itBufReq).first.m_rnti == (*itMap).first) &&
            (((*itBufReq).second.m_rlcTransmissionQueueSize > 0)
              || ((*itBufReq).second.m_rlcRetransmissionQueueSize > 0)
              || ((*itBufReq).second.m_rlcStatusPduSize > 0) ))
            {
              for (uint8_t j = 0; j < nLayer; j++)
                {
                  RlcPduListElement_s newRlcEl;
                  newRlcEl.m_logicalChannelIdentity = (*itBufReq).first.m_lcId;
                  newRlcEl.m_size = newDci.m_tbsSize.at (j) / lcActives;
                  newRlcPduLe.push_back (newRlcEl);
                  UpdateDlRlcBufferInfo (newDci.m_rnti, newRlcEl.m_logicalChannelIdentity, newRlcEl.m_size);
                }
            }
          if ((*itBufReq).first.m_rnti > (*itMap).first)
            {
              break;
            }
        }
      newDci.m_ndi.push_back (1); // TBD (new data indicator)
      newDci.m_rv.push_back (0); // TBD (redundancy version)

      newEl.m_dci = newDci;
      // ...more parameters -> ingored in this version

      newEl.m_rlcPduList.push_back (newRlcPduLe);
      ret.m_buildDataList.push_back (newEl);


      itMap++;
    } // end while allocation
  ret.m_nrOfPdcchOfdmSymbols = 1;   // TODO: check correct value according the DCIs txed

  m_schedSapUser->SchedDlConfigInd (ret);
 
  return;
}

void
TdMtFfMacScheduler::DoSchedDlRachInfoReq (const struct FfMacSchedSapProvider::SchedDlRachInfoReqParameters& params)
{
  NS_FATAL_ERROR ("unimplemented");
  return;
}

void
TdMtFfMacScheduler::DoSchedDlCqiInfoReq (const struct FfMacSchedSapProvider::SchedDlCqiInfoReqParameters& params)
{
  NS_LOG_FUNCTION (this);

  for (unsigned int i = 0; i < params.m_cqiList.size (); i++)
    {
      if ( params.m_cqiList.at (i).m_cqiType == CqiListElement_s::P10 )
        {
          // wideband CQI reporting
          std::map <uint16_t,uint8_t>::iterator it;
          uint16_t rnti = params.m_cqiList.at (i).m_rnti;
          it = m_p10CqiRxed.find (rnti);
          if (it == m_p10CqiRxed.end ())
            {
              // create the new entry
              m_p10CqiRxed.insert ( std::pair<uint16_t, uint8_t > (rnti, params.m_cqiList.at (i).m_wbCqi.at (0)) ); // only codeword 0 at this stage (SISO)
              // generate correspondent timer
              m_p10CqiTimers.insert ( std::pair<uint16_t, uint32_t > (rnti, m_cqiTimersThreshold));
            }
          else
            {
              // update the CQI value and refresh correspondent timer
              (*it).second = params.m_cqiList.at (i).m_wbCqi.at (0);
              // update correspondent timer
              std::map <uint16_t,uint32_t>::iterator itTimers;
              itTimers = m_p10CqiTimers.find (rnti);
              (*itTimers).second = m_cqiTimersThreshold;
            }
        }
      else if ( params.m_cqiList.at (i).m_cqiType == CqiListElement_s::A30 )
        {
          // subband CQI reporting high layer configured
          std::map <uint16_t,SbMeasResult_s>::iterator it;
          uint16_t rnti = params.m_cqiList.at (i).m_rnti;
          it = m_a30CqiRxed.find (rnti);
          if (it == m_a30CqiRxed.end ())
            {
              // create the new entry
              m_a30CqiRxed.insert ( std::pair<uint16_t, SbMeasResult_s > (rnti, params.m_cqiList.at (i).m_sbMeasResult) );
              m_a30CqiTimers.insert ( std::pair<uint16_t, uint32_t > (rnti, m_cqiTimersThreshold));
            }
          else
            {
              // update the CQI value and refresh correspondent timer
              (*it).second = params.m_cqiList.at (i).m_sbMeasResult;
              std::map <uint16_t,uint32_t>::iterator itTimers;
              itTimers = m_a30CqiTimers.find (rnti);
              (*itTimers).second = m_cqiTimersThreshold;
            }
        }
      else
        {
          NS_LOG_ERROR (this << " CQI type unknown");
        }
    }

  return;
}


double
TdMtFfMacScheduler::EstimateUlSinr (uint16_t rnti, uint16_t rb)
{
  std::map <uint16_t, std::vector <double> >::iterator itCqi = m_ueCqi.find (rnti);
  if (itCqi == m_ueCqi.end ())
    {
      // no cqi info about this UE
      return (NO_SINR);

    }
  else
    {
      // take the average SINR value among the available
      double sinrSum = 0;
      int sinrNum = 0;
      for (uint32_t i = 0; i < m_cschedCellConfig.m_ulBandwidth; i++)
        {
          double sinr = (*itCqi).second.at (i);
          if (sinr != NO_SINR)
            {
              sinrSum += sinr;
              sinrNum++;
            }
        }
      double estimatedSinr = sinrSum / (double)sinrNum;
      // store the value
      (*itCqi).second.at (rb) = estimatedSinr;
      return (estimatedSinr);
    }
}

void
TdMtFfMacScheduler::DoSchedUlTriggerReq (const struct FfMacSchedSapProvider::SchedUlTriggerReqParameters& params)
{
  NS_LOG_FUNCTION (this << " UL - Frame no. " << (params.m_sfnSf >> 4) << " subframe no. " << (0xF & params.m_sfnSf));
 
  RefreshUlCqiMaps ();

  std::map <uint16_t,uint32_t>::iterator it; 
  int nflows = 0;

  for (it = m_ceBsrRxed.begin (); it != m_ceBsrRxed.end (); it++)
    {
      // remove old entries of this UE-LC
      if ((*it).second > 0)
        {
          nflows++;
        }
    }

  if (nflows == 0)
    {
      return ; // no flows to be scheduled
    }


  // Divide the resource equally among the active users
  int rbPerFlow = m_cschedCellConfig.m_ulBandwidth / nflows;
  if (rbPerFlow == 0)
    {
      rbPerFlow = 1;              // at least 1 rbg per flow (till available resource)
    }
  int rbAllocated = 0;

  FfMacSchedSapUser::SchedUlConfigIndParameters ret;
  std::vector <uint16_t> rbgAllocationMap;
  if (m_nextRntiUl != 0)
    {
      for (it = m_ceBsrRxed.begin (); it != m_ceBsrRxed.end (); it++)
        {
          if ((*it).first == m_nextRntiUl)
            {
              break;
            }
        }
      if (it == m_ceBsrRxed.end ())
        {
          NS_LOG_ERROR (this << " no user found");
        }
    }
  else
    {
      it = m_ceBsrRxed.begin ();
      m_nextRntiUl = (*it).first;
    }
  do
    {
      if (rbAllocated + rbPerFlow > m_cschedCellConfig.m_ulBandwidth)
        {
          // limit to physical resources last resource assignment
          rbPerFlow = m_cschedCellConfig.m_ulBandwidth - rbAllocated;
        }
     
      UlDciListElement_s uldci;
      uldci.m_rnti = (*it).first;
      uldci.m_rbStart = rbAllocated;
      uldci.m_rbLen = rbPerFlow;
      std::map <uint16_t, std::vector <double> >::iterator itCqi = m_ueCqi.find ((*it).first);
      int cqi = 0;
      if (itCqi == m_ueCqi.end ())
        {
          // no cqi info about this UE
          uldci.m_mcs = 0; // MCS 0 -> UL-AMC TBD
        }
      else
        {
          // take the lowest CQI value (worst RB)
          double minSinr = (*itCqi).second.at (uldci.m_rbStart);
          if (minSinr == NO_SINR)
            {
              minSinr = EstimateUlSinr ((*it).first, uldci.m_rbStart);
            }
          for (uint16_t i = uldci.m_rbStart; i < uldci.m_rbStart + uldci.m_rbLen; i++)
            {
              double sinr = (*itCqi).second.at (i);
              if (sinr == NO_SINR)
                {
                  sinr = EstimateUlSinr ((*it).first, i);
                }
              if ((*itCqi).second.at (i) < minSinr)
                {
                  minSinr = (*itCqi).second.at (i);
                }
            }

          // translate SINR -> cqi: WILD ACK: same as DL
          double s = log2 ( 1 + (
                                 std::pow (10, minSinr / 10 )  /
                                 ( (-std::log (5.0 * 0.00005 )) / 1.5) ));
          cqi = m_amc->GetCqiFromSpectralEfficiency (s);
          if (cqi == 0)
            {
              it++;
              if (it == m_ceBsrRxed.end ())
                {
                  // restart from the first
                  it = m_ceBsrRxed.begin ();
                }
              continue; // CQI == 0 means "out of range" (see table 7.2.3-1 of 36.213)
            }
          uldci.m_mcs = m_amc->GetMcsFromCqi (cqi);

        }
      
      rbAllocated += rbPerFlow;
      // store info on allocation for managing ul-cqi interpretation
      for (int i = 0; i < rbPerFlow; i++)
        {
          rbgAllocationMap.push_back ((*it).first);
        }
      uldci.m_tbSize = (m_amc->GetTbSizeFromMcs (uldci.m_mcs, rbPerFlow) / 8);
      NS_LOG_DEBUG (this << " UE " << (*it).first << " startPRB " << (uint32_t)uldci.m_rbStart << " nPRB " << (uint32_t)uldci.m_rbLen << " CQI " << cqi << " MCS " << (uint32_t)uldci.m_mcs << " TBsize " << uldci.m_tbSize << " RbAlloc " << rbAllocated);
      UpdateUlRlcBufferInfo (uldci.m_rnti, uldci.m_tbSize);
      uldci.m_ndi = 1;
      uldci.m_cceIndex = 0;
      uldci.m_aggrLevel = 1;
      uldci.m_ueTxAntennaSelection = 3; // antenna selection OFF
      uldci.m_hopping = false;
      uldci.m_n2Dmrs = 0;
      uldci.m_tpc = 0; // no power control
      uldci.m_cqiRequest = false; // only period CQI at this stage
      uldci.m_ulIndex = 0; // TDD parameter
      uldci.m_dai = 1; // TDD parameter
      uldci.m_freqHopping = 0;
      uldci.m_pdcchPowerOffset = 0; // not used
      ret.m_dciList.push_back (uldci);


      it++;
      if (it == m_ceBsrRxed.end ())
        {
          // restart from the first
          it = m_ceBsrRxed.begin ();
        }
      if (rbAllocated == m_cschedCellConfig.m_ulBandwidth)
        {
          // Stop allocation: no more PRBs
          m_nextRntiUl = (*it).first;
          break;
        }
    }
  while ((*it).first != m_nextRntiUl);


  m_allocationMaps.insert (std::pair <uint16_t, std::vector <uint16_t> > (params.m_sfnSf, rbgAllocationMap));
  m_schedSapUser->SchedUlConfigInd (ret);
  return;
}

void
TdMtFfMacScheduler::DoSchedUlNoiseInterferenceReq (const struct FfMacSchedSapProvider::SchedUlNoiseInterferenceReqParameters& params)
{
  NS_FATAL_ERROR ("unimplemented");
  return;
}

void
TdMtFfMacScheduler::DoSchedUlSrInfoReq (const struct FfMacSchedSapProvider::SchedUlSrInfoReqParameters& params)
{
  NS_FATAL_ERROR ("unimplemented");
  return;
}

void
TdMtFfMacScheduler::DoSchedUlMacCtrlInfoReq (const struct FfMacSchedSapProvider::SchedUlMacCtrlInfoReqParameters& params)
{
  NS_LOG_FUNCTION (this);

  std::map <uint16_t,uint32_t>::iterator it;
  
  for (unsigned int i = 0; i < params.m_macCeList.size (); i++)
  {
    if ( params.m_macCeList.at (i).m_macCeType == MacCeListElement_s::BSR )
    {
      // buffer status report
      // note that we only consider LCG 0, the other three LCGs are neglected
      // this is consistent with the assumption in LteUeMac that the first LCG gathers all LCs
      uint16_t rnti = params.m_macCeList.at (i).m_rnti;
      it = m_ceBsrRxed.find (rnti);
      if (it == m_ceBsrRxed.end ())
      {
        // create the new entry
        uint8_t bsrId = params.m_macCeList.at (i).m_macCeValue.m_bufferStatus.at (0);
        int buffer = BufferSizeLevelBsr::BsrId2BufferSize (bsrId);
        m_ceBsrRxed.insert ( std::pair<uint16_t, uint32_t > (rnti, buffer)); 
      }
      else
      {
        // update the buffer size value
        (*it).second = BufferSizeLevelBsr::BsrId2BufferSize (params.m_macCeList.at (i).m_macCeValue.m_bufferStatus.at (0));
      }
    }
  }
  
  return;
}

void
TdMtFfMacScheduler::DoSchedUlCqiInfoReq (const struct FfMacSchedSapProvider::SchedUlCqiInfoReqParameters& params)
{
  NS_LOG_FUNCTION (this);
  // retrieve the allocation for this subframe
  switch (m_ulCqiFilter)
    {
      case FfMacScheduler::SRS_UL_CQI:
        {
          // filter all the CQIs that are not SRS based
          if (params.m_ulCqi.m_type!=UlCqi_s::SRS)
              {
                return;
              }
        }
      break;
      case FfMacScheduler::PUSCH_UL_CQI:
        {
          // filter all the CQIs that are not SRS based
          if (params.m_ulCqi.m_type!=UlCqi_s::PUSCH)
            {
              return;
            }
        }
      case FfMacScheduler::ALL_UL_CQI:
      break;
      
      default:
        NS_FATAL_ERROR ("Unknown UL CQI type");
    }

  switch (params.m_ulCqi.m_type)
  {
    case UlCqi_s::PUSCH:
      {
        std::map <uint16_t, std::vector <uint16_t> >::iterator itMap;
        std::map <uint16_t, std::vector <double> >::iterator itCqi;
        itMap = m_allocationMaps.find (params.m_sfnSf);
        if (itMap == m_allocationMaps.end ())
          {
            NS_LOG_DEBUG (this << " Does not find info on allocation, size : " << m_allocationMaps.size ());
            return;
          }
        for (uint32_t i = 0; i < (*itMap).second.size (); i++)
          {
            // convert from fixed point notation Sxxxxxxxxxxx.xxx to double
      //       NS_LOG_INFO (this << " i " << i << " size " << params.m_ulCqi.m_sinr.size () << " mapSIze " << (*itMap).second.size ());
            double sinr = LteFfConverter::fpS11dot3toDouble (params.m_ulCqi.m_sinr.at (i));
            itCqi = m_ueCqi.find ((*itMap).second.at (i));
            if (itCqi == m_ueCqi.end ())
              {
                // create a new entry
                std::vector <double> newCqi;
                for (uint32_t j = 0; j < m_cschedCellConfig.m_ulBandwidth; j++)
                  {
                    if (i == j)
                      {
                        newCqi.push_back (sinr);
                      }
                    else
                      {
                        // initialize with NO_SINR value.
                        newCqi.push_back (NO_SINR);
                      }

                  }
                m_ueCqi.insert (std::pair <uint16_t, std::vector <double> > ((*itMap).second.at (i), newCqi));
                // generate correspondent timer
                m_ueCqiTimers.insert (std::pair <uint16_t, uint32_t > ((*itMap).second.at (i), m_cqiTimersThreshold));
              }
            else
              {
                // update the value
                (*itCqi).second.at (i) = sinr;
                // update correspondent timer
                std::map <uint16_t, uint32_t>::iterator itTimers;
                itTimers = m_ueCqiTimers.find ((*itMap).second.at (i));
                (*itTimers).second = m_cqiTimersThreshold;
                
              }

          }
        // remove obsolete info on allocation
        m_allocationMaps.erase (itMap);
      }
      break;
    case UlCqi_s::SRS:
      {
        // get the RNTI from vendor specific parameters
        uint16_t rnti = 0;
        NS_ASSERT (params.m_vendorSpecificList.size () > 0);
        for (uint16_t i = 0; i < params.m_vendorSpecificList.size (); i++)
          {
            if (params.m_vendorSpecificList.at (i).m_type == SRS_CQI_RNTI_VSP)
              {
                Ptr<SrsCqiRntiVsp> vsp = DynamicCast<SrsCqiRntiVsp> (params.m_vendorSpecificList.at (i).m_value);
                rnti = vsp->GetRnti ();
              }
          }
        std::map <uint16_t, std::vector <double> >::iterator itCqi;
        itCqi = m_ueCqi.find (rnti);
        if (itCqi == m_ueCqi.end ())
          {
            // create a new entry
            std::vector <double> newCqi;
            for (uint32_t j = 0; j < m_cschedCellConfig.m_ulBandwidth; j++)
            {
              double sinr = LteFfConverter::fpS11dot3toDouble (params.m_ulCqi.m_sinr.at (j));
              newCqi.push_back (sinr);
              NS_LOG_DEBUG (this << " RNTI " << rnti << " new SRS-CQI for RB  " << j << " value " << sinr);
              
            }
            m_ueCqi.insert (std::pair <uint16_t, std::vector <double> > (rnti, newCqi));
            // generate correspondent timer
            m_ueCqiTimers.insert (std::pair <uint16_t, uint32_t > (rnti, m_cqiTimersThreshold));
          }
        else
        {
          // update the values
          for (uint32_t j = 0; j < m_cschedCellConfig.m_ulBandwidth; j++)
            {
              double sinr = LteFfConverter::fpS11dot3toDouble (params.m_ulCqi.m_sinr.at (j));
              (*itCqi).second.at (j) = sinr;
              NS_LOG_DEBUG (this << " RNTI " << rnti << " update SRS-CQI for RB  " << j << " value " << sinr);
            }
          // update correspondent timer
          std::map <uint16_t, uint32_t>::iterator itTimers;
          itTimers = m_ueCqiTimers.find (rnti);
          (*itTimers).second = m_cqiTimersThreshold;
          
        }
        
        
      }
      break;
    case UlCqi_s::PUCCH_1:
    case UlCqi_s::PUCCH_2:
    case UlCqi_s::PRACH:
      {
        NS_FATAL_ERROR ("TdMtFfMacScheduler supports only PUSCH and SRS UL-CQIs");
      }
      break;
    default:
      NS_FATAL_ERROR ("Unknown type of UL-CQI");
  }
  return;
}

void
TdMtFfMacScheduler::RefreshDlCqiMaps(void)
{
  // refresh DL CQI P01 Map
  std::map <uint16_t,uint32_t>::iterator itP10 = m_p10CqiTimers.begin ();
  while (itP10!=m_p10CqiTimers.end ())
    {
//       NS_LOG_INFO (this << " P10-CQI for user " << (*itP10).first << " is " << (uint32_t)(*itP10).second << " thr " << (uint32_t)m_cqiTimersThreshold);
      if ((*itP10).second == 0)
        {
          // delete correspondent entries
          std::map <uint16_t,uint8_t>::iterator itMap = m_p10CqiRxed.find ((*itP10).first);
          NS_ASSERT_MSG (itMap != m_p10CqiRxed.end (), " Does not find CQI report for user " << (*itP10).first);
          NS_LOG_INFO (this << " P10-CQI exired for user " << (*itP10).first);
          m_p10CqiRxed.erase (itMap);
          std::map <uint16_t,uint32_t>::iterator temp = itP10;
          itP10++;
          m_p10CqiTimers.erase (temp);
        }
      else
        {
          (*itP10).second--;
          itP10++;
        }
    }
  
  // refresh DL CQI A30 Map
  std::map <uint16_t,uint32_t>::iterator itA30 = m_a30CqiTimers.begin ();
  while (itA30!=m_a30CqiTimers.end ())
    {
//       NS_LOG_INFO (this << " A30-CQI for user " << (*itA30).first << " is " << (uint32_t)(*itA30).second << " thr " << (uint32_t)m_cqiTimersThreshold);
      if ((*itA30).second == 0)
        {
          // delete correspondent entries
          std::map <uint16_t,SbMeasResult_s>::iterator itMap = m_a30CqiRxed.find ((*itA30).first);
          NS_ASSERT_MSG (itMap != m_a30CqiRxed.end (), " Does not find CQI report for user " << (*itA30).first);
          NS_LOG_INFO (this << " A30-CQI exired for user " << (*itA30).first);
          m_a30CqiRxed.erase (itMap);
          std::map <uint16_t,uint32_t>::iterator temp = itA30;
          itA30++;
          m_a30CqiTimers.erase (temp);
        }
      else
        {
          (*itA30).second--;
          itA30++;
        }
    }
    
    return;
}


void
TdMtFfMacScheduler::RefreshUlCqiMaps(void)
{
  // refresh UL CQI  Map
  std::map <uint16_t,uint32_t>::iterator itUl = m_ueCqiTimers.begin ();
  while (itUl!=m_ueCqiTimers.end ())
    {
//       NS_LOG_INFO (this << " UL-CQI for user " << (*itUl).first << " is " << (uint32_t)(*itUl).second << " thr " << (uint32_t)m_cqiTimersThreshold);
      if ((*itUl).second == 0)
        {
          // delete correspondent entries
          std::map <uint16_t, std::vector <double> >::iterator itMap = m_ueCqi.find ((*itUl).first);
          NS_ASSERT_MSG (itMap != m_ueCqi.end (), " Does not find CQI report for user " << (*itUl).first);
          NS_LOG_INFO (this << " UL-CQI exired for user " << (*itUl).first);
          (*itMap).second.clear ();
          m_ueCqi.erase (itMap);
          std::map <uint16_t,uint32_t>::iterator temp = itUl;
          itUl++;
          m_ueCqiTimers.erase (temp);
        }
      else
        {
          (*itUl).second--;
          itUl++;
        }
    }
    
    return;
}

void
TdMtFfMacScheduler::UpdateDlRlcBufferInfo (uint16_t rnti, uint8_t lcid, uint16_t size)
{
  size = size - 2; // remove the minimum RLC overhead
  std::map<LteFlowId_t, FfMacSchedSapProvider::SchedDlRlcBufferReqParameters>::iterator it;
  LteFlowId_t flow (rnti, lcid);
  it = m_rlcBufferReq.find (flow);
  if (it!=m_rlcBufferReq.end ())
    {
      // Update queues: RLC tx order Status, ReTx, Tx
      // Update status queue
      if ((*it).second.m_rlcStatusPduSize <= size)
        {
          size -= (*it).second.m_rlcStatusPduSize;
          (*it).second.m_rlcStatusPduSize = 0;
        }
      else
        {
          (*it).second.m_rlcStatusPduSize -= size;
          return;
        }
      // update retransmission queue  
      if ((*it).second.m_rlcRetransmissionQueueSize <= size)
        {
          size -= (*it).second.m_rlcRetransmissionQueueSize;
          (*it).second.m_rlcRetransmissionQueueSize = 0;
        }
      else
        {
          (*it).second.m_rlcRetransmissionQueueSize -= size;
          return;
        }
      // update transmission queue
      if ((*it).second.m_rlcTransmissionQueueSize <= size)
        {
          size -= (*it).second.m_rlcTransmissionQueueSize;
          (*it).second.m_rlcTransmissionQueueSize = 0;
        }
      else
        {
          (*it).second.m_rlcTransmissionQueueSize -= size;
          return;
        }
    }
  else
    {
      NS_LOG_ERROR (this << " Does not find DL RLC Buffer Report of UE " << rnti);
    }
}

void
TdMtFfMacScheduler::UpdateUlRlcBufferInfo (uint16_t rnti, uint16_t size)
{
  
  size = size - 2; // remove the minimum RLC overhead
  std::map <uint16_t,uint32_t>::iterator it = m_ceBsrRxed.find (rnti);
  if (it!=m_ceBsrRxed.end ())
    {
      if ((*it).second >= size)
        {
          (*it).second -= size;
        }
      else
        {
          (*it).second = 0;
        }
    }
  else
    {
      NS_LOG_ERROR (this << " Does not find BSR report info of UE " << rnti);
    }
  
}

void
TdMtFfMacScheduler::TransmissionModeConfigurationUpdate (uint16_t rnti, uint8_t txMode)
{
  NS_LOG_FUNCTION (this << " RNTI " << rnti << " txMode " << (uint16_t)txMode);
  FfMacCschedSapUser::CschedUeConfigUpdateIndParameters params;
  params.m_rnti = rnti;
  params.m_transmissionMode = txMode;
  m_cschedSapUser->CschedUeConfigUpdateInd (params);
}


}