//------------------------------------------------------------------------
RealArray PhysicalMeasurement::TroposphereCorrection(Real freq, Rvector3 rVec, Rmatrix Ro_j2k)
{
   RealArray tropoCorrection;

   if (troposphere != NULL)
   {
   	Real wavelength = GmatPhysicalConstants::SPEED_OF_LIGHT_VACUUM / (freq*1.0e6);
   	troposphere->SetWaveLength(wavelength);
   	Real elevationAngle = asin((Ro_j2k*rVec.GetUnitVector()).GetElement(2));
   	troposphere->SetElevationAngle(elevationAngle);
   	troposphere->SetRange(rVec.GetMagnitude()*GmatMathConstants::KM_TO_M);
   	tropoCorrection = troposphere->Correction();
//   	Real rangeCorrection = tropoCorrection[0]/GmatMathConstants::KM_TO_M;

		#ifdef DEBUG_RANGE_CALC_WITH_EVENTS
			MessageInterface::ShowMessage("       Apply Troposphere media correction:\n");
			MessageInterface::ShowMessage("         .Wave length = %.12lf m\n", wavelength);
			MessageInterface::ShowMessage("         .Elevation angle = %.12lf degree\n", elevationAngle*GmatMathConstants::DEG_PER_RAD);
			MessageInterface::ShowMessage("         .Range correction = %.12lf m\n", tropoCorrection[0]);
		#endif
   }
   else
   {
   	tropoCorrection.push_back(0.0);
   	tropoCorrection.push_back(0.0);
   	tropoCorrection.push_back(0.0);
   }

   return tropoCorrection;
}
Beispiel #2
0
Rmatrix33 NadirPointing::TRIAD(Rvector3& V1, Rvector3& V2, Rvector3& W1, Rvector3& W2)
{
	// V1, V2 : defined in frame A
	// W1, W2 : defined in frame B
	// TRIAD algorithm calculates the rotation matrix from A to B

	Rvector3 r1 = V1.GetUnitVector();
	Rvector3 temp = Cross(V1,V2);
	Rvector3 r2 = temp.GetUnitVector();
	Rvector3 r3 = Cross(V1,temp);
	r3 = r3.GetUnitVector();

	Rvector3 s1 = W1.GetUnitVector();
	temp = Cross(W1,W2);
	Rvector3 s2 = temp.GetUnitVector();
	Rvector3 s3 = Cross(W1,temp);
	s3 = s3.GetUnitVector();

	//MessageInterface::LogMessage("s3 = %f\t%f\t%f\n", s3(0), s3(1), s3(2) );

	// YRL, calculate resultRotMatrix
	Rmatrix33 resultRotMatrix = Outerproduct(s1,r1) + Outerproduct(s2,r2) + Outerproduct(s3,r3) ;	

	return resultRotMatrix;
}
Beispiel #3
0
//------------------------------------------------------------------------------
Real AngleUtil::ComputeAngleInDeg(const Rvector3 &vecA, const Rvector3 &vecB,
                                  Real tol)
{
   Rvector3 uvecA = vecA.GetUnitVector();
   Rvector3 uvecB = vecB.GetUnitVector();
   Real aDotB = uvecA * uvecB;
   Real angRad = 0.0;
   Real angDeg = 0.0;
   
   // if dot-product is less than or equal to tolerance, the angle is arccos of
   // the dot-product, otherwise, the angle is arcsin of the magnitude of the
   // cross-product.
   
   if (Abs(aDotB) <= Abs(tol))
   {
      angRad = ACos(aDotB);
      angDeg = DEG_PER_RAD * angRad;
   }
   else
   {
      // compute cross-product of two vectors
      Rvector3 aCrossB = Cross(uvecA, uvecB);
      Real crossMag = aCrossB.GetMagnitude();
      angRad = ASin(crossMag);

      if (aDotB < 0.0)
      {
         angRad = PI_OVER_TWO - angRad;
         angDeg = DEG_PER_RAD * angRad;
      }
   }
   
   return angDeg;
}
Beispiel #4
0
//------------------------------------------------------------------------------
bool Periapsis::Evaluate()
{
   if (mOrigin == NULL)
      OrbitData::InitializeRefObjects();
   
   Rvector6 cartState = OrbitData::GetRelativeCartState(mOrigin);
   
   //MessageInterface::ShowMessage
   //   (wxT("===> Periapsis::Evaluate() mOrigin=%s, cartState=%s\n"),
   //    mOrigin->GetName().c_str(), cartState.ToString().c_str());
   
   if (cartState == Rvector6::RVECTOR6_UNDEFINED)
      return false;
   
   // compute position and velocity unit vectors
   Rvector3 pos = Rvector3(cartState[0], cartState[1], cartState[2]);
   Rvector3 vel = Rvector3(cartState[3], cartState[4], cartState[5]);
   Rvector3 R = pos.GetUnitVector();
   Rvector3 V = vel.GetUnitVector();

   // compute cos(90 - beta) as the dot product of the R and V vectors
//    Real rdotv = R*V;
//    mRealValue = rdotv;
   mRealValue = R*V;
   // Changed to use IsEqual() (LOJ: 2010.02.02)
   //if (mRealValue == 0.0)
   if (GmatMathUtil::IsEqual(mRealValue, 0.0))
      mRealValue = 1.0e-40;

   return true;
}
Beispiel #5
0
//------------------------------------------------------------------------------
bool Apoapsis::Evaluate()
{
   if (mOrigin == NULL)
      OrbitData::InitializeRefObjects();
   
   Rvector6 cartState = OrbitData::GetRelativeCartState(mOrigin);
   
   if (cartState == Rvector6::RVECTOR6_UNDEFINED)
      return false;
   
   // compute position and velocity unit vectors
   Rvector3 pos = Rvector3(cartState[0], cartState[1], cartState[2]);
   Rvector3 vel = Rvector3(cartState[3], cartState[4], cartState[5]);
   Rvector3 R = pos.GetUnitVector();
   Rvector3 V = vel.GetUnitVector();
   
   // compute cos(90 - beta) as the dot product of the R and V vectors
   Real rdotv = R*V;
   mRealValue = rdotv;
   if (mRealValue == 0.0)
      mRealValue = -1.0e-40;
   
   //MessageInterface::ShowMessage(wxT("Apoapsis::Evaluate() r=%f,%f,%f, v=%f,%f,%f, r.v=%f\n"),
   //                              R[0], R[1], R[2], V[0], V[1], V[2], rdotv);
   return true;
}
Beispiel #6
0
//---------------------------------------------------------------------------
// Real Ionosphere::BendingAngle()
//---------------------------------------------------------------------------
Real Ionosphere::BendingAngle()
{
   Rvector3 rangeVec = spacecraftLoc - stationLoc;
   Rvector3 dR = rangeVec / NUM_OF_INTERVALS;
   Rvector3 p1 = stationLoc;
   Rvector3 p2, delta;
   Real n1, n2, dn_drho, de1, de2, integrant;
   Real gammar = 0.0;
   
   //Real beta0 = GmatConstants::PI/2 - acos(rangeVec.GetUnitVector()*p1.GetUnitVector());
   Real beta0 = GmatMathConstants::PI_OVER_TWO - acos(rangeVec.GetUnitVector()*p1.GetUnitVector());
   //MessageInterface::ShowMessage("Elevation angle = %f\n", beta0*180/GmatConstants::PI);
   MessageInterface::ShowMessage("Elevation angle = %f\n", beta0*GmatMathConstants::DEG_PER_RAD);
   Real beta = beta0;
   Real freq = GmatPhysicalConstants::SPEED_OF_LIGHT_VACUUM / waveLength;
   for(int i = 0; i < NUM_OF_INTERVALS; ++i)
   {
      p2 = p1 + dR;
      
      delta = dR/100;
      de1 = ElectronDensity(p1+delta, p1);
      de2 = ElectronDensity(p1+2*delta,p1+delta);
      n1 = 1 - 40.3*de1/(freq*freq);
      n2 = 1 - 40.3*de2/(freq*freq);
      dn_drho = -40.3*(de2 - de1)/ (freq*freq) / (((p1+delta).GetMagnitude() - p1.GetMagnitude())*GmatMathConstants::KM_TO_M);
      integrant = dn_drho/(n1*tan(beta));
      gammar += integrant*(p2.GetMagnitude() - p1.GetMagnitude())*GmatMathConstants::KM_TO_M;
      //MessageInterface::ShowMessage("de1 = %.12lf,  de2 = %.12lf, rho1 = %f,   "
      //"rho2 = %f, integrant = %.12lf, gammar =%.12lf\n",de1, de2, p1.GetMagnitude(),
      //p2.GetMagnitude(), integrant, gammar*180/GmatConstants::PI);
      
      p1 = p2;
      beta = beta0 + gammar;
   }
   
   return gammar;
}
Beispiel #7
0
//------------------------------------------------------------------------------
bool USNTwoWayRange::Evaluate(bool withEvents)
{
   bool retval = false;

   if (!initialized)
      InitializeMeasurement();

   #ifdef DEBUG_RANGE_CALC
      MessageInterface::ShowMessage("Entered USNTwoWayRange::Evaluate()\n");
      MessageInterface::ShowMessage("  ParticipantCount: %d\n",
            participants.size());
   #endif

   if (withEvents == false)
   {
      #ifdef DEBUG_RANGE_CALC
         MessageInterface::ShowMessage("USN 2-Way Range Calculation without "
               "events\n");
      #endif

      #ifdef VIEW_PARTICIPANT_STATES
         DumpParticipantStates("++++++++++++++++++++++++++++++++++++++++++++\n"
               "Evaluating USN 2-Way Range without events");
      #endif

      CalculateRangeVectorInertial();
      Rvector3 outState;

      // Set feasibility off of topocentric horizon, set by the Z value in topo
      // coords
      std::string updateAll = "All";
      UpdateRotationMatrix(currentMeasurement.epoch, updateAll);
      outState = R_o_j2k * rangeVecInertial;
      currentMeasurement.feasibilityValue = outState[2];

      #ifdef CHECK_PARTICIPANT_LOCATIONS
         MessageInterface::ShowMessage("Evaluating without events\n");
         MessageInterface::ShowMessage("Calculating USN 2-Way Range at epoch "
               "%.12lf\n", currentMeasurement.epoch);
         MessageInterface::ShowMessage("   J2K Location of %s, id = '%s':  %s",
               participants[0]->GetName().c_str(),
               currentMeasurement.participantIDs[0].c_str(),
               p1Loc.ToString().c_str());
         MessageInterface::ShowMessage("   J2K Location of %s, id = '%s':  %s",
               participants[1]->GetName().c_str(),
               currentMeasurement.participantIDs[1].c_str(),
               p2Loc.ToString().c_str());
         Rvector3 bfLoc = R_o_j2k * p1Loc;
         MessageInterface::ShowMessage("   BodyFixed Location of %s:  %s",
               participants[0]->GetName().c_str(),
               bfLoc.ToString().c_str());
         bfLoc = R_o_j2k * p2Loc;
         MessageInterface::ShowMessage("   BodyFixed Location of %s:  %s\n",
               participants[1]->GetName().c_str(),
               bfLoc.ToString().c_str());
      #endif

      if (currentMeasurement.feasibilityValue > 0.0)
      {
         currentMeasurement.isFeasible = true;
         currentMeasurement.value[0] = rangeVecInertial.GetMagnitude();
         currentMeasurement.eventCount = 2;

         retval = true;
      }
      else
      {
         currentMeasurement.isFeasible = false;
         currentMeasurement.value[0] = 0.0;
         currentMeasurement.eventCount = 0;
      }

      #ifdef DEBUG_RANGE_CALC
         MessageInterface::ShowMessage("Calculating Range at epoch %.12lf\n",
               currentMeasurement.epoch);
         MessageInterface::ShowMessage("   Location of %s, id = '%s':  %s",
               participants[0]->GetName().c_str(),
               currentMeasurement.participantIDs[0].c_str(),
               p1Loc.ToString().c_str());
         MessageInterface::ShowMessage("   Location of %s, id = '%s':  %s",
               participants[1]->GetName().c_str(),
               currentMeasurement.participantIDs[1].c_str(),
               p2Loc.ToString().c_str());
         MessageInterface::ShowMessage("   Range Vector:  %s\n",
               rangeVecInertial.ToString().c_str());
         MessageInterface::ShowMessage("   R(Groundstation) dot RangeVec =  %lf\n",
               currentMeasurement.feasibilityValue);
         MessageInterface::ShowMessage("   Feasibility:  %s\n",
               (currentMeasurement.isFeasible ? "true" : "false"));
         MessageInterface::ShowMessage("   Range is %.12lf\n",
               currentMeasurement.value[0]);
         MessageInterface::ShowMessage("   EventCount is %d\n",
               currentMeasurement.eventCount);
      #endif

      #ifdef SHOW_RANGE_CALC
         MessageInterface::ShowMessage("Range at epoch %.12lf is ",
               currentMeasurement.epoch);
         if (currentMeasurement.isFeasible)
            MessageInterface::ShowMessage("feasible, value = %.12lf\n",
               currentMeasurement.value[0]);
         else
            MessageInterface::ShowMessage("not feasible\n");
      #endif
   }
   else
   {
      // Calculate the corrected range measurement
      #ifdef DEBUG_RANGE_CALC_WITH_EVENTS
         MessageInterface::ShowMessage("USN 2-Way Range Calculation:\n");
      #endif

      #ifdef VIEW_PARTICIPANT_STATES_WITH_EVENTS
         DumpParticipantStates("********************************************\n"
               "Evaluating USN 2-Way Range with located events");
      #endif

      // 1. Get the range from the down link
      Rvector3 r1, r2;
      r1 = downlinkLeg.GetPosition(participants[0]);
      r2 = downlinkLeg.GetPosition(participants[1]);
      #ifdef DEBUG_RANGE_CALC_WITH_EVENTS
         MessageInterface::ShowMessage("r1 = (%f,  %f,  %f)\n", r1.Get(0), r1.Get(1), r1.Get(2));
         MessageInterface::ShowMessage("r2 = (%f,  %f,  %f)\n", r2.Get(0), r2.Get(1), r2.Get(2));
      #endif
      Rvector3 downlinkVector = r2 - r1;		// rVector = r2 - r1;
      downlinkRange = downlinkVector.GetMagnitude();
      #ifdef DEBUG_RANGE_CALC_WITH_EVENTS
         MessageInterface::ShowMessage("   Downlink Range = r2-r1:  %.12lf km\n",
               downlinkRange);
      #endif

	   // 2. Calculate down link range rate:
      Rvector3 p1V = downlinkLeg.GetVelocity(participants[0]);
      Rvector3 p2V = downlinkLeg.GetVelocity(participants[1]);
      #ifdef DEBUG_RANGE_CALC_WITH_EVENTS
         MessageInterface::ShowMessage("p1V = (%f,  %f,  %f)\n", p1V.Get(0), p1V.Get(1), p1V.Get(2));
         MessageInterface::ShowMessage("p2V = (%f,  %f,  %f)\n", p2V.Get(0), p2V.Get(1), p2V.Get(2));
      #endif
      // @todo Relative origin velocities need to be subtracted when the origins
      // differ; check and fix that part using r12_j2k_vel here.  It's not yet
      // incorporated because we need to handle the different epochs for the
      // bodies, and we ought to do this part in barycentric coordinates
      Rvector downRRateVec = p2V - p1V /* - r12_j2k_vel*/;
      Rvector3 rangeUnit = downlinkVector.GetUnitVector();
      downlinkRangeRate = downRRateVec * rangeUnit;
      #ifdef DEBUG_RANGE_CALC_WITH_EVENTS
         MessageInterface::ShowMessage("   Downlink Range Rate:  %.12lf km/s\n",
               downlinkRangeRate);
      #endif

      // 3. Get the transponder delay
      targetDelay = GetDelay(1,0);
      #ifdef DEBUG_RANGE_CALC_WITH_EVENTS
         MessageInterface::ShowMessage(
               "    USN Transponder delay for %s = %.12lf s\n",
               participants[1]->GetName().c_str(), targetDelay);
      #endif

      // 4. Get the range from the uplink
      Rvector3 r3, r4;
      r3 = uplinkLeg.GetPosition(participants[0]);
      r4 = uplinkLeg.GetPosition(participants[1]);
      #ifdef DEBUG_RANGE_CALC_WITH_EVENTS
         MessageInterface::ShowMessage("r3 = (%f,  %f,  %f)\n", r3.Get(0), r3.Get(1), r3.Get(2));
         MessageInterface::ShowMessage("r4 = (%f,  %f,  %f)\n", r4.Get(0), r4.Get(1), r4.Get(2));
      #endif
      Rvector3 uplinkVector = r4 - r3;
      uplinkRange = uplinkVector.GetMagnitude();
      #ifdef DEBUG_RANGE_CALC_WITH_EVENTS
         MessageInterface::ShowMessage("   Uplink Range = r4-r3:  %.12lf km\n",
               uplinkRange);
      #endif

	   // 5. Calculate up link range rate
      Rvector3 p3V = uplinkLeg.GetVelocity(participants[0]);
      Rvector3 p4V = uplinkLeg.GetVelocity(participants[1]);
      #ifdef DEBUG_RANGE_CALC_WITH_EVENTS
         MessageInterface::ShowMessage("p3V = (%f,  %f,  %f)\n", p3V.Get(0), p3V.Get(1), p3V.Get(2));
         MessageInterface::ShowMessage("p4V = (%f,  %f,  %f)\n", p4V.Get(0), p4V.Get(1), p4V.Get(2));
      #endif
      // @todo Relative origin velocities need to be subtracted when the origins
      // differ; check and fix that part using r12_j2k_vel here.  It's not yet
      // incorporated because we need to handle the different epochs for the
      // bodies, and we ought to do this part in barycentric coordinates
      Rvector upRRateVec = p4V - p3V /* - r12_j2k_vel*/ ;
      rangeUnit = uplinkVector.GetUnitVector();
      uplinkRangeRate = upRRateVec * rangeUnit;
      #ifdef DEBUG_RANGE_CALC_WITH_EVENTS
         MessageInterface::ShowMessage("   Uplink Range Rate:  %.12lf km/s\n",
               uplinkRangeRate);
      #endif

      // 5.1. Target range rate: Do we need this as well?
      targetRangeRate = (downlinkRangeRate + uplinkRangeRate) / 2.0;
	   #ifdef DEBUG_RANGE_CALC_WITH_EVENTS
         MessageInterface::ShowMessage("   Target Range Rate:  %.12lf km/s\n",
                targetRangeRate);
		#endif
      

	   // 6. Get sensors used in USN 2-ways range
	   ObjectArray objList1;
	   ObjectArray objList2;
	   ObjectArray objList3;
	   //			objList1 := all transmitters in participantHardware list
	   //			objList2 := all receivers in participantHardware list
	   //			objList3 := all transponders in participantHardware list
	   if (participantHardware.empty()||
	   		((!participantHardware.empty())&&
	   		  participantHardware[0].empty()&&
	   		  participantHardware[1].empty()
	   		)
	   	)
	   {
	   	// DO NOT LEAVE THIS TYPE OF MESSAGE IN THE CODE WITHOUT #ifdef WRAPPERS!!!
         //MessageInterface::ShowMessage("    Ideal measurement (no hardware delay and no media correction involve):\n");
		   Real realRange = (uplinkRange + downlinkRange)/2;
		   #ifdef DEBUG_RANGE_CALC_WITH_EVENTS
				MessageInterface::ShowMessage("   Range = %.12lf km\n", realRange);
			#endif

	   	// Set value for currentMeasurement
		   currentMeasurement.value[0] = realRange;
	      currentMeasurement.isFeasible = true;

	      return true;
	   }

	   for(std::vector<Hardware*>::iterator hw = this->participantHardware[0].begin();
	   		hw != this->participantHardware[0].end(); ++hw)
	   {
	   	if ((*hw) != NULL)
	   	{
	   		if ((*hw)->GetTypeName() == "Transmitter")
	   			objList1.push_back(*hw);
	   		if ((*hw)->GetTypeName() == "Receiver")
	   			objList2.push_back(*hw);
	   	}
	   	else
	   		MessageInterface::ShowMessage(" sensor = NULL\n");
	   }

	   for(std::vector<Hardware*>::iterator hw = this->participantHardware[1].begin();
	   		hw != this->participantHardware[1].end(); ++hw)
	   {
	   	if ((*hw) != NULL)
	   	{
	   		if ((*hw)->GetTypeName() == "Transponder")
	   			objList3.push_back(*hw);
	   	}
	   	else
	   		MessageInterface::ShowMessage(" sensor = NULL\n");
	   }

	   if (objList1.size() != 1)
	   {
	   	MessageInterface::ShowMessage("The first participant does not have only 1 transmitter to send signal.\n");
	      throw new MeasurementException("The first participant does not have only 1 transmitter to send signal.\n");
	   }
	   if (objList2.size() != 1)
	   {
	   	MessageInterface::ShowMessage("The first participant does not have only 1 receiver to receive signal.\n");
	      throw new MeasurementException("The first participant does not have only 1 receiver to receive signal.\n");
	   }
	   if (objList3.size() != 1)
	   {
	   	MessageInterface::ShowMessage("The second participant does not have only 1 transponder to transpond signal.\n");
  			throw new MeasurementException("The second participant does not have only 1 transponder to transpond signal.\n");
	   }

	   Transmitter* 	gsTransmitter 	= (Transmitter*)objList1[0];
	   Receiver* 		gsReceiver 		= (Receiver*)objList2[0];
	   Transponder* 	scTransponder 	= (Transponder*)objList3[0];
	   if (gsTransmitter == NULL)
	   {
	   	MessageInterface::ShowMessage("Transmitter is NULL object.\n");
	   	throw new GmatBaseException("Transmitter is NULL object.\n");
	   }
	   if (gsReceiver == NULL)
	   {
	   	MessageInterface::ShowMessage("Receiver is NULL object.\n");
	   	throw new GmatBaseException("Receiver is NULL object.\n");
	   }
	   if (scTransponder == NULL)
	   {
	   	MessageInterface::ShowMessage("Transponder is NULL object.\n");
	   	throw new GmatBaseException("Transponder is NULL object.\n");
	   }

		#ifdef DEBUG_RANGE_CALC_WITH_EVENTS
			MessageInterface::ShowMessage("   List of sensors: %s, %s, %s\n",
					gsTransmitter->GetName().c_str(), gsReceiver->GetName().c_str(),
					scTransponder->GetName().c_str());
		#endif


	   // 7. Get frequency from transmitter of ground station (participants[0])
	   Signal* uplinkSignal = gsTransmitter->GetSignal();
	   Real uplinkFreq = uplinkSignal->GetValue();

		#ifdef DEBUG_RANGE_CALC_WITH_EVENTS
			MessageInterface::ShowMessage("   UpLink signal frequency = %.12lf MHz\n", uplinkFreq);
		#endif

	   // 8. Calculate media correction for uplink leg:
      #ifdef DEBUG_RANGE_CALC_WITH_EVENTS
         MessageInterface::ShowMessage("      Media correction for uplink leg\n");
      #endif
      Real roundTripTime = ((uplinkRange + downlinkRange)*GmatMathConstants::KM_TO_M/GmatPhysicalConstants::SPEED_OF_LIGHT_VACUUM)/GmatTimeConstants::SECS_PER_DAY;
      // DO NOT LEAVE THIS TYPE OF MESSAGE IN THE CODE WITHOUT #ifdef WRAPPERS!!!
      //MessageInterface::ShowMessage("Round trip time = %.12lf\n", roundTripTime);
      RealArray uplinkCorrection = CalculateMediaCorrection(uplinkFreq, r1, r2, currentMeasurement.epoch - roundTripTime);
      Real uplinkRangeCorrection = uplinkCorrection[0]/GmatMathConstants::KM_TO_M;
      Real uplinkRealRange = uplinkRange + uplinkRangeCorrection;
		#ifdef DEBUG_RANGE_CALC_WITH_EVENTS
			MessageInterface::ShowMessage("      Uplink range correction = %.12lf km\n",uplinkRangeCorrection);
			MessageInterface::ShowMessage("      Uplink real range = %.12lf km\n",uplinkRealRange);
		#endif

		// 9. Doppler shift the frequency from the transmitter using uplinkRangeRate:
	   Real uplinkDSFreq = (1 - uplinkRangeRate*GmatMathConstants::KM_TO_M/GmatPhysicalConstants::SPEED_OF_LIGHT_VACUUM)*uplinkFreq;

		#ifdef DEBUG_RANGE_CALC_WITH_EVENTS
			MessageInterface::ShowMessage("    Uplink Doppler shift frequency = %.12lf MHz\n", uplinkDSFreq);
		#endif

	   // 10.Set frequency for the input signal of transponder
	   Signal* inputSignal = scTransponder->GetSignal(0);
	   inputSignal->SetValue(uplinkDSFreq);
	   scTransponder->SetSignal(inputSignal, 0);

	   // 11. Check the transponder feasibility to receive the input signal:
	   if (scTransponder->IsFeasible(0) == false)
	   {
	   	 currentMeasurement.isFeasible = false;
	   	 currentMeasurement.value[0] = 0;
	   	 MessageInterface::ShowMessage("The transponder is unfeasible to receive uplink signal.\n");
	   	 throw new GmatBaseException("The transponder is unfeasible to receive uplink signal.\n");
	   }

	   // 12. Get frequency of transponder output signal
	   Signal* outputSignal = scTransponder->GetSignal(1);
	   Real downlinkFreq = outputSignal->GetValue();

		#ifdef DEBUG_RANGE_CALC_WITH_EVENTS
			MessageInterface::ShowMessage("    Downlink frequency = %.12lf Mhz\n", downlinkFreq);
		#endif

	   // 13. Doppler shift the transponder output frequency by the downlinkRangeRate:
	   Real downlinkDSFreq = (1 - downlinkRangeRate*GmatMathConstants::KM_TO_M/GmatPhysicalConstants::SPEED_OF_LIGHT_VACUUM)*downlinkFreq;

	   #ifdef DEBUG_RANGE_CALC_WITH_EVENTS
			MessageInterface::ShowMessage("    Downlink Doppler shift frequency = %.12lf MHz\n", downlinkDSFreq);
		#endif

	   // 14. Set frequency on receiver
	   Signal* downlinkSignal = gsReceiver->GetSignal();
	   downlinkSignal->SetValue(downlinkDSFreq);

	   // 15. Check the receiver feasibility to receive the downlink signal
	   if (gsReceiver->IsFeasible() == false)
	   {
	   	 currentMeasurement.isFeasible = false;
	   	 currentMeasurement.value[0] = 0;
	   	 throw new MeasurementException("The receiver is unfeasible to receive downlink signal.\n");
	   }

	   // 16. Calculate media correction for downlink leg:
	   #ifdef DEBUG_RANGE_CALC_WITH_EVENTS
	      MessageInterface::ShowMessage("      Media correction for downlink leg\n");
	   #endif
	   RealArray downlinkCorrection = CalculateMediaCorrection(downlinkDSFreq, r3, r4, currentMeasurement.epoch);
	   Real downlinkRangeCorrection = downlinkCorrection[0]/GmatMathConstants::KM_TO_M;
	   Real downlinkRealRange = downlinkRange + downlinkRangeCorrection;
		#ifdef DEBUG_RANGE_CALC_WITH_EVENTS
			MessageInterface::ShowMessage("      Downlink range correction = %.12lf km\n",downlinkRangeCorrection);
			MessageInterface::ShowMessage("      Downlink real range = %.12lf km\n",downlinkRealRange);
		#endif


	   // 17. Calculate uplink time and down link time: (Is it needed???)
	   uplinkTime   = uplinkRealRange*GmatMathConstants::KM_TO_M / GmatPhysicalConstants::SPEED_OF_LIGHT_VACUUM;
	   downlinkTime = downlinkRealRange*GmatMathConstants::KM_TO_M / GmatPhysicalConstants::SPEED_OF_LIGHT_VACUUM;

		#ifdef DEBUG_RANGE_CALC_WITH_EVENTS
			MessageInterface::ShowMessage("    Uplink time = %.12lf s\n",uplinkTime);
			MessageInterface::ShowMessage("    Downlink time = %.12lf s\n",downlinkTime);
		#endif

	   // 18. Calculate real range
	   Real realRange = uplinkRealRange + downlinkRealRange +
	   		targetDelay*GmatPhysicalConstants::SPEED_OF_LIGHT_VACUUM / GmatMathConstants::KM_TO_M;
	   
      #ifdef DEBUG_RANGE_CALC_WITH_EVENTS
         MessageInterface::ShowMessage("   Calculated real range = %.12lf km\n", realRange/2);
      #endif

	   // 19. Set value for currentMeasurement
	   currentMeasurement.value[0] = realRange / 2.0;
      currentMeasurement.isFeasible = true;


      #ifdef PRELIMINARY_DERIVATIVE_CHECK
         MessageInterface::ShowMessage("Participants:\n ");
         for (UnsignedInt i = 0; i < participants.size(); ++i)
            MessageInterface::ShowMessage("   %d: %s of type %s\n", i,
                  participants[i]->GetName().c_str(),
                  participants[i]->GetTypeName().c_str());

         Integer id = participants[1]->GetType() * 250 +
               participants[1]->GetParameterID("CartesianX");
         CalculateMeasurementDerivatives(participants[1], id);
      #endif

      retval = true;
   }

   return retval;
}
Beispiel #8
0
//---------------------------------------------------------------------------
void ObjectReferencedAxes::CalculateRotationMatrix(const A1Mjd &atEpoch,
                                                   bool forceComputation)
{
   if (!primary)
      throw CoordinateSystemException("Primary \"" + primaryName +
         "\" is not yet set in object referenced coordinate system!");

   if (!secondary)
      throw CoordinateSystemException("Secondary \"" + secondaryName +
         "\" is not yet set in object referenced coordinate system!");

   
   if ((xAxis == yAxis) || (xAxis == zAxis) || (yAxis == zAxis))
   {
      CoordinateSystemException cse;
      cse.SetDetails("For object referenced axes, axes are improperly "
                     "defined.\nXAxis = '%s', YAxis = '%s', ZAxis = '%s'",
                     xAxis.c_str(), yAxis.c_str(), zAxis.c_str());
      throw cse;
   }
   
   if ((xAxis != "") && (yAxis != "") && (zAxis != ""))
   {
      CoordinateSystemException cse;
      cse.SetDetails("For object referenced axes, too many axes are defined.\n"
                     "XAxis = '%s', YAxis = '%s', ZAxis = '%s'",
                     xAxis.c_str(), yAxis.c_str(), zAxis.c_str());
      throw cse;
   }
   
   SpacePoint *useAsSecondary = secondary;
//   if (!useAsSecondary)  useAsSecondary = origin;
   Rvector6 rv     = useAsSecondary->GetMJ2000State(atEpoch) -
                     primary->GetMJ2000State(atEpoch);
   #ifdef DEBUG_ROT_MATRIX
      if (visitCount == 0)
      {
         MessageInterface::ShowMessage(" ------------ rv Primary (%s) to Secondary (%s) = %s\n",
               primary->GetName().c_str(), secondary->GetName().c_str(), rv.ToString().c_str());
         visitCount++;
      }
   #endif

   #ifdef DEBUG_ROT_MATRIX
      if (visitCount == 0)
      {
         std::stringstream ss;
         ss.precision(30);
         ss << " ----------------- rv Earth to Moon (truncated)    = "
              << rv << std::endl;

         MessageInterface::ShowMessage("%s\n", ss.str().c_str());
         visitCount++;
      }
   #endif

   Rvector3 a     =  useAsSecondary->GetMJ2000Acceleration(atEpoch) -
                     primary->GetMJ2000Acceleration(atEpoch);
   
   Rvector3 r      = rv.GetR();
   Rvector3 v      = rv.GetV();
   Rvector3 n     =  Cross(r,v);
   Rvector3 rUnit = r.GetUnitVector();
   Rvector3 vUnit = v.GetUnitVector();
   Rvector3 nUnit = n.GetUnitVector();
   Real     rMag  = r.GetMagnitude();
   Real     vMag  = v.GetMagnitude();
   Real     nMag  = n.GetMagnitude();
   // check for divide-by-zero
   if ((GmatMathUtil::IsEqual(rMag, MAGNITUDE_TOL)) || (GmatMathUtil::IsEqual(vMag, MAGNITUDE_TOL)) || (GmatMathUtil::IsEqual(nMag, MAGNITUDE_TOL)))
   {
      std::string errmsg = "Object referenced axis system named \"";
      errmsg += coordName + "\" is undefined because at least one axis is near zero in length.\n";
      throw CoordinateSystemException(errmsg);
   }

   Rvector3 rDot  = (v / rMag) - (rUnit / rMag) * (rUnit * v);
   Rvector3 vDot  = (a / vMag) - (vUnit / vMag) * (vUnit * a);
   Rvector3 nDot = (Cross(r,a) / nMag) - (nUnit / nMag) * (Cross(r,a) * nUnit);
   Rvector3 xUnit, yUnit, zUnit, xDot, yDot, zDot;
   bool     xUsed = true, yUsed = true, zUsed = true;


   // determine the x-axis
   if ((xAxis == "R") || (xAxis == "r"))
   {
      xUnit = rUnit;
      xDot  = rDot;
   }
   else if ((xAxis == "-R") || (xAxis == "-r"))
   {
      xUnit = -rUnit;
      xDot  = -rDot;
   }
   else if ((xAxis == "V") || (xAxis == "v"))
   {
      xUnit = vUnit;
      xDot  = vDot;
   }
   else if ((xAxis == "-V") || (xAxis == "-v"))
   {
      xUnit = -vUnit;
      xDot  = -vDot;
   }
   else if ((xAxis == "N") || (xAxis == "n"))
   {
      xUnit = nUnit;
      xDot  = nDot;
   }
   else if ((xAxis == "-N") || (xAxis == "-n"))
   {
      xUnit = -nUnit;
      xDot  = -nDot;
   }
   else
   {
      xUsed = false;
   }
   // determine the y-axis
   if ((yAxis == "R") || (yAxis == "r"))
   {
      yUnit = rUnit;
      yDot  = rDot;
   }
   else if ((yAxis == "-R") || (yAxis == "-r"))
   {
      yUnit = -rUnit;
      yDot  = -rDot;
   }
   else if ((yAxis == "V") || (yAxis == "v"))
   {
      yUnit = vUnit;
      yDot  = vDot;
   }
   else if ((yAxis == "-V") || (yAxis == "-v"))
   {
      yUnit = -vUnit;
      yDot  = -vDot;
   }
   else if ((yAxis == "N") || (yAxis == "n"))
   {
      yUnit = nUnit;
      yDot  = nDot;
   }
   else if ((yAxis == "-N") || (yAxis == "-n"))
   {
      yUnit = -nUnit;
      yDot  = -nDot;
   }
   else
   {
      yUsed = false;
   }
   // determine the z-axis
   if ((zAxis == "R") || (zAxis == "r"))
   {
      zUnit = rUnit;
      zDot  = rDot;
   }
   else if ((zAxis == "-R") || (zAxis == "-r"))
   {
      zUnit = -rUnit;
      zDot  = -rDot;
   }
   else if ((zAxis == "V") || (zAxis == "v"))
   {
      zUnit = vUnit;
      zDot  = vDot;
   }
   else if ((zAxis == "-V") || (zAxis == "-v"))
   {
      zUnit = -vUnit;
      zDot  = -vDot;
   }
   else if ((zAxis == "N") || (zAxis == "n"))
   {
      zUnit = nUnit;
      zDot  = nDot;
   }
   else if ((zAxis == "-N") || (zAxis == "-n"))
   {
      zUnit = -nUnit;
      zDot  = -nDot;
   }
   else
   {
      zUsed = false;
   }
   // determine the third axis
   if (xUsed && yUsed && !zUsed)
   {
      zUnit = Cross(xUnit, yUnit);
      zDot  = Cross(xDot, yUnit) + Cross(xUnit, yDot);
   }
   else if (xUsed && zUsed && !yUsed)
   {
      yUnit = Cross(zUnit,xUnit);
      yDot  = Cross(zDot, xUnit) + Cross(zUnit, xDot);
   }
   else if (yUsed && zUsed && !xUsed)
   {
      xUnit = Cross(yUnit,zUnit);
      xDot  = Cross(yDot, zUnit) + Cross(yUnit, zDot);
   }
   else
   {
      throw CoordinateSystemException(
            "Object referenced axes are improperly defined.");
   }
   // Compute the rotation matrix
   rotMatrix(0,0) = xUnit(0);
   rotMatrix(0,1) = yUnit(0);
   rotMatrix(0,2) = zUnit(0);
   rotMatrix(1,0) = xUnit(1);
   rotMatrix(1,1) = yUnit(1);
   rotMatrix(1,2) = zUnit(1);
   rotMatrix(2,0) = xUnit(2);
   rotMatrix(2,1) = yUnit(2);
   rotMatrix(2,2) = zUnit(2);

   // Compute the rotation derivative matrix
   rotDotMatrix(0,0) = xDot(0);
   rotDotMatrix(0,1) = yDot(0);
   rotDotMatrix(0,2) = zDot(0);
   rotDotMatrix(1,0) = xDot(1);
   rotDotMatrix(1,1) = yDot(1);
   rotDotMatrix(1,2) = zDot(1);
   rotDotMatrix(2,0) = xDot(2);
   rotDotMatrix(2,1) = yDot(2);
   rotDotMatrix(2,2) = zDot(2);

   #ifdef DEBUG_ROT_MATRIX
      MessageInterface::ShowMessage
         ("rotMatrix=%s\n", rotMatrix.ToString().c_str());

      std::stringstream ss;

      ss.setf(std::ios::fixed);
      ss.precision(30);
      ss << " ----------------- rotMatrix    = " << rotMatrix << std::endl;
      ss.setf(std::ios::scientific);
      ss << " ----------------- rotDotMatrix = " << rotDotMatrix << std::endl;

      MessageInterface::ShowMessage("%s\n", ss.str().c_str());
   #endif

   if (!rotMatrix.IsOrthonormal(ORTHONORMAL_TOL))
   {
      std::stringstream errmsg("");
      errmsg << "*** WARNING*** Object referenced axis system \"" << coordName;
      errmsg << "\" has a non-orthogonal rotation matrix. " << std::endl;
   }
}
Beispiel #9
0
//------------------------------------------------------------------------------
bool DSNTwoWayRange::Evaluate(bool withEvents)
{
   bool retval = false;

   if (!initialized)
      InitializeMeasurement();

   #ifdef DEBUG_RANGE_CALC
      MessageInterface::ShowMessage("Entered DSNTwoWayRange::Evaluate(%s)\n",
            (withEvents ? "true" : "false"));
      MessageInterface::ShowMessage("  ParticipantCount: %d\n",
            participants.size());
   #endif

   if (withEvents == false)
   {
      #ifdef DEBUG_RANGE_CALC
         MessageInterface::ShowMessage("DSN 2-Way Range Calculation without "
               "events\n");
      #endif

      #ifdef VIEW_PARTICIPANT_STATES
         DumpParticipantStates("++++++++++++++++++++++++++++++++++++++++++++\n"
               "Evaluating DSN 2-Way Range without events");
      #endif

      CalculateRangeVectorInertial();
      Rvector3 outState;

      // Set feasibility off of topocentric horizon, set by the Z value in topo
      // coords
      std::string updateAll = "All";
      UpdateRotationMatrix(currentMeasurement.epoch, updateAll);
      outState = R_o_j2k * rangeVecInertial;
      currentMeasurement.feasibilityValue = outState[2];

      #ifdef CHECK_PARTICIPANT_LOCATIONS
         MessageInterface::ShowMessage("Evaluating without events\n");
         MessageInterface::ShowMessage("Calculating DSN 2-Way Range at epoch "
               "%.12lf\n", currentMeasurement.epoch);
         MessageInterface::ShowMessage("   J2K Location of %s, id = '%s':  %s",
               participants[0]->GetName().c_str(),
               currentMeasurement.participantIDs[0].c_str(),
               p1Loc.ToString().c_str());
         MessageInterface::ShowMessage("   J2K Location of %s, id = '%s':  %s",
               participants[1]->GetName().c_str(),
               currentMeasurement.participantIDs[1].c_str(),
               p2Loc.ToString().c_str());
         Rvector3 bfLoc = R_o_j2k * p1Loc;
         MessageInterface::ShowMessage("   BodyFixed Location of %s:  %s",
               participants[0]->GetName().c_str(),
               bfLoc.ToString().c_str());
         bfLoc = R_o_j2k * p2Loc;
         MessageInterface::ShowMessage("   BodyFixed Location of %s:  %s\n",
               participants[1]->GetName().c_str(),
               bfLoc.ToString().c_str());
      #endif

      if (currentMeasurement.feasibilityValue > 0.0)
      {
         currentMeasurement.isFeasible = true;
         currentMeasurement.value[0] = rangeVecInertial.GetMagnitude();
         currentMeasurement.eventCount = 2;

         SetHardwareDelays(false);

         retval = true;
      }
      else
      {
         currentMeasurement.isFeasible = false;
         currentMeasurement.value[0] = 0.0;
         currentMeasurement.eventCount = 0;
      }

      #ifdef DEBUG_RANGE_CALC
         MessageInterface::ShowMessage("Calculating Range at epoch %.12lf\n",
               currentMeasurement.epoch);
         MessageInterface::ShowMessage("   Location of %s, id = '%s':  %s",
               participants[0]->GetName().c_str(),
               currentMeasurement.participantIDs[0].c_str(),
               p1Loc.ToString().c_str());
         MessageInterface::ShowMessage("   Location of %s, id = '%s':  %s",
               participants[1]->GetName().c_str(),
               currentMeasurement.participantIDs[1].c_str(),
               p2Loc.ToString().c_str());
         MessageInterface::ShowMessage("   Range Vector:  %s\n",
               rangeVecInertial.ToString().c_str());
         MessageInterface::ShowMessage("   R(Groundstation) dot RangeVec =  %lf\n",
               currentMeasurement.feasibilityValue);
         MessageInterface::ShowMessage("   Feasibility:  %s\n",
               (currentMeasurement.isFeasible ? "true" : "false"));
         MessageInterface::ShowMessage("   Range is %.12lf\n",
               currentMeasurement.value[0]);
         MessageInterface::ShowMessage("   EventCount is %d\n",
               currentMeasurement.eventCount);
      #endif

      #ifdef SHOW_RANGE_CALC
         MessageInterface::ShowMessage("Range at epoch %.12lf is ",
               currentMeasurement.epoch);
         if (currentMeasurement.isFeasible)
            MessageInterface::ShowMessage("feasible, value = %.12lf\n",
               currentMeasurement.value[0]);
         else
            MessageInterface::ShowMessage("not feasible\n");
      #endif
   }
   else
   {
      // Calculate the corrected range measurement
      #ifdef DEBUG_RANGE_CALC_WITH_EVENTS
         MessageInterface::ShowMessage("\n\n DSN 2-Way Range Calculation:\n");
      #endif

      #ifdef VIEW_PARTICIPANT_STATES_WITH_EVENTS
         DumpParticipantStates("********************************************\n"
               "Evaluating DSN 2-Way Range with located events");
      #endif

      // 1. Get the range from the down link
      Rvector3 r1, r2;
	  Real t1, t2;
      r1 = downlinkLeg.GetPosition(participants[0]);
      r2 = downlinkLeg.GetPosition(participants[1]);
	  t1 = downlinkLeg.GetEventData((GmatBase*) participants[0]).epoch;
	  t2 = downlinkLeg.GetEventData((GmatBase*) participants[1]).epoch;
	  Rmatrix33 mt = downlinkLeg.GetEventData((GmatBase*) participants[0]).rInertial2obj.Transpose();
      #ifdef DEBUG_RANGE_CALC_WITH_EVENTS
	     MessageInterface::ShowMessage("1. Get downlink leg range:\n");
         MessageInterface::ShowMessage("   Ground station position in FK5: r1 = (%f, %f, %f)km  at epoch = %18.12lf\n", r1.Get(0), r1.Get(1), r1.Get(2), t1);
         MessageInterface::ShowMessage("   Spacecraft position in FK5    : r2 = (%f, %f, %f)km  at epoch = %18.12lf\n", r2.Get(0), r2.Get(1), r2.Get(2), t2);
		 MessageInterface::ShowMessage("   Transformation matrix from Earth fixed coordinate system to FK5 coordinate system at epoch = %18.12lf:\n", t1);
		 MessageInterface::ShowMessage("                %18.12lf  %18.12lf  %18.12lf\n", mt(0,0), mt(0,1), mt(0,2));
		 MessageInterface::ShowMessage("                %18.12lf  %18.12lf  %18.12lf\n", mt(1,0), mt(1,1), mt(1,2));
		 MessageInterface::ShowMessage("                %18.12lf  %18.12lf  %18.12lf\n", mt(2,0), mt(2,1), mt(2,2));
      #endif
      Rvector3 downlinkVector = r2 - r1;		// rVector = r2 - r1;
      downlinkRange = downlinkVector.GetMagnitude();
      #ifdef DEBUG_RANGE_CALC_WITH_EVENTS
         MessageInterface::ShowMessage("   Downlink Range = r2-r1:  %.12lf km\n",
               downlinkRange);
      #endif


 	   // 2. Calculate down link range rate:
      Rvector3 p1V = downlinkLeg.GetVelocity(participants[0]);
      Rvector3 p2V = downlinkLeg.GetVelocity(participants[1]);
      #ifdef DEBUG_RANGE_CALC_WITH_EVENTS
	     MessageInterface::ShowMessage("2. Get downlink leg range rate:\n");
         MessageInterface::ShowMessage("   Ground station velocity in FK5: p1V = (%f, %f, %f)km/s\n", p1V.Get(0), p1V.Get(1), p1V.Get(2));
         MessageInterface::ShowMessage("   Spacecraft velocity in FK5    : p2V = (%f, %f, %f)km/s\n", p2V.Get(0), p2V.Get(1), p2V.Get(2));
      #endif
      // @todo Relative origin velocities need to be subtracted when the origins
      // differ; check and fix that part using r12_j2k_vel here.  It's not yet
      // incorporated because we need to handle the different epochs for the
      // bodies, and we ought to do this part in barycentric coordinates
      Rvector downRRateVec = p2V - p1V /* - r12_j2k_vel*/;
      Rvector3 rangeUnit = downlinkVector.GetUnitVector();
      downlinkRangeRate = downRRateVec * rangeUnit;
      #ifdef DEBUG_RANGE_CALC_WITH_EVENTS
         MessageInterface::ShowMessage("   Downlink Range Rate:  %.12lf km/s\n",
               downlinkRangeRate);
      #endif


      // 3. Get the range from the uplink
      Rvector3 r3, r4;
	  Real t3, t4;
      r3 = uplinkLeg.GetPosition(participants[0]);
      r4 = uplinkLeg.GetPosition(participants[1]);
	  t3 = uplinkLeg.GetEventData((GmatBase*) participants[0]).epoch;
	  t4 = uplinkLeg.GetEventData((GmatBase*) participants[1]).epoch;
	  Rmatrix33 mt1 = uplinkLeg.GetEventData((GmatBase*) participants[0]).rInertial2obj.Transpose();
      #ifdef DEBUG_RANGE_CALC_WITH_EVENTS
	     MessageInterface::ShowMessage("3. Get uplink leg range:\n");
         MessageInterface::ShowMessage("   Spacecraft position in FK5    : r4 = (%f, %f, %f)km   at epoch = %18.12lf\n", r4.Get(0), r4.Get(1), r4.Get(2), t4);
         MessageInterface::ShowMessage("   Ground station position in FK5: r3 = (%f, %f, %f)km   at epoch = %18.12lf\n", r3.Get(0), r3.Get(1), r3.Get(2), t3);
		 MessageInterface::ShowMessage("   Transformation matrix from Earth fixed coordinate system to FK5 coordinate system at epoch = %18.12lf:\n", t3);
		 MessageInterface::ShowMessage("                %18.12lf  %18.12lf  %18.12lf\n", mt1(0,0), mt1(0,1), mt1(0,2));
		 MessageInterface::ShowMessage("                %18.12lf  %18.12lf  %18.12lf\n", mt1(1,0), mt1(1,1), mt1(1,2));
		 MessageInterface::ShowMessage("                %18.12lf  %18.12lf  %18.12lf\n", mt1(2,0), mt1(2,1), mt1(2,2));
      #endif
      Rvector3 uplinkVector = r4 - r3;
      uplinkRange = uplinkVector.GetMagnitude();
      #ifdef DEBUG_RANGE_CALC_WITH_EVENTS
         MessageInterface::ShowMessage("   Uplink Range = r4-r3:  %.12lf km\n",
               uplinkRange);
      #endif


   	// 4. Calculate up link range rate
      Rvector3 p3V = uplinkLeg.GetVelocity(participants[0]);
      Rvector3 p4V = uplinkLeg.GetVelocity(participants[1]);
      #ifdef DEBUG_RANGE_CALC_WITH_EVENTS
	     MessageInterface::ShowMessage("4. Get uplink leg range rate:\n");
         MessageInterface::ShowMessage("   Ground station velocity in FK5: p3V = (%f, %f, %f)km/s\n", p3V.Get(0), p3V.Get(1), p3V.Get(2));
         MessageInterface::ShowMessage("   Spacecraft velocity in FK5    : p4V = (%f, %f, %f)km/s\n", p4V.Get(0), p4V.Get(1), p4V.Get(2));
      #endif
      // @todo Relative origin velocities need to be subtracted when the origins
      // differ; check and fix that part using r12_j2k_vel here.  It's not yet
      // incorporated because we need to handle the different epochs for the
      // bodies, and we ought to do this part in barycentric coordinates
      Rvector upRRateVec = p4V - p3V /* - r12_j2k_vel*/ ;
      rangeUnit = uplinkVector.GetUnitVector();
      uplinkRangeRate = upRRateVec * rangeUnit;
      #ifdef DEBUG_RANGE_CALC_WITH_EVENTS
         MessageInterface::ShowMessage("   Uplink Range Rate:  %.12lf km/s\n",
               uplinkRangeRate);
      #endif

      // 4.1. Target range rate: Do we need this as well?
      targetRangeRate = (downlinkRangeRate + uplinkRangeRate) / 2.0;

		#ifdef DEBUG_RANGE_CALC_WITH_EVENTS
			MessageInterface::ShowMessage("   Target Range Rate:  %.12lf km/s\n",
						targetRangeRate);
		#endif


		// 5. Get sensors used in DSN 2-ways range
	   if (participantHardware.empty()||
	   		((!participantHardware.empty())&&
	   		  participantHardware[0].empty()&&
	   		  participantHardware[1].empty()
	   		)
	   	)
	   {
         // DO NOT LEAVE THIS RAW IN A SOURCE FILE!!!
	   	// MessageInterface::ShowMessage("    Ideal measurement (no hardware delay and no media correction involve):\n");

		   // Calculate uplink time and down link time: (Is it needed???)
		   uplinkTime   = uplinkRange*GmatMathConstants::KM_TO_M / GmatPhysicalConstants::SPEED_OF_LIGHT_VACUUM;
		   downlinkTime = downlinkRange*GmatMathConstants::KM_TO_M / GmatPhysicalConstants::SPEED_OF_LIGHT_VACUUM;
		   #ifdef DEBUG_RANGE_CALC_WITH_EVENTS
		      MessageInterface::ShowMessage("  Ideal measurement (no hardware delay and no media correction involve):\n");
			  MessageInterface::ShowMessage("    Uplink time = %.12lf s\n",uplinkTime);
			  MessageInterface::ShowMessage("    Downlink time = %.12lf s\n",downlinkTime);
		   #endif

		   // Calculate real range
		   Real freqFactor = GetFrequencyFactor(frequency);	// Notice that: unit of "frequency" varaibel is Hz (not MHz)
		   Real realTravelTime = uplinkTime + downlinkTime + receiveDelay + transmitDelay + targetDelay;	// unit: second
		   Real realRangeKm = 0.5 *realTravelTime * GmatPhysicalConstants::SPEED_OF_LIGHT_VACUUM/1000.0;    // unit: km
		   Real realRange = realTravelTime * freqFactor;													// unit: no unit

		   #ifdef DEBUG_RANGE_CALC_WITH_EVENTS
		      MessageInterface::ShowMessage("   Frequency = %.12lf MHz (This value is set to the default value in PhysicalMeasurement class due to no hardware used.)\n", frequency/1.0e6);
			  MessageInterface::ShowMessage("   Frequency factor = %.12lf MHz\n", freqFactor/1.0e6);
	          MessageInterface::ShowMessage("   Range in km = %.12lf km\n", realRangeKm);
			  MessageInterface::ShowMessage("   uplinkRange = %lfkm   downlinkRange = %lfkm\n", uplinkRange, downlinkRange);
			  MessageInterface::ShowMessage("   receiveDelay = %lfm   transmitDelay = %lfm   targetDelay = %lfm\n", receiveDelay*GmatPhysicalConstants::SPEED_OF_LIGHT_VACUUM, transmitDelay*GmatPhysicalConstants::SPEED_OF_LIGHT_VACUUM, targetDelay*GmatPhysicalConstants::SPEED_OF_LIGHT_VACUUM);
	          MessageInterface::ShowMessage("   Range = %.12lf (It has no unit)\n", realRange);
	       #endif

	      // Set value for currentMeasurement
		   currentMeasurement.value[0] = realRange;
	      currentMeasurement.isFeasible = true;

	      return true;
	   }

		ObjectArray objList1;
		ObjectArray objList2;
		ObjectArray objList3;
		//			objList1 := all transmitters in participantHardware list
		//			objList2 := all receivers in participantHardware list
		//			objList3 := all transponders in participantHardware list
		for(std::vector<Hardware*>::iterator hw = this->participantHardware[0].begin();
		  		hw != this->participantHardware[0].end(); ++hw)
		{
		 	if ((*hw) != NULL)
		  	{
		  		if ((*hw)->GetTypeName() == "Transmitter")
		  			objList1.push_back(*hw);
		  		if ((*hw)->GetTypeName() == "Receiver")
		  			objList2.push_back(*hw);
		  	}
		  	else
		  		MessageInterface::ShowMessage(" sensor = NULL\n");
		}

		for(std::vector<Hardware*>::iterator hw = this->participantHardware[1].begin();
		  		hw != this->participantHardware[1].end(); ++hw)
		{
		  	if ((*hw) != NULL)
		  	{
		  		if ((*hw)->GetTypeName() == "Transponder")
		  			objList3.push_back(*hw);
		  	}
		  	else
		  		MessageInterface::ShowMessage(" sensor = NULL\n");
		}

		if (objList1.size() != 1)
		{
		  	MessageInterface::ShowMessage("The first participant does not have only 1 transmitter to send signal.\n");
		   throw new MeasurementException("The first participant does not have only 1 transmitter to send signal.\n");
		}
		if (objList2.size() != 1)
		{
		 	MessageInterface::ShowMessage("The first participant does not have only 1 receiver to receive signal.\n");
		   throw new MeasurementException("The first participant does not have only 1 receiver to receive signal.\n");
		}
		if (objList3.size() != 1)
		{
		  	MessageInterface::ShowMessage("The second participant does not have only 1 transponder to transpond signal.\n");
		  	throw new MeasurementException("The second participant does not have only 1 transponder to transpond signal.\n");
		}

	   Transmitter* 	gsTransmitter 	= (Transmitter*)objList1[0];
	   Receiver* 		gsReceiver 		= (Receiver*)objList2[0];
	   Transponder* 	scTransponder 	= (Transponder*)objList3[0];
	   if (gsTransmitter == NULL)
	   {
	   	MessageInterface::ShowMessage("Transmitter is NULL object.\n");
	   	throw new GmatBaseException("Transmitter is NULL object.\n");
	   }
	   if (gsReceiver == NULL)
	   {
	   	MessageInterface::ShowMessage("Receiver is NULL object.\n");
	   	throw new GmatBaseException("Receiver is NULL object.\n");
	   }
	   if (scTransponder == NULL)
	   {
	   	MessageInterface::ShowMessage("Transponder is NULL object.\n");
	   	throw new GmatBaseException("Transponder is NULL object.\n");
	   }

		#ifdef DEBUG_RANGE_CALC_WITH_EVENTS
	        MessageInterface::ShowMessage("5. Sensors, delays, and signals:\n");
			MessageInterface::ShowMessage("   List of sensors: %s, %s, %s\n",
				gsTransmitter->GetName().c_str(), gsReceiver->GetName().c_str(),
				scTransponder->GetName().c_str());
		#endif


		// 6. Get transmitter, receiver, and transponder delays:
		transmitDelay = gsTransmitter->GetDelay();
		receiveDelay = gsReceiver->GetDelay();
		targetDelay = scTransponder->GetDelay();

		#ifdef DEBUG_RANGE_CALC_WITH_EVENTS
			MessageInterface::ShowMessage("   Transmitter delay = %le s\n", gsTransmitter->GetDelay());
			MessageInterface::ShowMessage("   Receiver delay = %le s\n", gsReceiver->GetDelay());
			MessageInterface::ShowMessage("   Transponder delay = %le s\n", scTransponder->GetDelay());
		#endif


		// 7. Get frequency from transmitter of ground station (participants[0])
		Signal* uplinkSignal = gsTransmitter->GetSignal();
		Real uplinkFreq = uplinkSignal->GetValue();


        // 8. Calculate media correction for uplink leg:
        #ifdef DEBUG_RANGE_CALC_WITH_EVENTS   
           MessageInterface::ShowMessage("6. Media correction for uplink leg\n");
		   MessageInterface::ShowMessage("   UpLink signal frequency = %.12lf MHz\n", uplinkFreq);
        #endif
        Real roundTripTime = ((uplinkRange + downlinkRange)*GmatMathConstants::KM_TO_M/GmatPhysicalConstants::SPEED_OF_LIGHT_VACUUM)/GmatTimeConstants::SECS_PER_DAY;
        RealArray uplinkCorrection = CalculateMediaCorrection(uplinkFreq, r1, r2, currentMeasurement.epoch - roundTripTime);
        Real uplinkRangeCorrection = uplinkCorrection[0]/GmatMathConstants::KM_TO_M;
        Real uplinkRealRange = uplinkRange + uplinkRangeCorrection;
		#ifdef DEBUG_RANGE_CALC_WITH_EVENTS
			MessageInterface::ShowMessage("   Uplink range correction = %.12lf km\n",uplinkRangeCorrection);
			MessageInterface::ShowMessage("   Uplink real range = %.12lf km\n",uplinkRealRange);
		#endif


		// 9. Doppler shift the frequency from the transmitter using uplinkRangeRate:
	   Real uplinkDSFreq = (1 - uplinkRangeRate*GmatMathConstants::KM_TO_M/GmatPhysicalConstants::SPEED_OF_LIGHT_VACUUM)*uplinkFreq;

		#ifdef DEBUG_RANGE_CALC_WITH_EVENTS
	        MessageInterface::ShowMessage("7. Transponder input and output frequencies\n");
			MessageInterface::ShowMessage("   Uplink Doppler shift frequency = %.12lf MHz\n", uplinkDSFreq);
		#endif


	   // 10.Set frequency for the input signal of transponder
	   Signal* inputSignal = scTransponder->GetSignal(0);
	   inputSignal->SetValue(uplinkDSFreq);
	   scTransponder->SetSignal(inputSignal, 0);


	   // 11. Check the transponder feasibility to receive the input signal:
	   if (scTransponder->IsFeasible(0) == false)
	   {
	   	 currentMeasurement.isFeasible = false;
	   	 currentMeasurement.value[0] = 0;
	   	 MessageInterface::ShowMessage("The transponder is unfeasible to receive uplink signal.\n");
	   	 throw new GmatBaseException("The transponder is unfeasible to receive uplink signal.\n");
	   }


	   // 12. Get frequency of transponder output signal
	   Signal* outputSignal = scTransponder->GetSignal(1);
	   Real downlinkFreq = outputSignal->GetValue();

		#ifdef DEBUG_RANGE_CALC_WITH_EVENTS
			MessageInterface::ShowMessage("  Downlink frequency = %.12lf Mhz\n", downlinkFreq);
		#endif


	   // 13. Doppler shift the transponder output frequency by the downlinkRangeRate:
	   Real downlinkDSFreq = (1 - downlinkRangeRate*GmatMathConstants::KM_TO_M/GmatPhysicalConstants::SPEED_OF_LIGHT_VACUUM)*downlinkFreq;

	   #ifdef DEBUG_RANGE_CALC_WITH_EVENTS
			MessageInterface::ShowMessage("  Downlink Doppler shift frequency = %.12lf MHz\n", downlinkDSFreq);
		#endif


	   // 14. Set frequency on receiver
	   Signal* downlinkSignal = gsReceiver->GetSignal();
	   downlinkSignal->SetValue(downlinkDSFreq);


	   // 15. Check the receiver feasibility to receive the downlink signal
	   if (gsReceiver->IsFeasible() == false)
	   {
	   	 currentMeasurement.isFeasible = false;
	   	 currentMeasurement.value[0] = 0;
		 MessageInterface::ShowMessage("The receiver is unfeasible to receive downlink signal.\n");
	   	 throw new MeasurementException("The receiver is unfeasible to receive downlink signal.\n");
	   }


	   // 16. Calculate media correction for downlink leg:
      #ifdef DEBUG_RANGE_CALC_WITH_EVENTS
         MessageInterface::ShowMessage("8. Media correction for downlink leg\n");
      #endif
	   RealArray downlinkCorrection = CalculateMediaCorrection(downlinkDSFreq, r3, r4, currentMeasurement.epoch);
	   Real downlinkRangeCorrection = downlinkCorrection[0]/GmatMathConstants::KM_TO_M;
	   Real downlinkRealRange = downlinkRange + downlinkRangeCorrection;
		#ifdef DEBUG_RANGE_CALC_WITH_EVENTS
			MessageInterface::ShowMessage("   Downlink range correction = %.12lf km\n",downlinkRangeCorrection);
			MessageInterface::ShowMessage("   Downlink real range = %.12lf km\n",downlinkRealRange);
		#endif

	   // 17. Calculate uplink time and down link time: (Is it needed???)
	   uplinkTime   = uplinkRealRange*GmatMathConstants::KM_TO_M / GmatPhysicalConstants::SPEED_OF_LIGHT_VACUUM;
	   downlinkTime = downlinkRealRange*GmatMathConstants::KM_TO_M / GmatPhysicalConstants::SPEED_OF_LIGHT_VACUUM;

		#ifdef DEBUG_RANGE_CALC_WITH_EVENTS
	        MessageInterface::ShowMessage("9. Travel time:\n");
			MessageInterface::ShowMessage("   Uplink time = %.12lf s\n",uplinkTime);
			MessageInterface::ShowMessage("   Downlink time = %.12lf s\n",downlinkTime);
		#endif


	   // 18. Calculate real range
		//	   Real realRange = ((upRange + downRange) /
		//            (GmatPhysicalConstants::SPEED_OF_LIGHT_VACUUM / GmatMathConstants::KM_TO_M) +
		//            receiveDelay + transmitDelay + targetDelay) * freqFactor;

	   // Real freqFactor = GetFrequencyFactor(frequency);
	   Real freqFactor = GetFrequencyFactor(uplinkFreq*1.0e6);		// Notice that: unit of "uplinkFreq" is MHz (not Hz)
  	   Real realTravelTime = uplinkTime + downlinkTime + receiveDelay + transmitDelay + targetDelay;    // unit: second
	   Real realRangeKm = 0.5*realTravelTime * GmatPhysicalConstants::SPEED_OF_LIGHT_VACUUM/1000.0;		// unit: km
       Real realRange = realTravelTime * freqFactor;													// unit: no unit

	   #ifdef DEBUG_RANGE_CALC_WITH_EVENTS
		  MessageInterface::ShowMessage("   Frequency factor = %.12lf MHz\n", freqFactor/1.0e6);
		  MessageInterface::ShowMessage("   Calculated real range in km = %.12lf km\n", realRangeKm);
          MessageInterface::ShowMessage("   Calculated real range = %.12lf (It has no unit)\n", realRange);
       #endif



	   // 19. Set value for currentMeasurement
//	   currentMeasurement.value[0] = realRange;
      currentMeasurement.value[0] = realRangeKm;
      currentMeasurement.isFeasible = true;

      retval = true;
   }

   return retval;
}