fdtbfq-ff-mac-scheduler.cc

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/*
 * 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>
 * Modification: Dizhi Zhou <dizhi.zhou@gmail.com>    // modify codes related to downlink scheduler
 */
 
#include "fdtbfq-ff-mac-scheduler.h"
 
#include "lte-amc.h"
#include "lte-vendor-specific-parameters.h"
 
#include <ns3/boolean.h>
#include <ns3/integer.h>
#include <ns3/log.h>
#include <ns3/math.h>
#include <ns3/pointer.h>
#include <ns3/simulator.h>
 
#include <cfloat>
#include <set>
 
namespace ns3
{
 
NS_LOG_COMPONENT_DEFINE("FdTbfqFfMacScheduler");
 
static const int FdTbfqType0AllocationRbg[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(FdTbfqFfMacScheduler);
 
FdTbfqFfMacScheduler::FdTbfqFfMacScheduler()
    : m_cschedSapUser(nullptr),
      m_schedSapUser(nullptr),
      m_nextRntiUl(0),
      bankSize(0)
{
    m_amc = CreateObject<LteAmc>();
    m_cschedSapProvider = new MemberCschedSapProvider<FdTbfqFfMacScheduler>(this);
    m_schedSapProvider = new MemberSchedSapProvider<FdTbfqFfMacScheduler>(this);
    m_ffrSapProvider = nullptr;
    m_ffrSapUser = new MemberLteFfrSapUser<FdTbfqFfMacScheduler>(this);
}
 
FdTbfqFfMacScheduler::~FdTbfqFfMacScheduler()
{
    NS_LOG_FUNCTION(this);
}
 
void
FdTbfqFfMacScheduler::DoDispose()
{
    NS_LOG_FUNCTION(this);
    m_dlHarqProcessesDciBuffer.clear();
    m_dlHarqProcessesTimer.clear();
    m_dlHarqProcessesRlcPduListBuffer.clear();
    m_dlInfoListBuffered.clear();
    m_ulHarqCurrentProcessId.clear();
    m_ulHarqProcessesStatus.clear();
    m_ulHarqProcessesDciBuffer.clear();
    delete m_cschedSapProvider;
    delete m_schedSapProvider;
    delete m_ffrSapUser;
}
 
TypeId
FdTbfqFfMacScheduler::GetTypeId()
{
    static TypeId tid =
        TypeId("ns3::FdTbfqFfMacScheduler")
            .SetParent<FfMacScheduler>()
            .SetGroupName("Lte")
            .AddConstructor<FdTbfqFfMacScheduler>()
            .AddAttribute("CqiTimerThreshold",
                          "The number of TTIs a CQI is valid (default 1000 - 1 sec.)",
                          UintegerValue(1000),
                          MakeUintegerAccessor(&FdTbfqFfMacScheduler::m_cqiTimersThreshold),
                          MakeUintegerChecker<uint32_t>())
            .AddAttribute("DebtLimit",
                          "Flow debt limit (default -625000 bytes)",
                          IntegerValue(-625000),
                          MakeIntegerAccessor(&FdTbfqFfMacScheduler::m_debtLimit),
                          MakeIntegerChecker<int>())
            .AddAttribute("CreditLimit",
                          "Flow credit limit (default 625000 bytes)",
                          UintegerValue(625000),
                          MakeUintegerAccessor(&FdTbfqFfMacScheduler::m_creditLimit),
                          MakeUintegerChecker<uint32_t>())
            .AddAttribute("TokenPoolSize",
                          "The maximum value of flow token pool (default 1 bytes)",
                          UintegerValue(1),
                          MakeUintegerAccessor(&FdTbfqFfMacScheduler::m_tokenPoolSize),
                          MakeUintegerChecker<uint32_t>())
            .AddAttribute("CreditableThreshold",
                          "Threshold of flow credit (default 0 bytes)",
                          UintegerValue(0),
                          MakeUintegerAccessor(&FdTbfqFfMacScheduler::m_creditableThreshold),
                          MakeUintegerChecker<uint32_t>())
 
            .AddAttribute("HarqEnabled",
                          "Activate/Deactivate the HARQ [by default is active].",
                          BooleanValue(true),
                          MakeBooleanAccessor(&FdTbfqFfMacScheduler::m_harqOn),
                          MakeBooleanChecker())
            .AddAttribute("UlGrantMcs",
                          "The MCS of the UL grant, must be [0..15] (default 0)",
                          UintegerValue(0),
                          MakeUintegerAccessor(&FdTbfqFfMacScheduler::m_ulGrantMcs),
                          MakeUintegerChecker<uint8_t>());
    return tid;
}
 
void
FdTbfqFfMacScheduler::SetFfMacCschedSapUser(FfMacCschedSapUser* s)
{
    m_cschedSapUser = s;
}
 
void
FdTbfqFfMacScheduler::SetFfMacSchedSapUser(FfMacSchedSapUser* s)
{
    m_schedSapUser = s;
}
 
FfMacCschedSapProvider*
FdTbfqFfMacScheduler::GetFfMacCschedSapProvider()
{
    return m_cschedSapProvider;
}
 
FfMacSchedSapProvider*
FdTbfqFfMacScheduler::GetFfMacSchedSapProvider()
{
    return m_schedSapProvider;
}
 
void
FdTbfqFfMacScheduler::SetLteFfrSapProvider(LteFfrSapProvider* s)
{
    m_ffrSapProvider = s;
}
 
LteFfrSapUser*
FdTbfqFfMacScheduler::GetLteFfrSapUser()
{
    return m_ffrSapUser;
}
 
void
FdTbfqFfMacScheduler::DoCschedCellConfigReq(
    const FfMacCschedSapProvider::CschedCellConfigReqParameters& params)
{
    NS_LOG_FUNCTION(this);
    // Read the subset of parameters used
    m_cschedCellConfig = params;
    m_rachAllocationMap.resize(m_cschedCellConfig.m_ulBandwidth, 0);
    FfMacCschedSapUser::CschedUeConfigCnfParameters cnf;
    cnf.m_result = SUCCESS;
    m_cschedSapUser->CschedUeConfigCnf(cnf);
}
 
void
FdTbfqFfMacScheduler::DoCschedUeConfigReq(
    const 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));
        // generate HARQ buffers
        m_dlHarqCurrentProcessId.insert(std::pair<uint16_t, uint8_t>(params.m_rnti, 0));
        DlHarqProcessesStatus_t dlHarqPrcStatus;
        dlHarqPrcStatus.resize(8, 0);
        m_dlHarqProcessesStatus.insert(
            std::pair<uint16_t, DlHarqProcessesStatus_t>(params.m_rnti, dlHarqPrcStatus));
        DlHarqProcessesTimer_t dlHarqProcessesTimer;
        dlHarqProcessesTimer.resize(8, 0);
        m_dlHarqProcessesTimer.insert(
            std::pair<uint16_t, DlHarqProcessesTimer_t>(params.m_rnti, dlHarqProcessesTimer));
        DlHarqProcessesDciBuffer_t dlHarqdci;
        dlHarqdci.resize(8);
        m_dlHarqProcessesDciBuffer.insert(
            std::pair<uint16_t, DlHarqProcessesDciBuffer_t>(params.m_rnti, dlHarqdci));
        DlHarqRlcPduListBuffer_t dlHarqRlcPdu;
        dlHarqRlcPdu.resize(2);
        dlHarqRlcPdu.at(0).resize(8);
        dlHarqRlcPdu.at(1).resize(8);
        m_dlHarqProcessesRlcPduListBuffer.insert(
            std::pair<uint16_t, DlHarqRlcPduListBuffer_t>(params.m_rnti, dlHarqRlcPdu));
        m_ulHarqCurrentProcessId.insert(std::pair<uint16_t, uint8_t>(params.m_rnti, 0));
        UlHarqProcessesStatus_t ulHarqPrcStatus;
        ulHarqPrcStatus.resize(8, 0);
        m_ulHarqProcessesStatus.insert(
            std::pair<uint16_t, UlHarqProcessesStatus_t>(params.m_rnti, ulHarqPrcStatus));
        UlHarqProcessesDciBuffer_t ulHarqdci;
        ulHarqdci.resize(8);
        m_ulHarqProcessesDciBuffer.insert(
            std::pair<uint16_t, UlHarqProcessesDciBuffer_t>(params.m_rnti, ulHarqdci));
    }
    else
    {
        (*it).second = params.m_transmissionMode;
    }
}
 
void
FdTbfqFfMacScheduler::DoCschedLcConfigReq(
    const FfMacCschedSapProvider::CschedLcConfigReqParameters& params)
{
    NS_LOG_FUNCTION(this << " New LC, rnti: " << params.m_rnti);
 
    std::map<uint16_t, fdtbfqsFlowPerf_t>::iterator it;
    for (std::size_t i = 0; i < params.m_logicalChannelConfigList.size(); i++)
    {
        it = m_flowStatsDl.find(params.m_rnti);
 
        if (it == m_flowStatsDl.end())
        {
            uint64_t mbrDlInBytes =
                params.m_logicalChannelConfigList.at(i).m_eRabMaximulBitrateDl / 8; // byte/s
            uint64_t mbrUlInBytes =
                params.m_logicalChannelConfigList.at(i).m_eRabMaximulBitrateUl / 8; // byte/s
            NS_LOG_DEBUG("mbrDlInBytes: " << mbrDlInBytes << " mbrUlInBytes: " << mbrUlInBytes);
 
            fdtbfqsFlowPerf_t flowStatsDl;
            flowStatsDl.flowStart = Simulator::Now();
            flowStatsDl.packetArrivalRate = 0;
            flowStatsDl.tokenGenerationRate = mbrDlInBytes;
            flowStatsDl.tokenPoolSize = 0;
            flowStatsDl.maxTokenPoolSize = m_tokenPoolSize;
            flowStatsDl.counter = 0;
            flowStatsDl.burstCredit = m_creditLimit; // bytes
            flowStatsDl.debtLimit = m_debtLimit;     // bytes
            flowStatsDl.creditableThreshold = m_creditableThreshold;
            m_flowStatsDl.insert(
                std::pair<uint16_t, fdtbfqsFlowPerf_t>(params.m_rnti, flowStatsDl));
            fdtbfqsFlowPerf_t flowStatsUl;
            flowStatsUl.flowStart = Simulator::Now();
            flowStatsUl.packetArrivalRate = 0;
            flowStatsUl.tokenGenerationRate = mbrUlInBytes;
            flowStatsUl.tokenPoolSize = 0;
            flowStatsUl.maxTokenPoolSize = m_tokenPoolSize;
            flowStatsUl.counter = 0;
            flowStatsUl.burstCredit = m_creditLimit; // bytes
            flowStatsUl.debtLimit = m_debtLimit;     // bytes
            flowStatsUl.creditableThreshold = m_creditableThreshold;
            m_flowStatsUl.insert(
                std::pair<uint16_t, fdtbfqsFlowPerf_t>(params.m_rnti, flowStatsUl));
        }
        else
        {
            // update MBR and GBR from UeManager::SetupDataRadioBearer ()
            uint64_t mbrDlInBytes =
                params.m_logicalChannelConfigList.at(i).m_eRabMaximulBitrateDl / 8; // byte/s
            uint64_t mbrUlInBytes =
                params.m_logicalChannelConfigList.at(i).m_eRabMaximulBitrateUl / 8; // byte/s
            NS_LOG_DEBUG("mbrDlInBytes: " << mbrDlInBytes << " mbrUlInBytes: " << mbrUlInBytes);
            m_flowStatsDl[(*it).first].tokenGenerationRate = mbrDlInBytes;
            m_flowStatsUl[(*it).first].tokenGenerationRate = mbrUlInBytes;
        }
    }
}
 
void
FdTbfqFfMacScheduler::DoCschedLcReleaseReq(
    const FfMacCschedSapProvider::CschedLcReleaseReqParameters& params)
{
    NS_LOG_FUNCTION(this);
    for (std::size_t i = 0; i < params.m_logicalChannelIdentity.size(); i++)
    {
        std::map<LteFlowId_t, FfMacSchedSapProvider::SchedDlRlcBufferReqParameters>::iterator it =
            m_rlcBufferReq.begin();
        std::map<LteFlowId_t, FfMacSchedSapProvider::SchedDlRlcBufferReqParameters>::iterator temp;
        while (it != m_rlcBufferReq.end())
        {
            if (((*it).first.m_rnti == params.m_rnti) &&
                ((*it).first.m_lcId == params.m_logicalChannelIdentity.at(i)))
            {
                temp = it;
                it++;
                m_rlcBufferReq.erase(temp);
            }
            else
            {
                it++;
            }
        }
    }
}
 
void
FdTbfqFfMacScheduler::DoCschedUeReleaseReq(
    const FfMacCschedSapProvider::CschedUeReleaseReqParameters& params)
{
    NS_LOG_FUNCTION(this);
 
    m_uesTxMode.erase(params.m_rnti);
    m_dlHarqCurrentProcessId.erase(params.m_rnti);
    m_dlHarqProcessesStatus.erase(params.m_rnti);
    m_dlHarqProcessesTimer.erase(params.m_rnti);
    m_dlHarqProcessesDciBuffer.erase(params.m_rnti);
    m_dlHarqProcessesRlcPduListBuffer.erase(params.m_rnti);
    m_ulHarqCurrentProcessId.erase(params.m_rnti);
    m_ulHarqProcessesStatus.erase(params.m_rnti);
    m_ulHarqProcessesDciBuffer.erase(params.m_rnti);
    m_flowStatsDl.erase(params.m_rnti);
    m_flowStatsUl.erase(params.m_rnti);
    m_ceBsrRxed.erase(params.m_rnti);
    std::map<LteFlowId_t, FfMacSchedSapProvider::SchedDlRlcBufferReqParameters>::iterator it =
        m_rlcBufferReq.begin();
    std::map<LteFlowId_t, FfMacSchedSapProvider::SchedDlRlcBufferReqParameters>::iterator temp;
    while (it != m_rlcBufferReq.end())
    {
        if ((*it).first.m_rnti == params.m_rnti)
        {
            temp = it;
            it++;
            m_rlcBufferReq.erase(temp);
        }
        else
        {
            it++;
        }
    }
    if (m_nextRntiUl == params.m_rnti)
    {
        m_nextRntiUl = 0;
    }
}
 
void
FdTbfqFfMacScheduler::DoSchedDlRlcBufferReq(
    const 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;
    }
}
 
void
FdTbfqFfMacScheduler::DoSchedDlPagingBufferReq(
    const FfMacSchedSapProvider::SchedDlPagingBufferReqParameters& params)
{
    NS_LOG_FUNCTION(this);
    NS_FATAL_ERROR("method not implemented");
}
 
void
FdTbfqFfMacScheduler::DoSchedDlMacBufferReq(
    const FfMacSchedSapProvider::SchedDlMacBufferReqParameters& params)
{
    NS_LOG_FUNCTION(this);
    NS_FATAL_ERROR("method not implemented");
}
 
int
FdTbfqFfMacScheduler::GetRbgSize(int dlbandwidth)
{
    for (int i = 0; i < 4; i++)
    {
        if (dlbandwidth < FdTbfqType0AllocationRbg[i])
        {
            return (i + 1);
        }
    }
 
    return (-1);
}
 
unsigned int
FdTbfqFfMacScheduler::LcActivePerFlow(uint16_t rnti)
{
    std::map<LteFlowId_t, FfMacSchedSapProvider::SchedDlRlcBufferReqParameters>::iterator it;
    unsigned 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);
}
 
bool
FdTbfqFfMacScheduler::HarqProcessAvailability(uint16_t rnti)
{
    NS_LOG_FUNCTION(this << rnti);
 
    std::map<uint16_t, uint8_t>::iterator it = m_dlHarqCurrentProcessId.find(rnti);
    if (it == m_dlHarqCurrentProcessId.end())
    {
        NS_FATAL_ERROR("No Process Id found for this RNTI " << rnti);
    }
    std::map<uint16_t, DlHarqProcessesStatus_t>::iterator itStat =
        m_dlHarqProcessesStatus.find(rnti);
    if (itStat == m_dlHarqProcessesStatus.end())
    {
        NS_FATAL_ERROR("No Process Id Statusfound for this RNTI " << rnti);
    }
    uint8_t i = (*it).second;
    do
    {
        i = (i + 1) % HARQ_PROC_NUM;
    } while (((*itStat).second.at(i) != 0) && (i != (*it).second));
 
    return (*itStat).second.at(i) == 0;
}
 
uint8_t
FdTbfqFfMacScheduler::UpdateHarqProcessId(uint16_t rnti)
{
    NS_LOG_FUNCTION(this << rnti);
 
    if (!m_harqOn)
    {
        return (0);
    }
 
    std::map<uint16_t, uint8_t>::iterator it = m_dlHarqCurrentProcessId.find(rnti);
    if (it == m_dlHarqCurrentProcessId.end())
    {
        NS_FATAL_ERROR("No Process Id found for this RNTI " << rnti);
    }
    std::map<uint16_t, DlHarqProcessesStatus_t>::iterator itStat =
        m_dlHarqProcessesStatus.find(rnti);
    if (itStat == m_dlHarqProcessesStatus.end())
    {
        NS_FATAL_ERROR("No Process Id Statusfound for this RNTI " << rnti);
    }
    uint8_t i = (*it).second;
    do
    {
        i = (i + 1) % HARQ_PROC_NUM;
    } while (((*itStat).second.at(i) != 0) && (i != (*it).second));
    if ((*itStat).second.at(i) == 0)
    {
        (*it).second = i;
        (*itStat).second.at(i) = 1;
    }
    else
    {
        NS_FATAL_ERROR("No HARQ process available for RNTI "
                       << rnti << " check before update with HarqProcessAvailability");
    }
 
    return ((*it).second);
}
 
void
FdTbfqFfMacScheduler::RefreshHarqProcesses()
{
    NS_LOG_FUNCTION(this);
 
    std::map<uint16_t, DlHarqProcessesTimer_t>::iterator itTimers;
    for (itTimers = m_dlHarqProcessesTimer.begin(); itTimers != m_dlHarqProcessesTimer.end();
         itTimers++)
    {
        for (uint16_t i = 0; i < HARQ_PROC_NUM; i++)
        {
            if ((*itTimers).second.at(i) == HARQ_DL_TIMEOUT)
            {
                // reset HARQ process
 
                NS_LOG_DEBUG(this << " Reset HARQ proc " << i << " for RNTI " << (*itTimers).first);
                std::map<uint16_t, DlHarqProcessesStatus_t>::iterator itStat =
                    m_dlHarqProcessesStatus.find((*itTimers).first);
                if (itStat == m_dlHarqProcessesStatus.end())
                {
                    NS_FATAL_ERROR("No Process Id Status found for this RNTI "
                                   << (*itTimers).first);
                }
                (*itStat).second.at(i) = 0;
                (*itTimers).second.at(i) = 0;
            }
            else
            {
                (*itTimers).second.at(i)++;
            }
        }
    }
}
 
void
FdTbfqFfMacScheduler::DoSchedDlTriggerReq(
    const 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; // RBs map per RNTI
    std::vector<bool> rbgMap;                                // global RBGs map
    uint16_t rbgAllocatedNum = 0;
    std::set<uint16_t> rntiAllocated;
    rbgMap.resize(m_cschedCellConfig.m_dlBandwidth / rbgSize, false);
 
    rbgMap = m_ffrSapProvider->GetAvailableDlRbg();
    for (std::vector<bool>::iterator it = rbgMap.begin(); it != rbgMap.end(); it++)
    {
        if (*it)
        {
            rbgAllocatedNum++;
        }
    }
 
    FfMacSchedSapUser::SchedDlConfigIndParameters ret;
 
    //   update UL HARQ proc id
    std::map<uint16_t, uint8_t>::iterator itProcId;
    for (itProcId = m_ulHarqCurrentProcessId.begin(); itProcId != m_ulHarqCurrentProcessId.end();
         itProcId++)
    {
        (*itProcId).second = ((*itProcId).second + 1) % HARQ_PROC_NUM;
    }
 
    // RACH Allocation
    std::vector<bool> ulRbMap;
    ulRbMap.resize(m_cschedCellConfig.m_ulBandwidth, false);
    ulRbMap = m_ffrSapProvider->GetAvailableUlRbg();
    uint8_t maxContinuousUlBandwidth = 0;
    uint8_t tmpMinBandwidth = 0;
    uint16_t ffrRbStartOffset = 0;
    uint16_t tmpFfrRbStartOffset = 0;
    uint16_t index = 0;
 
    for (std::vector<bool>::iterator it = ulRbMap.begin(); it != ulRbMap.end(); it++)
    {
        if (*it)
        {
            if (tmpMinBandwidth > maxContinuousUlBandwidth)
            {
                maxContinuousUlBandwidth = tmpMinBandwidth;
                ffrRbStartOffset = tmpFfrRbStartOffset;
            }
            tmpMinBandwidth = 0;
        }
        else
        {
            if (tmpMinBandwidth == 0)
            {
                tmpFfrRbStartOffset = index;
            }
            tmpMinBandwidth++;
        }
        index++;
    }
 
    if (tmpMinBandwidth > maxContinuousUlBandwidth)
    {
        maxContinuousUlBandwidth = tmpMinBandwidth;
        ffrRbStartOffset = tmpFfrRbStartOffset;
    }
 
    m_rachAllocationMap.resize(m_cschedCellConfig.m_ulBandwidth, 0);
    uint16_t rbStart = 0;
    rbStart = ffrRbStartOffset;
    std::vector<RachListElement_s>::iterator itRach;
    for (itRach = m_rachList.begin(); itRach != m_rachList.end(); itRach++)
    {
        NS_ASSERT_MSG(m_amc->GetUlTbSizeFromMcs(m_ulGrantMcs, m_cschedCellConfig.m_ulBandwidth) >
                          (*itRach).m_estimatedSize,
                      " Default UL Grant MCS does not allow to send RACH messages");
        BuildRarListElement_s newRar;
        newRar.m_rnti = (*itRach).m_rnti;
        // DL-RACH Allocation
        // Ideal: no needs of configuring m_dci
        // UL-RACH Allocation
        newRar.m_grant.m_rnti = newRar.m_rnti;
        newRar.m_grant.m_mcs = m_ulGrantMcs;
        uint16_t rbLen = 1;
        uint16_t tbSizeBits = 0;
        // find lowest TB size that fits UL grant estimated size
        while ((tbSizeBits < (*itRach).m_estimatedSize) &&
               (rbStart + rbLen < (ffrRbStartOffset + maxContinuousUlBandwidth)))
        {
            rbLen++;
            tbSizeBits = m_amc->GetUlTbSizeFromMcs(m_ulGrantMcs, rbLen);
        }
        if (tbSizeBits < (*itRach).m_estimatedSize)
        {
            // no more allocation space: finish allocation
            break;
        }
        newRar.m_grant.m_rbStart = rbStart;
        newRar.m_grant.m_rbLen = rbLen;
        newRar.m_grant.m_tbSize = tbSizeBits / 8;
        newRar.m_grant.m_hopping = false;
        newRar.m_grant.m_tpc = 0;
        newRar.m_grant.m_cqiRequest = false;
        newRar.m_grant.m_ulDelay = false;
        NS_LOG_INFO(this << " UL grant allocated to RNTI " << (*itRach).m_rnti << " rbStart "
                         << rbStart << " rbLen " << rbLen << " MCS " << (uint16_t)m_ulGrantMcs
                         << " tbSize " << newRar.m_grant.m_tbSize);
        for (uint16_t i = rbStart; i < rbStart + rbLen; i++)
        {
            m_rachAllocationMap.at(i) = (*itRach).m_rnti;
        }
 
        if (m_harqOn)
        {
            // generate UL-DCI for HARQ retransmissions
            UlDciListElement_s uldci;
            uldci.m_rnti = newRar.m_rnti;
            uldci.m_rbLen = rbLen;
            uldci.m_rbStart = rbStart;
            uldci.m_mcs = m_ulGrantMcs;
            uldci.m_tbSize = tbSizeBits / 8;
            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
 
            uint8_t harqId = 0;
            std::map<uint16_t, uint8_t>::iterator itProcId;
            itProcId = m_ulHarqCurrentProcessId.find(uldci.m_rnti);
            if (itProcId == m_ulHarqCurrentProcessId.end())
            {
                NS_FATAL_ERROR("No info find in HARQ buffer for UE " << uldci.m_rnti);
            }
            harqId = (*itProcId).second;
            std::map<uint16_t, UlHarqProcessesDciBuffer_t>::iterator itDci =
                m_ulHarqProcessesDciBuffer.find(uldci.m_rnti);
            if (itDci == m_ulHarqProcessesDciBuffer.end())
            {
                NS_FATAL_ERROR("Unable to find RNTI entry in UL DCI HARQ buffer for RNTI "
                               << uldci.m_rnti);
            }
            (*itDci).second.at(harqId) = uldci;
        }
 
        rbStart = rbStart + rbLen;
        ret.m_buildRarList.push_back(newRar);
    }
    m_rachList.clear();
 
    // Process DL HARQ feedback
    RefreshHarqProcesses();
    // retrieve past HARQ retx buffered
    if (!m_dlInfoListBuffered.empty())
    {
        if (!params.m_dlInfoList.empty())
        {
            NS_LOG_INFO(this << " Received DL-HARQ feedback");
            m_dlInfoListBuffered.insert(m_dlInfoListBuffered.end(),
                                        params.m_dlInfoList.begin(),
                                        params.m_dlInfoList.end());
        }
    }
    else
    {
        if (!params.m_dlInfoList.empty())
        {
            m_dlInfoListBuffered = params.m_dlInfoList;
        }
    }
    if (!m_harqOn)
    {
        // Ignore HARQ feedback
        m_dlInfoListBuffered.clear();
    }
    std::vector<DlInfoListElement_s> dlInfoListUntxed;
    for (std::size_t i = 0; i < m_dlInfoListBuffered.size(); i++)
    {
        std::set<uint16_t>::iterator itRnti = rntiAllocated.find(m_dlInfoListBuffered.at(i).m_rnti);
        if (itRnti != rntiAllocated.end())
        {
            // RNTI already allocated for retx
            continue;
        }
        auto nLayers = m_dlInfoListBuffered.at(i).m_harqStatus.size();
        std::vector<bool> retx;
        NS_LOG_INFO(this << " Processing DLHARQ feedback");
        if (nLayers == 1)
        {
            retx.push_back(m_dlInfoListBuffered.at(i).m_harqStatus.at(0) ==
                           DlInfoListElement_s::NACK);
            retx.push_back(false);
        }
        else
        {
            retx.push_back(m_dlInfoListBuffered.at(i).m_harqStatus.at(0) ==
                           DlInfoListElement_s::NACK);
            retx.push_back(m_dlInfoListBuffered.at(i).m_harqStatus.at(1) ==
                           DlInfoListElement_s::NACK);
        }
        if (retx.at(0) || retx.at(1))
        {
            // retrieve HARQ process information
            uint16_t rnti = m_dlInfoListBuffered.at(i).m_rnti;
            uint8_t harqId = m_dlInfoListBuffered.at(i).m_harqProcessId;
            NS_LOG_INFO(this << " HARQ retx RNTI " << rnti << " harqId " << (uint16_t)harqId);
            std::map<uint16_t, DlHarqProcessesDciBuffer_t>::iterator itHarq =
                m_dlHarqProcessesDciBuffer.find(rnti);
            if (itHarq == m_dlHarqProcessesDciBuffer.end())
            {
                NS_FATAL_ERROR("No info find in HARQ buffer for UE " << rnti);
            }
 
            DlDciListElement_s dci = (*itHarq).second.at(harqId);
            int rv = 0;
            if (dci.m_rv.size() == 1)
            {
                rv = dci.m_rv.at(0);
            }
            else
            {
                rv = (dci.m_rv.at(0) > dci.m_rv.at(1) ? dci.m_rv.at(0) : dci.m_rv.at(1));
            }
 
            if (rv == 3)
            {
                // maximum number of retx reached -> drop process
                NS_LOG_INFO("Maximum number of retransmissions reached -> drop process");
                std::map<uint16_t, DlHarqProcessesStatus_t>::iterator it =
                    m_dlHarqProcessesStatus.find(rnti);
                if (it == m_dlHarqProcessesStatus.end())
                {
                    NS_LOG_ERROR("No info find in HARQ buffer for UE (might change eNB) "
                                 << m_dlInfoListBuffered.at(i).m_rnti);
                }
                (*it).second.at(harqId) = 0;
                std::map<uint16_t, DlHarqRlcPduListBuffer_t>::iterator itRlcPdu =
                    m_dlHarqProcessesRlcPduListBuffer.find(rnti);
                if (itRlcPdu == m_dlHarqProcessesRlcPduListBuffer.end())
                {
                    NS_FATAL_ERROR("Unable to find RlcPdcList in HARQ buffer for RNTI "
                                   << m_dlInfoListBuffered.at(i).m_rnti);
                }
                for (std::size_t k = 0; k < (*itRlcPdu).second.size(); k++)
                {
                    (*itRlcPdu).second.at(k).at(harqId).clear();
                }
                continue;
            }
            // check the feasibility of retransmitting on the same RBGs
            // translate the DCI to Spectrum framework
            std::vector<int> dciRbg;
            uint32_t mask = 0x1;
            NS_LOG_INFO("Original RBGs " << dci.m_rbBitmap << " rnti " << dci.m_rnti);
            for (int j = 0; j < 32; j++)
            {
                if (((dci.m_rbBitmap & mask) >> j) == 1)
                {
                    dciRbg.push_back(j);
                    NS_LOG_INFO("\t" << j);
                }
                mask = (mask << 1);
            }
            bool free = true;
            for (std::size_t j = 0; j < dciRbg.size(); j++)
            {
                if (rbgMap.at(dciRbg.at(j)))
                {
                    free = false;
                    break;
                }
            }
            if (free)
            {
                // use the same RBGs for the retx
                // reserve RBGs
                for (std::size_t j = 0; j < dciRbg.size(); j++)
                {
                    rbgMap.at(dciRbg.at(j)) = true;
                    NS_LOG_INFO("RBG " << dciRbg.at(j) << " assigned");
                    rbgAllocatedNum++;
                }
 
                NS_LOG_INFO(this << " Send retx in the same RBGs");
            }
            else
            {
                // find RBGs for sending HARQ retx
                uint8_t j = 0;
                uint8_t rbgId = (dciRbg.at(dciRbg.size() - 1) + 1) % rbgNum;
                uint8_t startRbg = dciRbg.at(dciRbg.size() - 1);
                std::vector<bool> rbgMapCopy = rbgMap;
                while ((j < dciRbg.size()) && (startRbg != rbgId))
                {
                    if (!rbgMapCopy.at(rbgId))
                    {
                        rbgMapCopy.at(rbgId) = true;
                        dciRbg.at(j) = rbgId;
                        j++;
                    }
                    rbgId = (rbgId + 1) % rbgNum;
                }
                if (j == dciRbg.size())
                {
                    // find new RBGs -> update DCI map
                    uint32_t rbgMask = 0;
                    for (std::size_t k = 0; k < dciRbg.size(); k++)
                    {
                        rbgMask = rbgMask + (0x1 << dciRbg.at(k));
                        rbgAllocatedNum++;
                    }
                    dci.m_rbBitmap = rbgMask;
                    rbgMap = rbgMapCopy;
                    NS_LOG_INFO(this << " Move retx in RBGs " << dciRbg.size());
                }
                else
                {
                    // HARQ retx cannot be performed on this TTI -> store it
                    dlInfoListUntxed.push_back(m_dlInfoListBuffered.at(i));
                    NS_LOG_INFO(this << " No resource for this retx -> buffer it");
                }
            }
            // retrieve RLC PDU list for retx TBsize and update DCI
            BuildDataListElement_s newEl;
            std::map<uint16_t, DlHarqRlcPduListBuffer_t>::iterator itRlcPdu =
                m_dlHarqProcessesRlcPduListBuffer.find(rnti);
            if (itRlcPdu == m_dlHarqProcessesRlcPduListBuffer.end())
            {
                NS_FATAL_ERROR("Unable to find RlcPdcList in HARQ buffer for RNTI " << rnti);
            }
            for (std::size_t j = 0; j < nLayers; j++)
            {
                if (retx.at(j))
                {
                    if (j >= dci.m_ndi.size())
                    {
                        // for avoiding errors in MIMO transient phases
                        dci.m_ndi.push_back(0);
                        dci.m_rv.push_back(0);
                        dci.m_mcs.push_back(0);
                        dci.m_tbsSize.push_back(0);
                        NS_LOG_INFO(this << " layer " << (uint16_t)j
                                         << " no txed (MIMO transition)");
                    }
                    else
                    {
                        dci.m_ndi.at(j) = 0;
                        dci.m_rv.at(j)++;
                        (*itHarq).second.at(harqId).m_rv.at(j)++;
                        NS_LOG_INFO(this << " layer " << (uint16_t)j << " RV "
                                         << (uint16_t)dci.m_rv.at(j));
                    }
                }
                else
                {
                    // empty TB of layer j
                    dci.m_ndi.at(j) = 0;
                    dci.m_rv.at(j) = 0;
                    dci.m_mcs.at(j) = 0;
                    dci.m_tbsSize.at(j) = 0;
                    NS_LOG_INFO(this << " layer " << (uint16_t)j << " no retx");
                }
            }
            for (std::size_t k = 0; k < (*itRlcPdu).second.at(0).at(dci.m_harqProcess).size(); k++)
            {
                std::vector<RlcPduListElement_s> rlcPduListPerLc;
                for (std::size_t j = 0; j < nLayers; j++)
                {
                    if (retx.at(j))
                    {
                        if (j < dci.m_ndi.size())
                        {
                            NS_LOG_INFO(" layer " << (uint16_t)j << " tb size "
                                                  << dci.m_tbsSize.at(j));
                            rlcPduListPerLc.push_back(
                                (*itRlcPdu).second.at(j).at(dci.m_harqProcess).at(k));
                        }
                    }
                    else
                    { // if no retx needed on layer j, push an RlcPduListElement_s object with
                      // m_size=0 to keep the size of rlcPduListPerLc vector = 2 in case of MIMO
                        NS_LOG_INFO(" layer " << (uint16_t)j << " tb size " << dci.m_tbsSize.at(j));
                        RlcPduListElement_s emptyElement;
                        emptyElement.m_logicalChannelIdentity = (*itRlcPdu)
                                                                    .second.at(j)
                                                                    .at(dci.m_harqProcess)
                                                                    .at(k)
                                                                    .m_logicalChannelIdentity;
                        emptyElement.m_size = 0;
                        rlcPduListPerLc.push_back(emptyElement);
                    }
                }
 
                if (!rlcPduListPerLc.empty())
                {
                    newEl.m_rlcPduList.push_back(rlcPduListPerLc);
                }
            }
            newEl.m_rnti = rnti;
            newEl.m_dci = dci;
            (*itHarq).second.at(harqId).m_rv = dci.m_rv;
            // refresh timer
            std::map<uint16_t, DlHarqProcessesTimer_t>::iterator itHarqTimer =
                m_dlHarqProcessesTimer.find(rnti);
            if (itHarqTimer == m_dlHarqProcessesTimer.end())
            {
                NS_FATAL_ERROR("Unable to find HARQ timer for RNTI " << (uint16_t)rnti);
            }
            (*itHarqTimer).second.at(harqId) = 0;
            ret.m_buildDataList.push_back(newEl);
            rntiAllocated.insert(rnti);
        }
        else
        {
            // update HARQ process status
            NS_LOG_INFO(this << " HARQ received ACK for UE " << m_dlInfoListBuffered.at(i).m_rnti);
            std::map<uint16_t, DlHarqProcessesStatus_t>::iterator it =
                m_dlHarqProcessesStatus.find(m_dlInfoListBuffered.at(i).m_rnti);
            if (it == m_dlHarqProcessesStatus.end())
            {
                NS_FATAL_ERROR("No info find in HARQ buffer for UE "
                               << m_dlInfoListBuffered.at(i).m_rnti);
            }
            (*it).second.at(m_dlInfoListBuffered.at(i).m_harqProcessId) = 0;
            std::map<uint16_t, DlHarqRlcPduListBuffer_t>::iterator itRlcPdu =
                m_dlHarqProcessesRlcPduListBuffer.find(m_dlInfoListBuffered.at(i).m_rnti);
            if (itRlcPdu == m_dlHarqProcessesRlcPduListBuffer.end())
            {
                NS_FATAL_ERROR("Unable to find RlcPdcList in HARQ buffer for RNTI "
                               << m_dlInfoListBuffered.at(i).m_rnti);
            }
            for (std::size_t k = 0; k < (*itRlcPdu).second.size(); k++)
            {
                (*itRlcPdu).second.at(k).at(m_dlInfoListBuffered.at(i).m_harqProcessId).clear();
            }
        }
    }
    m_dlInfoListBuffered.clear();
    m_dlInfoListBuffered = dlInfoListUntxed;
 
    if (rbgAllocatedNum == rbgNum)
    {
        // all the RBGs are already allocated -> exit
        if (!ret.m_buildDataList.empty() || !ret.m_buildRarList.empty())
        {
            m_schedSapUser->SchedDlConfigInd(ret);
        }
        return;
    }
 
    // update token pool, counter and bank size
    std::map<uint16_t, fdtbfqsFlowPerf_t>::iterator itStats;
    for (itStats = m_flowStatsDl.begin(); itStats != m_flowStatsDl.end(); itStats++)
    {
        if ((*itStats).second.tokenGenerationRate / 1000 + (*itStats).second.tokenPoolSize >
            (*itStats).second.maxTokenPoolSize)
        {
            (*itStats).second.counter +=
                (*itStats).second.tokenGenerationRate / 1000 -
                ((*itStats).second.maxTokenPoolSize - (*itStats).second.tokenPoolSize);
            (*itStats).second.tokenPoolSize = (*itStats).second.maxTokenPoolSize;
            bankSize += (*itStats).second.tokenGenerationRate / 1000 -
                        ((*itStats).second.maxTokenPoolSize - (*itStats).second.tokenPoolSize);
        }
        else
        {
            (*itStats).second.tokenPoolSize += (*itStats).second.tokenGenerationRate / 1000;
        }
    }
 
    std::set<uint16_t> allocatedRnti; // store UEs which are already assigned RBGs
    std::set<uint8_t> allocatedRbg;   // store RBGs which are already allocated to UE
 
    int totalRbg = 0;
    while (totalRbg < rbgNum)
    {
        // select UE with largest metric
        std::map<uint16_t, fdtbfqsFlowPerf_t>::iterator it;
        std::map<uint16_t, fdtbfqsFlowPerf_t>::iterator itMax = m_flowStatsDl.end();
        double metricMax = 0.0;
        bool firstRnti = true;
        for (it = m_flowStatsDl.begin(); it != m_flowStatsDl.end(); it++)
        {
            std::set<uint16_t>::iterator itRnti = rntiAllocated.find((*it).first);
            if ((itRnti != rntiAllocated.end()) || (!HarqProcessAvailability((*it).first)))
            {
                // UE already allocated for HARQ or without HARQ process available -> drop it
                if (itRnti != rntiAllocated.end())
                {
                    NS_LOG_DEBUG(this << " RNTI discarded for HARQ tx" << (uint16_t)(*it).first);
                }
                if (!HarqProcessAvailability((*it).first))
                {
                    NS_LOG_DEBUG(this << " RNTI discarded for HARQ id" << (uint16_t)(*it).first);
                }
                continue;
            }
            // check first the channel conditions for this UE, if CQI!=0
            std::map<uint16_t, SbMeasResult_s>::iterator itCqi;
            itCqi = m_a30CqiRxed.find((*it).first);
            std::map<uint16_t, uint8_t>::iterator itTxMode;
            itTxMode = m_uesTxMode.find((*it).first);
            if (itTxMode == m_uesTxMode.end())
            {
                NS_FATAL_ERROR("No Transmission Mode info on user " << (*it).first);
            }
            auto nLayer = TransmissionModesLayers::TxMode2LayerNum((*itTxMode).second);
 
            uint8_t cqiSum = 0;
            for (int k = 0; k < rbgNum; k++)
            {
                for (uint8_t j = 0; j < nLayer; j++)
                {
                    if (itCqi == m_a30CqiRxed.end())
                    {
                        cqiSum += 1; // no info on this user -> lowest MCS
                    }
                    else
                    {
                        cqiSum += (*itCqi).second.m_higherLayerSelected.at(k).m_sbCqi.at(j);
                    }
                }
            }
 
            if (cqiSum == 0)
            {
                NS_LOG_INFO("Skip this flow, CQI==0, rnti:" << (*it).first);
                continue;
            }
 
            if (LcActivePerFlow((*it).first) == 0)
            {
                continue;
            }
 
            std::set<uint16_t>::iterator rnti;
            rnti = allocatedRnti.find((*it).first);
            if (rnti != allocatedRnti.end()) //  already allocated RBGs to this UE
            {
                continue;
            }
 
            double metric =
                (((double)(*it).second.counter) / ((double)(*it).second.tokenGenerationRate));
 
            if (firstRnti)
            {
                metricMax = metric;
                itMax = it;
                firstRnti = false;
                continue;
            }
            if (metric > metricMax)
            {
                metricMax = metric;
                itMax = it;
            }
        } // end for m_flowStatsDl
 
        if (itMax == m_flowStatsDl.end())
        {
            // all UEs are allocated RBG or all UEs already allocated for HARQ or without HARQ
            // process available
            break;
        }
 
        // mark this UE as "allocated"
        allocatedRnti.insert((*itMax).first);
 
        // calculate the maximum number of byte that the scheduler can assigned to this UE
        uint32_t budget = 0;
        if (bankSize > 0)
        {
            budget = (*itMax).second.counter - (*itMax).second.debtLimit;
            if (budget > (*itMax).second.burstCredit)
            {
                budget = (*itMax).second.burstCredit;
            }
            if (budget > bankSize)
            {
                budget = bankSize;
            }
        }
        budget = budget + (*itMax).second.tokenPoolSize;
 
        // calculate how much bytes this UE actually need
        if (budget == 0)
        {
            // there are no tokens for this UE
            continue;
        }
        else
        {
            // calculate rlc buffer size
            uint32_t rlcBufSize = 0;
            uint8_t lcid = 0;
            std::map<LteFlowId_t, FfMacSchedSapProvider::SchedDlRlcBufferReqParameters>::iterator
                itRlcBuf;
            for (itRlcBuf = m_rlcBufferReq.begin(); itRlcBuf != m_rlcBufferReq.end(); itRlcBuf++)
            {
                if ((*itRlcBuf).first.m_rnti == (*itMax).first)
                {
                    lcid = (*itRlcBuf).first.m_lcId;
                }
            }
            LteFlowId_t flow((*itMax).first, lcid);
            itRlcBuf = m_rlcBufferReq.find(flow);
            if (itRlcBuf != m_rlcBufferReq.end())
            {
                rlcBufSize = (*itRlcBuf).second.m_rlcTransmissionQueueSize +
                             (*itRlcBuf).second.m_rlcRetransmissionQueueSize +
                             (*itRlcBuf).second.m_rlcStatusPduSize;
            }
            if (budget > rlcBufSize)
            {
                budget = rlcBufSize;
                NS_LOG_DEBUG("budget > rlcBufSize. budget: " << budget
                                                             << " RLC buffer size: " << rlcBufSize);
            }
        }
 
        // assign RBGs to this UE
        uint32_t bytesTxed = 0;
        uint32_t bytesTxedTmp = 0;
        int rbgIndex = 0;
        while (bytesTxed <= budget)
        {
            totalRbg++;
 
            std::map<uint16_t, SbMeasResult_s>::iterator itCqi;
            itCqi = m_a30CqiRxed.find((*itMax).first);
            std::map<uint16_t, uint8_t>::iterator itTxMode;
            itTxMode = m_uesTxMode.find((*itMax).first);
            if (itTxMode == m_uesTxMode.end())
            {
                NS_FATAL_ERROR("No Transmission Mode info on user " << (*it).first);
            }
            auto nLayer = TransmissionModesLayers::TxMode2LayerNum((*itTxMode).second);
 
            // find RBG with largest achievableRate
            double achievableRateMax = 0.0;
            rbgIndex = rbgNum;
            for (int k = 0; k < rbgNum; k++)
            {
                std::set<uint8_t>::iterator rbg;
                rbg = allocatedRbg.find(k);
                if (rbg != allocatedRbg.end()) // RBGs are already allocated to this UE
                {
                    continue;
                }
 
                if (rbgMap.at(k)) // this RBG is allocated in RACH procedure
                {
                    continue;
                }
 
                if (!m_ffrSapProvider->IsDlRbgAvailableForUe(k, (*itMax).first))
                {
                    continue;
                }
 
                std::vector<uint8_t> sbCqi;
                if (itCqi == m_a30CqiRxed.end())
                {
                    for (uint8_t k = 0; k < nLayer; k++)
                    {
                        sbCqi.push_back(1); // start with lowest value
                    }
                }
                else
                {
                    sbCqi = (*itCqi).second.m_higherLayerSelected.at(k).m_sbCqi;
                }
                uint8_t cqi1 = sbCqi.at(0);
                uint8_t cqi2 = 0;
                if (sbCqi.size() > 1)
                {
                    cqi2 = sbCqi.at(1);
                }
 
                if ((cqi1 > 0) ||
                    (cqi2 > 0)) // CQI == 0 means "out of range" (see table 7.2.3-1 of 36.213)
                {
                    if (LcActivePerFlow((*itMax).first) > 0)
                    {
                        // this UE has data to transmit
                        double achievableRate = 0.0;
                        for (uint8_t j = 0; j < nLayer; j++)
                        {
                            uint8_t mcs = 0;
                            if (sbCqi.size() > j)
                            {
                                mcs = m_amc->GetMcsFromCqi(sbCqi.at(j));
                            }
                            else
                            {
                                // no info on this subband -> worst MCS
                                mcs = 0;
                            }
                            achievableRate += ((m_amc->GetDlTbSizeFromMcs(mcs, rbgSize) / 8) /
                                               0.001); // = TB size / TTI
                        }
 
                        if (achievableRate > achievableRateMax)
                        {
                            achievableRateMax = achievableRate;
                            rbgIndex = k;
                        }
                    } // end of LcActivePerFlow
                }     // end of cqi
            }         // end of for rbgNum
 
            if (rbgIndex == rbgNum) // impossible
            {
                // all RBGs are already assigned
                totalRbg = rbgNum;
                break;
            }
            else
            {
                // mark this UE as "allocated"
                allocatedRbg.insert(rbgIndex);
            }
 
            // assign this RBG to UE
            std::map<uint16_t, std::vector<uint16_t>>::iterator itMap;
            itMap = allocationMap.find((*itMax).first);
            uint16_t RbgPerRnti;
            if (itMap == allocationMap.end())
            {
                // insert new element
                std::vector<uint16_t> tempMap;
                tempMap.push_back(rbgIndex);
                allocationMap.insert(
                    std::pair<uint16_t, std::vector<uint16_t>>((*itMax).first, tempMap));
                itMap = allocationMap.find(
                    (*itMax).first); // point itMap to the first RBGs assigned to this UE
            }
            else
            {
                (*itMap).second.push_back(rbgIndex);
            }
            rbgMap.at(rbgIndex) = true; // Mark this RBG as allocated
 
            RbgPerRnti = (*itMap).second.size();
 
            // calculate tb size
            std::vector<uint8_t> worstCqi(2, 15);
            if (itCqi != m_a30CqiRxed.end())
            {
                for (std::size_t k = 0; k < (*itMap).second.size(); k++)
                {
                    if ((*itCqi).second.m_higherLayerSelected.size() > (*itMap).second.at(k))
                    {
                        for (uint8_t j = 0; j < nLayer; j++)
                        {
                            if ((*itCqi)
                                    .second.m_higherLayerSelected.at((*itMap).second.at(k))
                                    .m_sbCqi.size() > j)
                            {
                                if (((*itCqi)
                                         .second.m_higherLayerSelected.at((*itMap).second.at(k))
                                         .m_sbCqi.at(j)) < worstCqi.at(j))
                                {
                                    worstCqi.at(j) =
                                        ((*itCqi)
                                             .second.m_higherLayerSelected.at((*itMap).second.at(k))
                                             .m_sbCqi.at(j));
                                }
                            }
                            else
                            {
                                // no CQI for this layer of this suband -> worst one
                                worstCqi.at(j) = 1;
                            }
                        }
                    }
                    else
                    {
                        for (uint8_t j = 0; j < nLayer; j++)
                        {
                            worstCqi.at(j) =
                                1; // try with lowest MCS in RBG with no info on channel
                        }
                    }
                }
            }
            else
            {
                for (uint8_t j = 0; j < nLayer; j++)
                {
                    worstCqi.at(j) = 1; // try with lowest MCS in RBG with no info on channel
                }
            }
 
            bytesTxedTmp = bytesTxed;
            bytesTxed = 0;
            for (uint8_t j = 0; j < nLayer; j++)
            {
                int tbSize = (m_amc->GetDlTbSizeFromMcs(m_amc->GetMcsFromCqi(worstCqi.at(j)),
                                                        RbgPerRnti * rbgSize) /
                              8); // (size of TB in bytes according to table 7.1.7.2.1-1 of 36.213)
                bytesTxed += tbSize;
            }
 
        } // end of while()
 
        // remove and unmark last RBG assigned to UE
        if (bytesTxed > budget)
        {
            NS_LOG_DEBUG("budget: " << budget << " bytesTxed: " << bytesTxed << " at "
                                    << Simulator::Now().As(Time::MS));
            std::map<uint16_t, std::vector<uint16_t>>::iterator itMap;
            itMap = allocationMap.find((*itMax).first);
            (*itMap).second.pop_back();
            allocatedRbg.erase(rbgIndex);
            bytesTxed = bytesTxedTmp; // recovery bytesTxed
            totalRbg--;
            rbgMap.at(rbgIndex) = false; // unmark this RBG
            // If all the RBGs are removed from the allocation
            // of this RNTI, we remove the UE from the allocation map
            if ((*itMap).second.empty())
            {
                itMap = allocationMap.erase(itMap);
            }
        }
 
        // only update the UE stats if it exists in the allocation map
        if (allocationMap.find((*itMax).first) != allocationMap.end())
        {
            // update UE stats
            if (bytesTxed <= (*itMax).second.tokenPoolSize)
            {
                (*itMax).second.tokenPoolSize -= bytesTxed;
            }
            else
            {
                (*itMax).second.counter =
                    (*itMax).second.counter - (bytesTxed - (*itMax).second.tokenPoolSize);
                (*itMax).second.tokenPoolSize = 0;
                if (bankSize <= (bytesTxed - (*itMax).second.tokenPoolSize))
                {
                    bankSize = 0;
                }
                else
                {
                    bankSize = bankSize - (bytesTxed - (*itMax).second.tokenPoolSize);
                }
            }
        }
    } // end of RBGs
 
    // generate the transmission opportunities by grouping the RBGs of the same RNTI and
    // creating the correspondent DCIs
    std::map<uint16_t, std::vector<uint16_t>>::iterator itMap = allocationMap.begin();
    while (itMap != allocationMap.end())
    {
        NS_LOG_DEBUG("Preparing DCI for RNTI " << (*itMap).first);
        // create new BuildDataListElement_s for this LC
        BuildDataListElement_s newEl;
        newEl.m_rnti = (*itMap).first;
        // create the DlDciListElement_s
        DlDciListElement_s newDci;
        newDci.m_rnti = (*itMap).first;
        newDci.m_harqProcess = UpdateHarqProcessId((*itMap).first);
 
        uint16_t lcActives = LcActivePerFlow((*itMap).first);
        NS_LOG_INFO(this << "Allocate user " << newEl.m_rnti << " rbg " << lcActives);
        if (lcActives == 0)
        {
            // Set to max value, to avoid divide by 0 below
            lcActives = (uint16_t)65535; // UINT16_MAX;
        }
        uint16_t RgbPerRnti = (*itMap).second.size();
        std::map<uint16_t, SbMeasResult_s>::iterator itCqi;
        itCqi = m_a30CqiRxed.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);
        }
        auto nLayer = TransmissionModesLayers::TxMode2LayerNum((*itTxMode).second);
        std::vector<uint8_t> worstCqi(2, 15);
        if (itCqi != m_a30CqiRxed.end())
        {
            for (std::size_t k = 0; k < (*itMap).second.size(); k++)
            {
                if ((*itCqi).second.m_higherLayerSelected.size() > (*itMap).second.at(k))
                {
                    NS_LOG_INFO(this << " RBG " << (*itMap).second.at(k) << " CQI "
                                     << (uint16_t)((*itCqi)
                                                       .second.m_higherLayerSelected
                                                       .at((*itMap).second.at(k))
                                                       .m_sbCqi.at(0)));
                    for (uint8_t j = 0; j < nLayer; j++)
                    {
                        if ((*itCqi)
                                .second.m_higherLayerSelected.at((*itMap).second.at(k))
                                .m_sbCqi.size() > j)
                        {
                            if (((*itCqi)
                                     .second.m_higherLayerSelected.at((*itMap).second.at(k))
                                     .m_sbCqi.at(j)) < worstCqi.at(j))
                            {
                                worstCqi.at(j) =
                                    ((*itCqi)
                                         .second.m_higherLayerSelected.at((*itMap).second.at(k))
                                         .m_sbCqi.at(j));
                            }
                        }
                        else
                        {
                            // no CQI for this layer of this suband -> worst one
                            worstCqi.at(j) = 1;
                        }
                    }
                }
                else
                {
                    for (uint8_t j = 0; j < nLayer; j++)
                    {
                        worstCqi.at(j) = 1; // try with lowest MCS in RBG with no info on channel
                    }
                }
            }
        }
        else
        {
            for (uint8_t j = 0; j < nLayer; j++)
            {
                worstCqi.at(j) = 1; // try with lowest MCS in RBG with no info on channel
            }
        }
        for (uint8_t j = 0; j < nLayer; j++)
        {
            NS_LOG_INFO(this << " Layer " << (uint16_t)j << " CQI selected "
                             << (uint16_t)worstCqi.at(j));
        }
        for (uint8_t j = 0; j < nLayer; j++)
        {
            newDci.m_mcs.push_back(m_amc->GetMcsFromCqi(worstCqi.at(j)));
            int tbSize = (m_amc->GetDlTbSizeFromMcs(newDci.m_mcs.at(j), RgbPerRnti * 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);
            NS_LOG_INFO(this << " Layer " << (uint16_t)j << " MCS selected"
                             << (uint16_t)m_amc->GetMcsFromCqi(worstCqi.at(j)));
        }
 
        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 (std::size_t k = 0; k < (*itMap).second.size(); k++)
        {
            rbgMask = rbgMask + (0x1 << (*itMap).second.at(k));
            NS_LOG_INFO(this << " Allocated RBG " << (*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)))
            {
                std::vector<RlcPduListElement_s> newRlcPduLe;
                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;
                    NS_LOG_INFO(this << " LCID " << (uint32_t)newRlcEl.m_logicalChannelIdentity
                                     << " size " << newRlcEl.m_size << " layer " << (uint16_t)j);
                    newRlcPduLe.push_back(newRlcEl);
                    UpdateDlRlcBufferInfo(newDci.m_rnti,
                                          newRlcEl.m_logicalChannelIdentity,
                                          newRlcEl.m_size);
                    if (m_harqOn)
                    {
                        // store RLC PDU list for HARQ
                        std::map<uint16_t, DlHarqRlcPduListBuffer_t>::iterator itRlcPdu =
                            m_dlHarqProcessesRlcPduListBuffer.find((*itMap).first);
                        if (itRlcPdu == m_dlHarqProcessesRlcPduListBuffer.end())
                        {
                            NS_FATAL_ERROR("Unable to find RlcPdcList in HARQ buffer for RNTI "
                                           << (*itMap).first);
                        }
                        (*itRlcPdu).second.at(j).at(newDci.m_harqProcess).push_back(newRlcEl);
                    }
                }
                newEl.m_rlcPduList.push_back(newRlcPduLe);
            }
            if ((*itBufReq).first.m_rnti > (*itMap).first)
            {
                break;
            }
        }
        for (uint8_t j = 0; j < nLayer; j++)
        {
            newDci.m_ndi.push_back(1);
            newDci.m_rv.push_back(0);
        }
 
        newDci.m_tpc = m_ffrSapProvider->GetTpc((*itMap).first);
 
        newEl.m_dci = newDci;
 
        if (m_harqOn)
        {
            // store DCI for HARQ
            std::map<uint16_t, DlHarqProcessesDciBuffer_t>::iterator itDci =
                m_dlHarqProcessesDciBuffer.find(newEl.m_rnti);
            if (itDci == m_dlHarqProcessesDciBuffer.end())
            {
                NS_FATAL_ERROR("Unable to find RNTI entry in DCI HARQ buffer for RNTI "
                               << newEl.m_rnti);
            }
            (*itDci).second.at(newDci.m_harqProcess) = newDci;
            // refresh timer
            std::map<uint16_t, DlHarqProcessesTimer_t>::iterator itHarqTimer =
                m_dlHarqProcessesTimer.find(newEl.m_rnti);
            if (itHarqTimer == m_dlHarqProcessesTimer.end())
            {
                NS_FATAL_ERROR("Unable to find HARQ timer for RNTI " << (uint16_t)newEl.m_rnti);
            }
            (*itHarqTimer).second.at(newDci.m_harqProcess) = 0;
        }
 
        // ...more parameters -> ignored in this version
 
        ret.m_buildDataList.push_back(newEl);
 
        itMap++;
    }                               // end while allocation
    ret.m_nrOfPdcchOfdmSymbols = 1; 
 
    m_schedSapUser->SchedDlConfigInd(ret);
}
 
void
FdTbfqFfMacScheduler::DoSchedDlRachInfoReq(
    const FfMacSchedSapProvider::SchedDlRachInfoReqParameters& params)
{
    NS_LOG_FUNCTION(this);
 
    m_rachList = params.m_rachList;
}
 
void
FdTbfqFfMacScheduler::DoSchedDlCqiInfoReq(
    const FfMacSchedSapProvider::SchedDlCqiInfoReqParameters& params)
{
    NS_LOG_FUNCTION(this);
    m_ffrSapProvider->ReportDlCqiInfo(params);
 
    for (unsigned int i = 0; i < params.m_cqiList.size(); i++)
    {
        if (params.m_cqiList.at(i).m_cqiType == CqiListElement_s::P10)
        {
            NS_LOG_LOGIC("wideband CQI " << (uint32_t)params.m_cqiList.at(i).m_wbCqi.at(0)
                                         << " reported");
            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");
        }
    }
}
 
double
FdTbfqFfMacScheduler::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;
        unsigned 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 = (sinrNum > 0) ? (sinrSum / sinrNum) : DBL_MAX;
        // store the value
        (*itCqi).second.at(rb) = estimatedSinr;
        return (estimatedSinr);
    }
}
 
void
FdTbfqFfMacScheduler::DoSchedUlTriggerReq(
    const FfMacSchedSapProvider::SchedUlTriggerReqParameters& params)
{
    NS_LOG_FUNCTION(this << " UL - Frame no. " << (params.m_sfnSf >> 4) << " subframe no. "
                         << (0xF & params.m_sfnSf) << " size " << params.m_ulInfoList.size());
 
    RefreshUlCqiMaps();
    m_ffrSapProvider->ReportUlCqiInfo(m_ueCqi);
 
    // Generate RBs map
    FfMacSchedSapUser::SchedUlConfigIndParameters ret;
    std::vector<bool> rbMap;
    uint16_t rbAllocatedNum = 0;
    std::set<uint16_t> rntiAllocated;
    std::vector<uint16_t> rbgAllocationMap;
    // update with RACH allocation map
    rbgAllocationMap = m_rachAllocationMap;
    // rbgAllocationMap.resize (m_cschedCellConfig.m_ulBandwidth, 0);
    m_rachAllocationMap.clear();
    m_rachAllocationMap.resize(m_cschedCellConfig.m_ulBandwidth, 0);
 
    rbMap.resize(m_cschedCellConfig.m_ulBandwidth, false);
 
    rbMap = m_ffrSapProvider->GetAvailableUlRbg();
 
    for (std::vector<bool>::iterator it = rbMap.begin(); it != rbMap.end(); it++)
    {
        if (*it)
        {
            rbAllocatedNum++;
        }
    }
 
    uint8_t minContinuousUlBandwidth = m_ffrSapProvider->GetMinContinuousUlBandwidth();
    uint8_t ffrUlBandwidth = m_cschedCellConfig.m_ulBandwidth - rbAllocatedNum;
 
    // remove RACH allocation
    for (uint16_t i = 0; i < m_cschedCellConfig.m_ulBandwidth; i++)
    {
        if (rbgAllocationMap.at(i) != 0)
        {
            rbMap.at(i) = true;
            NS_LOG_DEBUG(this << " Allocated for RACH " << i);
        }
    }
 
    if (m_harqOn)
    {
        //   Process UL HARQ feedback
        for (std::size_t i = 0; i < params.m_ulInfoList.size(); i++)
        {
            if (params.m_ulInfoList.at(i).m_receptionStatus == UlInfoListElement_s::NotOk)
            {
                // retx correspondent block: retrieve the UL-DCI
                uint16_t rnti = params.m_ulInfoList.at(i).m_rnti;
                std::map<uint16_t, uint8_t>::iterator itProcId =
                    m_ulHarqCurrentProcessId.find(rnti);
                if (itProcId == m_ulHarqCurrentProcessId.end())
                {
                    NS_LOG_ERROR("No info find in HARQ buffer for UE (might change eNB) " << rnti);
                }
                uint8_t harqId = (uint8_t)((*itProcId).second - HARQ_PERIOD) % HARQ_PROC_NUM;
                NS_LOG_INFO(this << " UL-HARQ retx RNTI " << rnti << " harqId " << (uint16_t)harqId
                                 << " i " << i << " size " << params.m_ulInfoList.size());
                std::map<uint16_t, UlHarqProcessesDciBuffer_t>::iterator itHarq =
                    m_ulHarqProcessesDciBuffer.find(rnti);
                if (itHarq == m_ulHarqProcessesDciBuffer.end())
                {
                    NS_LOG_ERROR("No info find in HARQ buffer for UE (might change eNB) " << rnti);
                    continue;
                }
                UlDciListElement_s dci = (*itHarq).second.at(harqId);
                std::map<uint16_t, UlHarqProcessesStatus_t>::iterator itStat =
                    m_ulHarqProcessesStatus.find(rnti);
                if (itStat == m_ulHarqProcessesStatus.end())
                {
                    NS_LOG_ERROR("No info find in HARQ buffer for UE (might change eNB) " << rnti);
                }
                if ((*itStat).second.at(harqId) >= 3)
                {
                    NS_LOG_INFO("Max number of retransmissions reached (UL)-> drop process");
                    continue;
                }
                bool free = true;
                for (int j = dci.m_rbStart; j < dci.m_rbStart + dci.m_rbLen; j++)
                {
                    if (rbMap.at(j))
                    {
                        free = false;
                        NS_LOG_INFO(this << " BUSY " << j);
                    }
                }
                if (free)
                {
                    // retx on the same RBs
                    for (int j = dci.m_rbStart; j < dci.m_rbStart + dci.m_rbLen; j++)
                    {
                        rbMap.at(j) = true;
                        rbgAllocationMap.at(j) = dci.m_rnti;
                        NS_LOG_INFO("\tRB " << j);
                        rbAllocatedNum++;
                    }
                    NS_LOG_INFO(this << " Send retx in the same RBs " << (uint16_t)dci.m_rbStart
                                     << " to " << dci.m_rbStart + dci.m_rbLen << " RV "
                                     << (*itStat).second.at(harqId) + 1);
                }
                else
                {
                    NS_LOG_INFO("Cannot allocate retx due to RACH allocations for UE " << rnti);
                    continue;
                }
                dci.m_ndi = 0;
                // Update HARQ buffers with new HarqId
                (*itStat).second.at((*itProcId).second) = (*itStat).second.at(harqId) + 1;
                (*itStat).second.at(harqId) = 0;
                (*itHarq).second.at((*itProcId).second) = dci;
                ret.m_dciList.push_back(dci);
                rntiAllocated.insert(dci.m_rnti);
            }
            else
            {
                NS_LOG_INFO(this << " HARQ-ACK feedback from RNTI "
                                 << params.m_ulInfoList.at(i).m_rnti);
            }
        }
    }
 
    std::map<uint16_t, uint32_t>::iterator it;
    int nflows = 0;
 
    for (it = m_ceBsrRxed.begin(); it != m_ceBsrRxed.end(); it++)
    {
        std::set<uint16_t>::iterator itRnti = rntiAllocated.find((*it).first);
        // select UEs with queues not empty and not yet allocated for HARQ
        if (((*it).second > 0) && (itRnti == rntiAllocated.end()))
        {
            nflows++;
        }
    }
 
    if (nflows == 0)
    {
        if (!ret.m_dciList.empty())
        {
            m_allocationMaps.insert(
                std::pair<uint16_t, std::vector<uint16_t>>(params.m_sfnSf, rbgAllocationMap));
            m_schedSapUser->SchedUlConfigInd(ret);
        }
 
        return; // no flows to be scheduled
    }
 
    // Divide the remaining resources equally among the active users starting from the subsequent
    // one served last scheduling trigger
    uint16_t tempRbPerFlow = (ffrUlBandwidth) / (nflows + rntiAllocated.size());
    uint16_t rbPerFlow =
        (minContinuousUlBandwidth < tempRbPerFlow) ? minContinuousUlBandwidth : tempRbPerFlow;
 
    if (rbPerFlow < 3)
    {
        rbPerFlow = 3; // at least 3 rbg per flow (till available resource) to ensure TxOpportunity
                       // >= 7 bytes
    }
    int rbAllocated = 0;
 
    std::map<uint16_t, fdtbfqsFlowPerf_t>::iterator itStats;
    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
    {
        std::set<uint16_t>::iterator itRnti = rntiAllocated.find((*it).first);
        if ((itRnti != rntiAllocated.end()) || ((*it).second == 0))
        {
            // UE already allocated for UL-HARQ -> skip it
            NS_LOG_DEBUG(this << " UE already allocated in HARQ -> discarded, RNTI "
                              << (*it).first);
            it++;
            if (it == m_ceBsrRxed.end())
            {
                // restart from the first
                it = m_ceBsrRxed.begin();
            }
            continue;
        }
        if (rbAllocated + rbPerFlow - 1 > m_cschedCellConfig.m_ulBandwidth)
        {
            // limit to physical resources last resource assignment
            rbPerFlow = m_cschedCellConfig.m_ulBandwidth - rbAllocated;
            // at least 3 rbg per flow to ensure TxOpportunity >= 7 bytes
            if (rbPerFlow < 3)
            {
                // terminate allocation
                rbPerFlow = 0;
            }
        }
 
        rbAllocated = 0;
        UlDciListElement_s uldci;
        uldci.m_rnti = (*it).first;
        uldci.m_rbLen = rbPerFlow;
        bool allocated = false;
        NS_LOG_INFO(this << " RB Allocated " << rbAllocated << " rbPerFlow " << rbPerFlow
                         << " flows " << nflows);
        while ((!allocated) && ((rbAllocated + rbPerFlow - m_cschedCellConfig.m_ulBandwidth) < 1) &&
               (rbPerFlow != 0))
        {
            // check availability
            bool free = true;
            for (int j = rbAllocated; j < rbAllocated + rbPerFlow; j++)
            {
                if (rbMap.at(j))
                {
                    free = false;
                    break;
                }
                if (!m_ffrSapProvider->IsUlRbgAvailableForUe(j, (*it).first))
                {
                    free = false;
                    break;
                }
            }
            if (free)
            {
                NS_LOG_INFO(this << "RNTI: " << (*it).first << " RB Allocated " << rbAllocated
                                 << " rbPerFlow " << rbPerFlow << " flows " << nflows);
                uldci.m_rbStart = rbAllocated;
 
                for (int j = rbAllocated; j < rbAllocated + rbPerFlow; j++)
                {
                    rbMap.at(j) = true;
                    // store info on allocation for managing ul-cqi interpretation
                    rbgAllocationMap.at(j) = (*it).first;
                }
                rbAllocated += rbPerFlow;
                allocated = true;
                break;
            }
            rbAllocated++;
            if (rbAllocated + rbPerFlow - 1 > m_cschedCellConfig.m_ulBandwidth)
            {
                // limit to physical resources last resource assignment
                rbPerFlow = m_cschedCellConfig.m_ulBandwidth - rbAllocated;
                // at least 3 rbg per flow to ensure TxOpportunity >= 7 bytes
                if (rbPerFlow < 3)
                {
                    // terminate allocation
                    rbPerFlow = 0;
                }
            }
        }
        if (!allocated)
        {
            // unable to allocate new resource: finish scheduling
            //          m_nextRntiUl = (*it).first;
            //          if (ret.m_dciList.size () > 0)
            //            {
            //              m_schedSapUser->SchedUlConfigInd (ret);
            //            }
            //          m_allocationMaps.insert (std::pair <uint16_t, std::vector <uint16_t> >
            //          (params.m_sfnSf, rbgAllocationMap)); return;
            break;
        }
 
        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)
            NS_ABORT_MSG_IF((*itCqi).second.empty(),
                            "CQI of RNTI = " << (*it).first << " has expired");
            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 (sinr < minSinr)
                {
                    minSinr = sinr;
                }
            }
 
            // 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();
                }
                NS_LOG_DEBUG(this << " UE discarded for CQI = 0, RNTI " << uldci.m_rnti);
                // remove UE from allocation map
                for (uint16_t i = uldci.m_rbStart; i < uldci.m_rbStart + uldci.m_rbLen; i++)
                {
                    rbgAllocationMap.at(i) = 0;
                }
                continue; // CQI == 0 means "out of range" (see table 7.2.3-1 of 36.213)
            }
            uldci.m_mcs = m_amc->GetMcsFromCqi(cqi);
        }
 
        uldci.m_tbSize = (m_amc->GetUlTbSizeFromMcs(uldci.m_mcs, rbPerFlow) / 8);
        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);
        // store DCI for HARQ_PERIOD
        uint8_t harqId = 0;
        if (m_harqOn)
        {
            std::map<uint16_t, uint8_t>::iterator itProcId;
            itProcId = m_ulHarqCurrentProcessId.find(uldci.m_rnti);
            if (itProcId == m_ulHarqCurrentProcessId.end())
            {
                NS_FATAL_ERROR("No info find in HARQ buffer for UE " << uldci.m_rnti);
            }
            harqId = (*itProcId).second;
            std::map<uint16_t, UlHarqProcessesDciBuffer_t>::iterator itDci =
                m_ulHarqProcessesDciBuffer.find(uldci.m_rnti);
            if (itDci == m_ulHarqProcessesDciBuffer.end())
            {
                NS_FATAL_ERROR("Unable to find RNTI entry in UL DCI HARQ buffer for RNTI "
                               << uldci.m_rnti);
            }
            (*itDci).second.at(harqId) = uldci;
            // Update HARQ process status (RV 0)
            std::map<uint16_t, UlHarqProcessesStatus_t>::iterator itStat =
                m_ulHarqProcessesStatus.find(uldci.m_rnti);
            if (itStat == m_ulHarqProcessesStatus.end())
            {
                NS_LOG_ERROR("No info find in HARQ buffer for UE (might change eNB) "
                             << uldci.m_rnti);
            }
            (*itStat).second.at(harqId) = 0;
        }
 
        NS_LOG_INFO(this << " UE Allocation RNTI " << (*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 << " harqId "
                         << (uint16_t)harqId);
 
        it++;
        if (it == m_ceBsrRxed.end())
        {
            // restart from the first
            it = m_ceBsrRxed.begin();
        }
        if ((rbAllocated == m_cschedCellConfig.m_ulBandwidth) || (rbPerFlow == 0))
        {
            // Stop allocation: no more PRBs
            m_nextRntiUl = (*it).first;
            break;
        }
    } while (((*it).first != m_nextRntiUl) && (rbPerFlow != 0));
 
    m_allocationMaps.insert(
        std::pair<uint16_t, std::vector<uint16_t>>(params.m_sfnSf, rbgAllocationMap));
    m_schedSapUser->SchedUlConfigInd(ret);
}
 
void
FdTbfqFfMacScheduler::DoSchedUlNoiseInterferenceReq(
    const FfMacSchedSapProvider::SchedUlNoiseInterferenceReqParameters& params)
{
    NS_LOG_FUNCTION(this);
}
 
void
FdTbfqFfMacScheduler::DoSchedUlSrInfoReq(
    const FfMacSchedSapProvider::SchedUlSrInfoReqParameters& params)
{
    NS_LOG_FUNCTION(this);
}
 
void
FdTbfqFfMacScheduler::DoSchedUlMacCtrlInfoReq(
    const 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 this scheduler does not differentiate the
            // allocation according to which LCGs have more/less bytes
            // to send.
            // Hence the BSR of different LCGs are just summed up to get
            // a total queue size that is used for allocation purposes.
 
            uint32_t buffer = 0;
            for (uint8_t lcg = 0; lcg < 4; ++lcg)
            {
                uint8_t bsrId = params.m_macCeList.at(i).m_macCeValue.m_bufferStatus.at(lcg);
                buffer += BufferSizeLevelBsr::BsrId2BufferSize(bsrId);
            }
 
            uint16_t rnti = params.m_macCeList.at(i).m_rnti;
            NS_LOG_LOGIC(this << "RNTI=" << rnti << " buffer=" << buffer);
            it = m_ceBsrRxed.find(rnti);
            if (it == m_ceBsrRxed.end())
            {
                // create the new entry
                m_ceBsrRxed.insert(std::pair<uint16_t, uint32_t>(rnti, buffer));
            }
            else
            {
                // update the buffer size value
                (*it).second = buffer;
            }
        }
    }
}
 
void
FdTbfqFfMacScheduler::DoSchedUlCqiInfoReq(
    const 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;
        }
    }
    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;
        NS_LOG_DEBUG(this << " Collect PUSCH CQIs of Frame no. " << (params.m_sfnSf >> 4)
                          << " subframe no. " << (0xF & params.m_sfnSf));
        itMap = m_allocationMaps.find(params.m_sfnSf);
        if (itMap == m_allocationMaps.end())
        {
            return;
        }
        for (uint32_t i = 0; i < (*itMap).second.size(); i++)
        {
            // convert from fixed point notation Sxxxxxxxxxxx.xxx to double
            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;
                NS_LOG_DEBUG(this << " RNTI " << (*itMap).second.at(i) << " RB " << i << " SINR "
                                  << 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.empty());
        for (std::size_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_INFO(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_INFO(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("FdTbfqFfMacScheduler supports only PUSCH and SRS UL-CQIs");
    }
    break;
    default:
        NS_FATAL_ERROR("Unknown type of UL-CQI");
    }
}
 
void
FdTbfqFfMacScheduler::RefreshDlCqiMaps()
{
    // 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 expired 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 expired 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++;
        }
    }
}
 
void
FdTbfqFfMacScheduler::RefreshUlCqiMaps()
{
    // 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++;
        }
    }
}
 
void
FdTbfqFfMacScheduler::UpdateDlRlcBufferInfo(uint16_t rnti, uint8_t lcid, uint16_t size)
{
    std::map<LteFlowId_t, FfMacSchedSapProvider::SchedDlRlcBufferReqParameters>::iterator it;
    LteFlowId_t flow(rnti, lcid);
    it = m_rlcBufferReq.find(flow);
    if (it != m_rlcBufferReq.end())
    {
        NS_LOG_INFO(this << " UE " << rnti << " LC " << (uint16_t)lcid << " txqueue "
                         << (*it).second.m_rlcTransmissionQueueSize << " retxqueue "
                         << (*it).second.m_rlcRetransmissionQueueSize << " status "
                         << (*it).second.m_rlcStatusPduSize << " decrease " << size);
        // Update queues: RLC tx order Status, ReTx, Tx
        // Update status queue
        if (((*it).second.m_rlcStatusPduSize > 0) && (size >= (*it).second.m_rlcStatusPduSize))
        {
            (*it).second.m_rlcStatusPduSize = 0;
        }
        else if (((*it).second.m_rlcRetransmissionQueueSize > 0) &&
                 (size >= (*it).second.m_rlcRetransmissionQueueSize))
        {
            (*it).second.m_rlcRetransmissionQueueSize = 0;
        }
        else if ((*it).second.m_rlcTransmissionQueueSize > 0)
        {
            uint32_t rlcOverhead;
            if (lcid == 1)
            {
                // for SRB1 (using RLC AM) it's better to
                // overestimate RLC overhead rather than
                // underestimate it and risk unneeded
                // segmentation which increases delay
                rlcOverhead = 4;
            }
            else
            {
                // minimum RLC overhead due to header
                rlcOverhead = 2;
            }
            // update transmission queue
            if ((*it).second.m_rlcTransmissionQueueSize <= size - rlcOverhead)
            {
                (*it).second.m_rlcTransmissionQueueSize = 0;
            }
            else
            {
                (*it).second.m_rlcTransmissionQueueSize -= size - rlcOverhead;
            }
        }
    }
    else
    {
        NS_LOG_ERROR(this << " Does not find DL RLC Buffer Report of UE " << rnti);
    }
}
 
void
FdTbfqFfMacScheduler::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())
    {
        NS_LOG_INFO(this << " UE " << rnti << " size " << size << " BSR " << (*it).second);
        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
FdTbfqFfMacScheduler::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);
}
 
} // namespace ns3