RSSI to distance

  const clearRSSIToM=-6; // Measured in dB/m. Line of sight change in dB per meter.
  const clearRSSIat1Meter=-63.462; //Measured in dB. Line of sight dB measurement at 1 meter from source.
  const clearPropagationConstant=12.27; //Propagation constant, 2 is clear line of sight in atmosphere near sea level.


  public function calculateDistanceFromRSSI($recievedRSSI, $dbAt1Meter=Triangulate::clearRSSIat1Meter, $clearRSSIToM = Triangulate::clearRSSIToM, $propagationConstant=Triangulate::clearPropagationConstant)
  //Calculates distance based off RSSI.
  {
    //RYOMA PLS
    //d=((A - RSSI) / (10n log(10)))
    //log10(d)
    //RSSI (dBm) = -10n log10(d) + A
    //return (($dbAt1Meter / $recievedRSSI) / (10*$propagationConstant * log(10)));
    $dbAt1Meter*=-1;
    $clearRSSIToM*=-1;
    return exp(($recievedRSSI + $dbAt1Meter) / $clearRSSIToM);
  }