BreakpointPathlossModel.cc

#include "BreakpointPathlossModel.h"

#define debugEV (ev.isDisabled()||!debug) ? ev : ev << "PhyLayer(BreakpointPathlossModel): "


void BreakpointPathlossModel::filterSignal(Signal& s) {

  simtime_t sStart = s.getSignalStart();
  simtime_t sEnd = s.getSignalLength() + sStart;

  Coord sendersPos = s.getMove().getPositionAt(sStart);
  Coord myPos = myMove.getPositionAt(sStart);

  double distance = useTorus ? myPos.sqrTorusDist(sendersPos, playgroundSize)
                  : myPos.sqrdist(sendersPos);
  distance = sqrt(distance);
  debugEV << "distance is: " << distance << endl;

  if(distance <= 1.0) {
    //attenuation is negligible
    return;
  }

  double attenuation = 1;
  // PL(d) = PL0 + 10 alpha log10 (d/d0)
  // 10 ^ { PL(d)/10 } = 10 ^{PL0 + 10 alpha log10 (d/d0)}/10
  // 10 ^ { PL(d)/10 } = 10 ^ PL0/10 * 10 ^ { 10 log10 (d/d0)^alpha }/10
  // 10 ^ { PL(d)/10 } = 10 ^ PL0/10 * 10 ^ { log10 (d/d0)^alpha }
  // 10 ^ { PL(d)/10 } = 10 ^ PL0/10 * (d/d0)^alpha
  if(distance < breakpointDistance) {
    attenuation = attenuation * PL01_real;
    attenuation = attenuation * pow(distance, alpha1);
  } else {
    attenuation = attenuation * PL02_real;
    attenuation = attenuation * pow(distance/breakpointDistance, alpha2);
  }
  attenuation = 1/attenuation;
  debugEV << "attenuation is: " << attenuation << endl;

  if(debug) {
    pathlosses.record(10*log10(attenuation)); // in dB
  }

  const DimensionSet& domain = DimensionSet::timeDomain;
  Argument arg; // default constructor initializes with a single dimension, time, and value 0 (offset from signal start)
  TimeMapping<Linear>* attMapping = new TimeMapping<Linear> (); // mapping performs a linear interpolation from our single point -> constant
  attMapping->setValue(arg, attenuation);

  /* at last add the created attenuation mapping to the signal */
  s.addAttenuation(attMapping);
}