HGCFEElectronics.cc

#include "SimCalorimetry/HGCalSimProducers/interface/HGCFEElectronics.h"
#include "DataFormats/HGCDigi/interface/HGCDigiCollections.h"
#include "FWCore/Utilities/interface/transform.h"

#include "vdt/vdtMath.h"

using namespace hgc_digi;

//
template <class DFr>
HGCFEElectronics<DFr>::HGCFEElectronics(const edm::ParameterSet& ps)
    : fwVersion_{ps.getParameter<uint32_t>("fwVersion")},
      adcPulse_{},
      pulseAvgT_{},
      tdcForToAOnset_fC_{},
      adcSaturation_fC_{-1.0},
      adcLSB_fC_{},
      tdcLSB_fC_{},
      tdcSaturation_fC_{-1.0},
      adcThreshold_fC_{},
      tdcOnset_fC_{},
      toaLSB_ns_{},
      tdcResolutionInNs_{1e-9},  // set time resolution very small by default
      targetMIPvalue_ADC_{},
      jitterNoise_ns_{},
      jitterConstant_ns_{},
      eventTimeOffset_ns_{{0.02, 0.02, 0.02}},
      noise_fC_{},
      toaMode_(WEIGHTEDBYE) {
  edm::LogVerbatim("HGCFE") << "[HGCFEElectronics] running with version " << fwVersion_ << std::endl;
  if (ps.exists("adcPulse")) {
    auto temp = ps.getParameter<std::vector<double> >("adcPulse");
    for (unsigned i = 0; i < temp.size(); ++i) {
      adcPulse_[i] = (float)temp[i];
    }
    // normalize adc pulse
    for (unsigned i = 0; i < adcPulse_.size(); ++i) {
      adcPulse_[i] = adcPulse_[i] / adcPulse_[2];
    }
    temp = ps.getParameter<std::vector<double> >("pulseAvgT");
    for (unsigned i = 0; i < temp.size(); ++i) {
      pulseAvgT_[i] = (float)temp[i];
    }
  }
  if (ps.exists("adcNbits")) {
    uint32_t adcNbits = ps.getParameter<uint32_t>("adcNbits");
    adcSaturation_fC_ = ps.getParameter<double>("adcSaturation_fC");
    adcLSB_fC_ = adcSaturation_fC_ / pow(2., adcNbits);
    edm::LogVerbatim("HGCFE") << "[HGCFEElectronics] " << adcNbits << " bit ADC defined"
                              << " with LSB=" << adcLSB_fC_ << " saturation to occur @ " << adcSaturation_fC_
                              << std::endl;
  }

  if (ps.exists("tdcNbits")) {
    tdcNbits_ = ps.getParameter<uint32_t>("tdcNbits");
    setTDCfsc(ps.getParameter<double>("tdcSaturation_fC"));
    edm::LogVerbatim("HGCFE") << "[HGCFEElectronics] " << tdcNbits_ << " bit TDC defined with LSB=" << tdcLSB_fC_
                              << " saturation to occur @ " << tdcSaturation_fC_
                              << " (NB lowered by 1 part in a million)" << std::endl;
  }
  if (ps.exists("targetMIPvalue_ADC"))
    targetMIPvalue_ADC_ = ps.getParameter<uint32_t>("targetMIPvalue_ADC");
  if (ps.exists("adcThreshold_fC"))
    adcThreshold_fC_ = ps.getParameter<double>("adcThreshold_fC");
  if (ps.exists("tdcOnset_fC"))
    tdcOnset_fC_ = ps.getParameter<double>("tdcOnset_fC");
  if (ps.exists("tdcForToAOnset_fC")) {
    auto temp = ps.getParameter<std::vector<double> >("tdcForToAOnset_fC");
    if (temp.size() == tdcForToAOnset_fC_.size()) {
      std::copy_n(temp.begin(), temp.size(), tdcForToAOnset_fC_.begin());
    } else {
      throw cms::Exception("BadConfiguration") << " HGCFEElectronics wrong size for ToA thresholds ";
    }
  }
  if (ps.exists("toaLSB_ns"))
    toaLSB_ns_ = ps.getParameter<double>("toaLSB_ns");
  if (ps.exists("tdcChargeDrainParameterisation")) {
    for (auto val : ps.getParameter<std::vector<double> >("tdcChargeDrainParameterisation")) {
      tdcChargeDrainParameterisation_.push_back((float)val);
    }
  }
  if (ps.exists("tdcResolutionInPs"))
    tdcResolutionInNs_ = ps.getParameter<double>("tdcResolutionInPs") * 1e-3;  // convert to ns
  if (ps.exists("toaMode"))
    toaMode_ = ps.getParameter<uint32_t>("toaMode");

  if (ps.exists("jitterNoise_ns")) {
    auto temp = ps.getParameter<std::vector<double> >("jitterNoise_ns");
    if (temp.size() == jitterNoise_ns_.size()) {
      std::copy_n(temp.begin(), temp.size(), jitterNoise_ns_.begin());
    } else {
      throw cms::Exception("BadConfiguration") << " HGCFEElectronics wrong size for ToA jitterNoise ";
    }
  }
  if (ps.exists("jitterConstant_ns")) {
    auto temp = ps.getParameter<std::vector<double> >("jitterConstant_ns");
    if (temp.size() == jitterConstant_ns_.size()) {
      std::copy_n(temp.begin(), temp.size(), jitterConstant_ns_.begin());
    } else {
      throw cms::Exception("BadConfiguration") << " HGCFEElectronics wrong size for ToA jitterConstant ";
    }
  }
}

//
template <class DFr>
void HGCFEElectronics<DFr>::runTrivialShaper(
    DFr& dataFrame, HGCSimHitData& chargeColl, uint32_t thrADC, float lsbADC, uint32_t gainIdx, float maxADC) {
  bool debug(false);

#ifdef EDM_ML_DEBUG
  for (int it = 0; it < (int)(chargeColl.size()); it++)
    debug |= (chargeColl[it] > adcThreshold_fC_);
#endif

  if (debug)
    edm::LogVerbatim("HGCFE") << "[runTrivialShaper]" << std::endl;

  if (lsbADC < 0)
    lsbADC = adcLSB_fC_;
  if (maxADC < 0)
    // lower adcSaturation_fC_ by one part in a million
    // to ensure largest charge converted in bits is 0xfff==4095, not 0x1000
    // no effect on charges loewer than; no impact on cpu time, only done once
    maxADC = adcSaturation_fC_ * (1 - 1e-6);
  for (int it = 0; it < (int)(chargeColl.size()); it++) {
    //brute force saturation, maybe could to better with an exponential like saturation
    const uint32_t adc = std::floor(std::min(chargeColl[it], maxADC) / lsbADC);
    HGCSample newSample;
    newSample.set(adc > thrADC, false, gainIdx, 0, adc);
    dataFrame.setSample(it, newSample);

    if (debug)
      edm::LogVerbatim("HGCFE") << adc << " (" << chargeColl[it] << "/" << adcLSB_fC_ << ") ";
  }

  if (debug) {
    std::ostringstream msg;
    dataFrame.print(msg);
    edm::LogVerbatim("HGCFE") << msg.str() << std::endl;
  }
}

//
template <class DFr>
void HGCFEElectronics<DFr>::runSimpleShaper(DFr& dataFrame,
                                            HGCSimHitData& chargeColl,
                                            uint32_t thrADC,
                                            float lsbADC,
                                            uint32_t gainIdx,
                                            float maxADC,
                                            const hgc_digi::FEADCPulseShape& adcPulse) {
  //convolute with pulse shape to compute new ADCs
  newCharge.fill(0.f);
  bool debug(false);
  for (int it = 0; it < (int)(chargeColl.size()); it++) {
    const float charge(chargeColl[it]);
    if (charge == 0.f)
      continue;

#ifdef EDM_ML_DEBUG
    debug |= (charge > adcThreshold_fC_);
#endif

    if (debug)
      edm::LogVerbatim("HGCFE") << "\t Redistributing SARS ADC" << charge << " @ " << it;

    for (int ipulse = -2; ipulse < (int)(adcPulse.size()) - 2; ipulse++) {
      if (it + ipulse < 0)
        continue;
      if (it + ipulse >= (int)(dataFrame.size()))
        continue;
      const float chargeLeak = charge * adcPulse[(ipulse + 2)];
      newCharge[it + ipulse] += chargeLeak;

      if (debug)
        edm::LogVerbatim("HGCFE") << " | " << it + ipulse << " " << chargeLeak;
    }

    if (debug)
      edm::LogVerbatim("HGCFE") << std::endl;
  }

  for (int it = 0; it < (int)(newCharge.size()); it++) {
    //brute force saturation, maybe could to better with an exponential like saturation
    const uint32_t adc = std::floor(std::min(newCharge[it], maxADC) / lsbADC);
    HGCSample newSample;
    newSample.set(adc > thrADC, false, gainIdx, 0, adc);
    dataFrame.setSample(it, newSample);

    if (debug)
      edm::LogVerbatim("HGCFE") << adc << " (" << std::min(newCharge[it], maxADC) << "/" << lsbADC << " ) ";
  }

  if (debug) {
    std::ostringstream msg;
    dataFrame.print(msg);
    edm::LogVerbatim("HGCFE") << msg.str() << std::endl;
  }
}

//
template <class DFr>
void HGCFEElectronics<DFr>::runShaperWithToT(DFr& dataFrame,
                                             HGCSimHitData& chargeColl,
                                             HGCSimHitData& toaColl,
                                             CLHEP::HepRandomEngine* engine,
                                             uint32_t thrADC,
                                             float lsbADC,
                                             uint32_t gainIdx,
                                             float maxADC,
                                             int thickness,
                                             float tdcOnsetAuto,
                                             float noiseWidth,
                                             const hgc_digi::FEADCPulseShape& adcPulse) {
  busyFlags.fill(false);
  totFlags.fill(false);
  toaFlags.fill(false);
  newCharge.fill(0.f);
  toaFromToT.fill(0.f);

#ifdef EDM_ML_DEBUG
  constexpr bool debug_state(true);
#else
  constexpr bool debug_state(false);
#endif

  bool debug = debug_state;

  float timeToA = 0.f;

  //configure the ADC <-> TDC transition depending on the value passed as argument
  double tdcOnset(maxADC);
  if (maxADC < 0) {
    maxADC = adcSaturation_fC_;
    tdcOnset = tdcOnset_fC_;
  }

  //configure the ADC LSB depending on the value passed as argument
  if (lsbADC < 0)
    lsbADC = adcLSB_fC_;

  //first look at time
  //for pileup look only at intime signals
  //ToA is in central BX if fired -- std::floor(BX/25.)+9;
  int fireBX = 9;
  //noise fluctuation on charge is added after ToA computation
  //do not recheck the ToA firing threshold tdcForToAOnset_fC_[thickness-1] not to bias the efficiency
  //to be done properly with realistic ToA shaper and jitter for the moment accounted in the smearing
  if (toaColl[fireBX] != 0.f) {
    timeToA = toaColl[fireBX];
    float sensor_noise = noiseWidth <= 0 ? noise_fC_[thickness - 1] : noiseWidth;
    float noise = jitterNoise_ns_[thickness - 1] * sensor_noise;
    float jitter = chargeColl[fireBX] == 0 ? 0 : (noise / chargeColl[fireBX]);
    if (jitter != 0)
      timeToA = CLHEP::RandGaussQ::shoot(engine, timeToA, jitter);
    else if (tdcResolutionInNs_ != 0)
      timeToA = CLHEP::RandGaussQ::shoot(engine, timeToA, tdcResolutionInNs_);
    timeToA += eventTimeOffset_ns_[thickness - 1];
    if (timeToA >= 0.f && timeToA <= 25.f)
      toaFlags[fireBX] = true;
  }

  //now look at charge
  //first identify bunches which will trigger ToT
  //if(debug_state) edm::LogVerbatim("HGCFE") << "[runShaperWithToT]" << std::endl;
  for (int it = 0; it < (int)(chargeColl.size()); ++it) {
    debug = debug_state;
    //if already flagged as busy it can't be re-used to trigger the ToT
    if (busyFlags[it])
      continue;

    if (tdcOnsetAuto < 0) {
      tdcOnsetAuto = tdcOnset_fC_;
    }
    //if below TDC onset will be handled by SARS ADC later
    float charge = chargeColl[it];
    if (charge < tdcOnset) {
      debug = false;
      continue;
    }

    //raise TDC mode for charge computation
    //ToA anyway fired independently will be sorted out with realistic ToA dedicated shaper
    float toa = timeToA;
    totFlags[it] = true;

    if (debug)
      edm::LogVerbatim("HGCFE") << "\t q=" << charge << " fC with <toa>=" << toa << " ns, triggers ToT @ " << it
                                << std::endl;

    //compute total charge to be integrated and integration time
    //needs a loop as ToT will last as long as there is charge to dissipate
    int busyBxs(0);
    float totalCharge(charge), finalToA(toa), integTime(0);
    while (true) {
      //compute integration time in ns and # bunches
      //float newIntegTime(0);
      int poffset = 0;
      float charge_offset = 0.f;
      const float charge_kfC(totalCharge * 1e-3);
      if (charge_kfC < tdcChargeDrainParameterisation_[3]) {
        //newIntegTime=tdcChargeDrainParameterisation_[0]*pow(charge_kfC,2)+tdcChargeDrainParameterisation_[1]*charge_kfC+tdcChargeDrainParameterisation_[2];
      } else if (charge_kfC < tdcChargeDrainParameterisation_[7]) {
        poffset = 4;
        charge_offset = tdcChargeDrainParameterisation_[3];
        //newIntegTime=tdcChargeDrainParameterisation_[4]*pow(charge_kfC-tdcChargeDrainParameterisation_[3],2)+tdcChargeDrainParameterisation_[5]*(charge_kfC-tdcChargeDrainParameterisation_[3])+tdcChargeDrainParameterisation_[6];
      } else {
        poffset = 8;
        charge_offset = tdcChargeDrainParameterisation_[7];
        //newIntegTime=tdcChargeDrainParameterisation_[8]*pow(charge_kfC-tdcChargeDrainParameterisation_[7],2)+tdcChargeDrainParameterisation_[9]*(charge_kfC-tdcChargeDrainParameterisation_[7])+tdcChargeDrainParameterisation_[10];
      }
      const float charge_mod = charge_kfC - charge_offset;
      const float newIntegTime =
          ((tdcChargeDrainParameterisation_[poffset] * charge_mod + tdcChargeDrainParameterisation_[poffset + 1]) *
               charge_mod +
           tdcChargeDrainParameterisation_[poffset + 2]);

      const int newBusyBxs = std::floor(newIntegTime / 25.f) + 1;

      //if no update is needed regarding the number of bunches,
      //then the ToT integration time has converged
      integTime = newIntegTime;
      if (newBusyBxs == busyBxs)
        break;

      //update charge integrated during ToT
      if (debug) {
        if (busyBxs == 0)
          edm::LogVerbatim("HGCFE") << "\t Intial busy estimate=" << integTime << " ns = " << newBusyBxs << " bxs"
                                    << std::endl;
        else
          edm::LogVerbatim("HGCFE") << "\t ...integrated charge overflows initial busy estimate, interating again"
                                    << std::endl;
      }

      //update number of busy bunches
      busyBxs = newBusyBxs;

      //reset charge to be integrated
      totalCharge = charge;
      if (toaMode_ == WEIGHTEDBYE)
        finalToA = toa * charge;

      //add leakage from previous bunches in SARS ADC mode
      for (int jt = 0; jt < it; ++jt) {
        const unsigned int deltaT = (it - jt);
        if ((deltaT + 2) >= adcPulse.size() || chargeColl[jt] == 0.f || totFlags[jt] || busyFlags[jt])
          continue;

        const float leakCharge = chargeColl[jt] * adcPulse[deltaT + 2];
        totalCharge += leakCharge;
        if (toaMode_ == WEIGHTEDBYE)
          finalToA += leakCharge * pulseAvgT_[deltaT + 2];

        if (debug)
          edm::LogVerbatim("HGCFE") << "\t\t leaking " << chargeColl[jt] << " fC @ deltaT=-" << deltaT << " -> +"
                                    << leakCharge << " with avgT=" << pulseAvgT_[deltaT + 2] << std::endl;
      }

      //add contamination from posterior bunches
      for (int jt = it + 1; jt < it + busyBxs && jt < dataFrame.size(); ++jt) {
        //this charge will be integrated in TDC mode
        //disable for SARS ADC
        busyFlags[jt] = true;

        const float extraCharge = chargeColl[jt];
        if (extraCharge == 0.f)
          continue;
        if (debug)
          edm::LogVerbatim("HGCFE") << "\t\t adding " << extraCharge << " fC @ deltaT=+" << (jt - it) << std::endl;

        totalCharge += extraCharge;
        if (toaMode_ == WEIGHTEDBYE)
          finalToA += extraCharge * toaColl[jt];
      }

      //finalize ToA contamination
      if (toaMode_ == WEIGHTEDBYE)
        finalToA /= totalCharge;
    }

    newCharge[it] = (totalCharge - tdcOnset);

    if (debug)
      edm::LogVerbatim("HGCFE") << "\t Final busy estimate=" << integTime << " ns = " << busyBxs << " bxs" << std::endl
                                << "\t Total integrated=" << totalCharge << " fC <toa>=" << toaFromToT[it]
                                << " (raw=" << finalToA << ") ns " << std::endl;

    //last fC (tdcOnset) are dissipated trough pulse
    if (it + busyBxs < (int)(newCharge.size())) {
      const float deltaT2nextBx((busyBxs * 25 - integTime));
      const float tdcOnsetLeakage(tdcOnset * vdt::fast_expf(-deltaT2nextBx / tdcChargeDrainParameterisation_[11]));
      if (debug)
        edm::LogVerbatim("HGCFE") << "\t Leaking remainder of TDC onset " << tdcOnset << " fC, to be dissipated in "
                                  << deltaT2nextBx << " DeltaT/tau=" << deltaT2nextBx << " / "
                                  << tdcChargeDrainParameterisation_[11] << " ns, adds " << tdcOnsetLeakage << " fC @ "
                                  << it + busyBxs << " bx (first free bx)" << std::endl;
      newCharge[it + busyBxs] += tdcOnsetLeakage;
    }
  }

  //including the leakage from bunches in SARS ADC when not declared busy or in ToT
  auto runChargeSharing = [&]() {
    int ipulse = 0;
    for (int it = 0; it < (int)(chargeColl.size()); ++it) {
      //if busy, charge has been already integrated
      //if(debug) edm::LogVerbatim("HGCFE") << "\t SARS ADC pulse activated @ " << it << " : ";
      if (!totFlags[it] & !busyFlags[it]) {
        const int start = std::max(0, 2 - it);
        const int stop = std::min((int)adcPulse.size(), (int)newCharge.size() - it + 2);
        for (ipulse = start; ipulse < stop; ++ipulse) {
          const int itoffset = it + ipulse - 2;
          //notice that if the channel is already busy,
          //it has already been affected by the leakage of the SARS ADC
          //if(totFlags[itoffset] || busyFlags[itoffset]) continue;
          if (!totFlags[itoffset] & !busyFlags[itoffset]) {
            newCharge[itoffset] += chargeColl[it] * adcPulse[ipulse];
          }
          //if(debug) edm::LogVerbatim("HGCFE") << " | " << itoffset << " " << chargeColl[it]*adcPulse[ipulse] << "( " << chargeColl[it] << "->";
          //if(debug) edm::LogVerbatim("HGCFE") << newCharge[itoffset] << ") ";
        }
      }

      if (debug)
        edm::LogVerbatim("HGCFE") << std::endl;
    }
  };
  runChargeSharing();

  //For the future need to understand how to deal with toa for out of time signals
  //and for that should keep track of the BX firing the ToA somewhere (also to restore the use of finalToA)
  /*
  float finalToA(0.);
  for(int it=0; it<(int)(newCharge.size()); it++){
    if(toaFlags[it]){
      finalToA = toaFromToT[it];
      //to avoid +=25 for small negative time taken as 0
      while(finalToA < -1.e-5)  finalToA+=25.f;
      while(finalToA > 25.f) finalToA-=25.f;
      toaFromToT[it] = finalToA;
    }
  }
  */
  //timeToA is already in 0-25ns range by construction

  //set new ADCs and ToA
  if (debug)
    edm::LogVerbatim("HGCFE") << "\t final result : ";
  for (int it = 0; it < (int)(newCharge.size()); it++) {
    if (debug)
      edm::LogVerbatim("HGCFE") << chargeColl[it] << " -> " << newCharge[it] << " ";

    HGCSample newSample;
    if (totFlags[it] || busyFlags[it]) {
      if (totFlags[it]) {
        //brute force saturation, maybe could to better with an exponential like saturation
        const float saturatedCharge(std::min(newCharge[it], tdcSaturation_fC_));
        //working version for in-time PU and signal
        newSample.set(
            true, true, gainIdx, (uint16_t)(timeToA / toaLSB_ns_), (uint16_t)(std::floor(saturatedCharge / tdcLSB_fC_)));
        if (toaFlags[it])
          newSample.setToAValid(true);
      } else {
        newSample.set(false, true, gainIdx, 0, 0);
      }
    } else {
      //brute force saturation, maybe could to better with an exponential like saturation
      const uint16_t adc = std::floor(std::min(newCharge[it], maxADC) / lsbADC);
      //working version for in-time PU and signal
      newSample.set(adc > thrADC, false, gainIdx, (uint16_t)(timeToA / toaLSB_ns_), adc);
      if (toaFlags[it])
        newSample.setToAValid(true);
    }
    dataFrame.setSample(it, newSample);
  }

  if (debug) {
    std::ostringstream msg;
    dataFrame.print(msg);
    edm::LogVerbatim("HGCFE") << msg.str() << std::endl;
  }
}

// cause the compiler to generate the appropriate code
#include "DataFormats/HGCDigi/interface/HGCDigiCollections.h"
template class HGCFEElectronics<HGCalDataFrame>;