Description

Provides access to the properties and methods defining the RF environment.

Object Model

Public Properties

ActiveCommSystem	Gets or sets the active CommSystem object.
ContourRainOutagePercent	Gets or sets the contour rain outage percent.
EarthTemperature	Gets or sets the earth temperature.
PropagationChannel	Gets the propagation channel.
SupportedActiveCommSystems	Gets an array of supported active CommSystem objects.
SupportedContourRainOutagePercentValues	Gets an array of supported contour rain outage percent values.

Example

Compute the probability of detection of a target for a monostatic search/track radar

[C#] Copy Code

IAgStkObject rdrAsStkObject = radar as IAgStkObject; 

IAgStkObject tgtAsStkObject = targetAircraft as IAgStkObject; 

 

//Enable the rain loss computation on the scenario RF environment 

scenarioRFEnv.PropagationChannel.EnableRainLoss = true; 

 

//Configure the radar object as a monostatic model. 

radar.SetModel("Monostatic"); 

IAgRadarModelMonostatic monostaticModel = radar.Model as IAgRadarModelMonostatic; 

 

//Orient the radar antenna in the direction of the target 

radar.Model.AntennaControl.EmbeddedModelOrientation.AssignAzEl(50.9, 36.8, AgEAzElAboutBoresight.eAzElAboutBoresightRotate); 

 

//Set the radar antenna model to parabolic 

radar.Model.AntennaControl.SetEmbeddedModel("Parabolic"); 

IAgAntennaModelParabolic parabolic = radar.Model.AntennaControl.EmbeddedModel as IAgAntennaModelParabolic; 

 

//Give the parabolic antenna a 2 deg beamwidth; 

parabolic.InputType = AgEAntennaModelInputType.eAntennaModelInputTypeBeamwidth; 

parabolic.Beamwidth = 2.0; 

 

//Put the monostatic radar model in Search/Track mode 

monostaticModel.SetMode("Search Track"); 

IAgRadarModeMonostaticSearchTrack searchTrackMode = monostaticModel.Mode as IAgRadarModeMonostaticSearchTrack; 

 

//Set the waveform type to fixed prf 

searchTrackMode.SetWaveformType(AgERadarWaveformSearchTrackType.eRadarWaveformSearchTrackTypeFixedPRF); 

IAgRadarWaveformMonostaticSearchTrackFixedPRF fixedPrf = searchTrackMode.Waveform as IAgRadarWaveformMonostaticSearchTrackFixedPRF; 

fixedPrf.PulseDefinition.Prf = 0.002; //2 kHz 

 

//Set the pulse width to 1e-8 sec 

fixedPrf.PulseDefinition.PulseWidth = 1.0e-8; //sec 

 

//Set the number of pulses 

fixedPrf.PulseDefinition.NumberOfPulses = 25; 

 

//Set the pulse integration strategy to goal SNR 

fixedPrf.PulseIntegrationType = AgERadarPulseIntegrationType.eRadarPulseIntegrationTypeGoalSNR; 

IAgRadarPulseIntegrationGoalSNR pulseIntGoalSNR = fixedPrf.PulseIntegration as IAgRadarPulseIntegrationGoalSNR; 

pulseIntGoalSNR.SNR = 40.0; //dB 

 

//Set the transmit frequency 

monostaticModel.Transmitter.FrequencySpecification = AgERadarFrequencySpec.eRadarFrequencySpecFrequency; 

monostaticModel.Transmitter.Frequency = 2.1; //GHz 

 

//Set the transmit power 

monostaticModel.Transmitter.Power = 50.0; //dBW 

 

//Enable rain loss computation on the receiver 

monostaticModel.Receiver.UseRain = true; 

monostaticModel.Receiver.RainOutagePercent = 0.001; 

 

//Enable the receiver system noise temperature computation. 

monostaticModel.Receiver.SystemNoiseTemperature.ComputeType = AgENoiseTempComputeType.eNoiseTempComputeTypeCalculate; 

 

//Enable the antenna noise temperature computation 

monostaticModel.Receiver.SystemNoiseTemperature.AntennaNoiseTemperature.ComputeType = AgENoiseTempComputeType.eNoiseTempComputeTypeCalculate; 

monostaticModel.Receiver.SystemNoiseTemperature.AntennaNoiseTemperature.UseRain = true; 

 

//Don't inherit the radar cross section settings from the scenario 

targetAircraft.RadarCrossSection.Inherit = false; 

IAgRadarCrossSectionModel rcs = targetAircraft.RadarCrossSection.Model as IAgRadarCrossSectionModel; 

 

//Set the radar cross section compute strategy to constan value 

rcs.FrequencyBands[0].SetComputeStrategy("Constant Value"); 

IAgRadarCrossSectionComputeStrategyConstantValue constValRcs = 

    rcs.FrequencyBands[0].ComputeStrategy as IAgRadarCrossSectionComputeStrategyConstantValue; 

 

//Set the constant radar cross section to 0.5 dBsm 

constValRcs.ConstantValue = 0.5; //dBsm 

 

//Create an access object for the access between the radar and target 

IAgStkAccess radarAccess = rdrAsStkObject.GetAccessToObject(tgtAsStkObject); 

 

//Compute access 

radarAccess.ComputeAccess(); 

 

// Get the access intervals 

IAgIntervalCollection accessIntervals = radarAccess.ComputedAccessIntervalTimes; 

 

// Extract the access intervals and the range information for each access interval 

Array dataPrvElements = new object[] { "Time", "S/T SNR1", "S/T PDet1", "S/T Integrated SNR", "S/T Integrated PDet" }; 

 

IAgDataPrvTimeVar dp = radarAccess.DataProviders["Radar SearchTrack"] as IAgDataPrvTimeVar; 

 

for (int index0 = 0; index0 < accessIntervals.Count; ++index0) 

{ 

    object startTime = null, stopTime = null; 

    accessIntervals.GetInterval(index0, out startTime, out stopTime); 

 

    IAgDrResult result = dp.ExecElements(startTime, stopTime, 60, ref dataPrvElements); 

 

    Array timeValues = result.DataSets.GetDataSetByName("Time").GetValues(); 

    Array snr1 = result.DataSets.GetDataSetByName("S/T SNR1").GetValues(); 

    Array pdet1 = result.DataSets.GetDataSetByName("S/T PDet1").GetValues(); 

    Array integSnr = result.DataSets.GetDataSetByName("S/T Integrated SNR").GetValues(); 

    Array integPdet = result.DataSets.GetDataSetByName("S/T Integrated PDet").GetValues(); 

 

    for (int index1 = 0; index1 < timeValues.GetLength(0); ++index1) 

    { 

        string time = (string)timeValues.GetValue(index1); 

        double snr1Val = (double)snr1.GetValue(index1); 

        double pdet1Val = (double)pdet1.GetValue(index1); 

        double integSnrVal = (double)integSnr.GetValue(index1); 

        double integPdetVal = (double)integPdet.GetValue(index1); 

        Console.WriteLine("{0}: SNR1={1} PDet1={2} Integrated SNR={3} Integrated PDet={4}", time, snr1Val, pdet1Val, integSnrVal, integPdetVal); 

    } 

 

    Console.WriteLine(); 

}

Compute a link budget for a Transmtiter and Receiver pair, using complex models

[C#] Copy Code

IAgStkObject xmtrAsStkObject = geoTransmitter as IAgStkObject; 

IAgStkObject rcvrAsStkObject = facilityReceiver as IAgStkObject; 

 

//Enable the rain loss computation on the scenario RF environment 

scenarioRFEnv.PropagationChannel.EnableRainLoss = true; 

 

//Set the transmitter to the complex model 

geoTransmitter.SetModel("Complex Transmitter Model"); 

IAgTransmitterModelComplex complexTrans = geoTransmitter.Model as IAgTransmitterModelComplex; 

 

//Set the complex transmitter model's frequency to 3.2 GHz 

complexTrans.Frequency = 3.2; 

 

//Set the complex transmitter model's Power to 50 dBW 

complexTrans.Power = 50.0; 

 

//Set the complex transmitter's embedded antenna model to helix 

complexTrans.AntennaControl.SetEmbeddedModel("Helix"); 

 

//Set the beamwidth of the parablic antenna to 2 degrees 

IAgAntennaModelHelix helix = complexTrans.AntennaControl.EmbeddedModel as IAgAntennaModelHelix; 

helix.NumberOfTurns = 30.0; 

 

//Orient the complex transmitter embedded antenna's boresight to point directly at the receiver's location 

complexTrans.AntennaControl.EmbeddedModelOrientation.AssignAzEl(287.2, 83.4, AgEAzElAboutBoresight.eAzElAboutBoresightRotate); 

 

//Set the receiver to the complex model 

facilityReceiver.SetModel("Complex Receiver Model"); 

IAgReceiverModelComplex complexRcvr = facilityReceiver.Model as IAgReceiverModelComplex; 

 

//Configure the complex receiver to use the antenna object on the same parent facility, by linking 

complexRcvr.AntennaControl.ReferenceType = AgEAntennaControlRefType.eAntennaControlRefTypeLink; 

complexRcvr.AntennaControl.LinkedAntennaObject = "Antenna/FacilityDish"; 

 

//Enable rain loss computation on the receiver 

complexRcvr.UseRain = true; 

complexRcvr.RainOutagePercent = 0.001; 

 

//Enable the receiver system noise temperature computation. 

complexRcvr.SystemNoiseTemperature.ComputeType = AgENoiseTempComputeType.eNoiseTempComputeTypeCalculate; 

 

//Enable the antenna noise temperature computation 

complexRcvr.SystemNoiseTemperature.AntennaNoiseTemperature.ComputeType = AgENoiseTempComputeType.eNoiseTempComputeTypeCalculate; 

complexRcvr.SystemNoiseTemperature.AntennaNoiseTemperature.UseRain = true; 

 

//Orient the antenna object's boresight to point directly at the transmitter's location 

facilityDish.Orientation.AssignAzEl(202.6, 41.2, AgEAzElAboutBoresight.eAzElAboutBoresightRotate); 

 

//Set the antenna object's model to parabolic 

facilityDish.SetModel("Parabolic"); 

 

//Set the antenan object's design frequency to match the transmitter's 3.2 GHz 

facilityDish.Model.DesignFrequency = 3.2; 

 

//Set the antenna object's parabolic model diameter to 5 m. 

IAgAntennaModelParabolic parabolic = facilityDish.Model as IAgAntennaModelParabolic; 

parabolic.InputType = AgEAntennaModelInputType.eAntennaModelInputTypeDiameter; 

parabolic.Diameter = 5.0; 

 

//Create an access object for the access between the transmitter and recevier objects 

IAgStkAccess linkAccess = xmtrAsStkObject.GetAccessToObject(rcvrAsStkObject); 

 

//Compute access 

linkAccess.ComputeAccess(); 

 

// Get the access intervals 

IAgIntervalCollection accessIntervals = linkAccess.ComputedAccessIntervalTimes; 

 

// Extract the access intervals and the range information for each access interval 

Array dataPrvElements = new object[] { "Time", "Xmtr Gain", "Rcvr Gain", "Eb/No", "BER" }; 

 

IAgDataPrvTimeVar dp = linkAccess.DataProviders["Link Information"] as IAgDataPrvTimeVar; 

 

for (int index0 = 0; index0 < accessIntervals.Count; ++index0) 

{ 

    object startTime = null, stopTime = null; 

 

    accessIntervals.GetInterval(index0, out startTime, out stopTime); 

 

    IAgDrResult result = dp.ExecElements(startTime, stopTime, 60, ref dataPrvElements); 

 

    Array timeValues = result.DataSets[0].GetValues(); 

    Array xmtrGain = result.DataSets[1].GetValues(); 

    Array rcvrGain = result.DataSets[2].GetValues(); 

    Array ebno = result.DataSets[3].GetValues(); 

    Array ber = result.DataSets[4].GetValues(); 

 

    for (int index1 = 0; index1 < timeValues.GetLength(0); ++index1) 

    { 

        string time = (string)timeValues.GetValue(index1); 

        double xmtrGainVal = (double)xmtrGain.GetValue(index1); 

        double rcvrGainVal = (double)rcvrGain.GetValue(index1); 

        double ebnoVal = (double)ebno.GetValue(index1); 

        double berVal = (double)ber.GetValue(index1); 

        Console.WriteLine("{0}: Xmtr Gain = {1} Rcvr Gain = {2} Eb/No={3} BER={4}", time, xmtrGainVal, rcvrGainVal, ebnoVal, berVal); 

    } 

 

    Console.WriteLine(); 

}

Compute a link budget for a Transmtiter and Receiver pair, using complex models

[Visual Basic .NET] Copy Code

Dim xmtrAsStkObject As IAgStkObject = TryCast(geoTransmitter, IAgStkObject)
Dim rcvrAsStkObject As IAgStkObject = TryCast(facilityReceiver, IAgStkObject)

'Enable the rain loss computation on the scenario RF environment
 scenarioRFEnv.PropagationChannel.EnableRainLoss = True

'Set the transmitter to the complex model
 geoTransmitter.SetModel("Complex Transmitter Model")
Dim complexTrans As IAgTransmitterModelComplex = TryCast(geoTransmitter.Model, IAgTransmitterModelComplex)

'Set the complex transmitter model's frequency to 3.2 GHz
 complexTrans.Frequency = 3.2

'Set the complex transmitter model's Power to 50 dBW
 complexTrans.Power = 50

'Set the complex transmitter's embedded antenna model to helix
 complexTrans.AntennaControl.SetEmbeddedModel("Helix")

'Set the beamwidth of the parablic antenna to 2 degrees
Dim helix As IAgAntennaModelHelix = TryCast(complexTrans.AntennaControl.EmbeddedModel, IAgAntennaModelHelix)
 helix.NumberOfTurns = 30

'Orient the complex transmitter embedded antenna's boresight to point directly at the receiver's location
 complexTrans.AntennaControl.EmbeddedModelOrientation.AssignAzEl(287.2, 83.4, AgEAzElAboutBoresight.eAzElAboutBoresightRotate)

'Set the receiver to the complex model
 facilityReceiver.SetModel("Complex Receiver Model")
Dim complexRcvr As IAgReceiverModelComplex = TryCast(facilityReceiver.Model, IAgReceiverModelComplex)

'Configure the complex receiver to use the antenna object on the same parent facility, by linking
 complexRcvr.AntennaControl.ReferenceType = AgEAntennaControlRefType.eAntennaControlRefTypeLink
 complexRcvr.AntennaControl.LinkedAntennaObject = "Antenna/FacilityDish"

'Enable rain loss computation on the receiver
 complexRcvr.UseRain = True
 complexRcvr.RainOutagePercent = 0.001

'Enable the receiver system noise temperature computation.
 complexRcvr.SystemNoiseTemperature.ComputeType = AgENoiseTempComputeType.eNoiseTempComputeTypeCalculate

'Enable the antenna noise temperature computation
 complexRcvr.SystemNoiseTemperature.AntennaNoiseTemperature.ComputeType = AgENoiseTempComputeType.eNoiseTempComputeTypeCalculate
 complexRcvr.SystemNoiseTemperature.AntennaNoiseTemperature.UseRain = True

'Orient the antenna object's boresight to point directly at the transmitter's location
 facilityDish.Orientation.AssignAzEl(202.6, 41.2, AgEAzElAboutBoresight.eAzElAboutBoresightRotate)

'Set the antenna object's model to parabolic
 facilityDish.SetModel("Parabolic")

'Set the antenan object's design frequency to match the transmitter's 3.2 GHz
 facilityDish.Model.DesignFrequency = 3.2

'Set the antenna object's parabolic model diameter to 5 m.
Dim parabolic As IAgAntennaModelParabolic = TryCast(facilityDish.Model, IAgAntennaModelParabolic)
 parabolic.InputType = AgEAntennaModelInputType.eAntennaModelInputTypeDiameter
 parabolic.Diameter = 5

'Create an access object for the access between the transmitter and recevier objects
Dim linkAccess As IAgStkAccess = xmtrAsStkObject.GetAccessToObject(rcvrAsStkObject)

'Compute access
 linkAccess.ComputeAccess()

' Get the access intervals
Dim accessIntervals As IAgIntervalCollection = linkAccess.ComputedAccessIntervalTimes

' Extract the access intervals and the range information for each access interval
Dim dataPrvElements As Array = New Object() {"Time", "Xmtr Gain", "Rcvr Gain", "Eb/No", "BER"}
     accessIntervals.GetInterval(index0, startTime, stopTime)
     Dim result As IAgDrResult = dp.ExecElements(startTime, stopTime, 60, dataPrvElements)

Compute the probability of detection of a target for a monostatic search/track radar

[Visual Basic .NET] Copy Code

Dim rdrAsStkObject As IAgStkObject = TryCast(radar, IAgStkObject)
Dim tgtAsStkObject As IAgStkObject = TryCast(targetAircraft, IAgStkObject)

'Enable the rain loss computation on the scenario RF environment
 scenarioRFEnv.PropagationChannel.EnableRainLoss = True

'Configure the radar object as a monostatic model.
 radar.SetModel("Monostatic")
Dim monostaticModel As IAgRadarModelMonostatic = TryCast(radar.Model, IAgRadarModelMonostatic)

'Orient the radar antenna in the direction of the target
 radar.Model.AntennaControl.EmbeddedModelOrientation.AssignAzEl(50.9, 36.8, AgEAzElAboutBoresight.eAzElAboutBoresightRotate)

'Set the radar antenna model to parabolic
 radar.Model.AntennaControl.SetEmbeddedModel("Parabolic")
Dim parabolic As IAgAntennaModelParabolic = TryCast(radar.Model.AntennaControl.EmbeddedModel, IAgAntennaModelParabolic)

'Give the parabolic antenna a 2 deg beamwidth;
 parabolic.InputType = AgEAntennaModelInputType.eAntennaModelInputTypeBeamwidth
 parabolic.Beamwidth = 2

'Put the monostatic radar model in Search/Track mode
 monostaticModel.SetMode("Search Track")
Dim searchTrackMode As IAgRadarModeMonostaticSearchTrack = TryCast(monostaticModel.Mode, IAgRadarModeMonostaticSearchTrack)

'Set the waveform type to fixed prf
 searchTrackMode.SetWaveformType(AgERadarWaveformSearchTrackType.eRadarWaveformSearchTrackTypeFixedPRF)
Dim fixedPrf As IAgRadarWaveformMonostaticSearchTrackFixedPRF = TryCast(searchTrackMode.Waveform, IAgRadarWaveformMonostaticSearchTrackFixedPRF)
 fixedPrf.PulseDefinition.Prf = 0.002
'2 kHz
'Set the pulse width to 1e-8 sec
 fixedPrf.PulseDefinition.PulseWidth = 1E-08
'sec
'Set the number of pulses
 fixedPrf.PulseDefinition.NumberOfPulses = 25

'Set the pulse integration strategy to goal SNR
 fixedPrf.PulseIntegrationType = AgERadarPulseIntegrationType.eRadarPulseIntegrationTypeGoalSNR
Dim pulseIntGoalSNR As IAgRadarPulseIntegrationGoalSNR = TryCast(fixedPrf.PulseIntegration, IAgRadarPulseIntegrationGoalSNR)
 pulseIntGoalSNR.SNR = 40
'dB
'Set the transmit frequency
 monostaticModel.Transmitter.FrequencySpecification = AgERadarFrequencySpec.eRadarFrequencySpecFrequency
 monostaticModel.Transmitter.Frequency = 2.1
'GHz
'Set the transmit power
 monostaticModel.Transmitter.Power = 50
'dBW
'Enable rain loss computation on the receiver
 monostaticModel.Receiver.UseRain = True
 monostaticModel.Receiver.RainOutagePercent = 0.001

'Enable the receiver system noise temperature computation.
 monostaticModel.Receiver.SystemNoiseTemperature.ComputeType = AgENoiseTempComputeType.eNoiseTempComputeTypeCalculate

'Enable the antenna noise temperature computation
 monostaticModel.Receiver.SystemNoiseTemperature.AntennaNoiseTemperature.ComputeType = AgENoiseTempComputeType.eNoiseTempComputeTypeCalculate
 monostaticModel.Receiver.SystemNoiseTemperature.AntennaNoiseTemperature.UseRain = True

'Don't inherit the radar cross section settings from the scenario
 targetAircraft.RadarCrossSection.Inherit = False
Dim rcs As IAgRadarCrossSectionModel = TryCast(targetAircraft.RadarCrossSection.Model, IAgRadarCrossSectionModel)

'Set the radar cross section compute strategy to constan value
 rcs.FrequencyBands(0).SetComputeStrategy("Constant Value")
Dim constValRcs As IAgRadarCrossSectionComputeStrategyConstantValue = TryCast(rcs.FrequencyBands(0).ComputeStrategy, IAgRadarCrossSectionComputeStrategyConstantValue)

'Set the constant radar cross section to 0.5 dBsm
 constValRcs.ConstantValue = 0.5
'dBsm
'Create an access object for the access between the radar and target
Dim radarAccess As IAgStkAccess = rdrAsStkObject.GetAccessToObject(tgtAsStkObject)

'Compute access
 radarAccess.ComputeAccess()

' Get the access intervals
Dim accessIntervals As IAgIntervalCollection = radarAccess.ComputedAccessIntervalTimes

' Extract the access intervals and the range information for each access interval
Dim dataPrvElements As Array = New Object() {"Time", "S/T SNR1", "S/T PDet1", "S/T Integrated SNR", "S/T Integrated PDet"}
     accessIntervals.GetInterval(index0, startTime, stopTime)
     Dim result As IAgDrResult = dp.ExecElements(startTime, stopTime, 60, dataPrvElements)

CoClasses that Implement IAgRFEnvironment

Name
AgRFEnvironment

AGI STK Objects 11	Send comments on this topic.
IAgRFEnvironment Interface