Console.Dimension = 40;
Console.WordWrap  = 1;
Console.DockMode  = 3;
Console.BackColor = ColorTools.Black;
Console.CurrentTextColor = ColorTools.Lime;
Console.WindowTitle = "ODIN RF Link Analysis";
Console.Show();
 
Report "ODIN RF Link Analysis" to Console;
Report "" to Console;
 
Console.CurrentTextColor = ColorTools.White;
Report "  Frequency     	: 8.4 GHz (X-band)" to Console;
Report "  HGA modulation	: QPSK + CCSDS LDPC rate 1/3" to Console;
Report "  LGA modulation	: BPSK residual-carrier TT&C" to Console;
Report "  Transmitter   	: 70 W TWTA (TH4704C), 1.1 m steered HGA" to Console;
Report "  Ground stations	: Cebreros, Malargue, New Norcia (35 m)" to Console;
Report "  Duration       	: 1500 days from Oct 01 2026" to Console;
Console.CurrentTextColor = ColorTools.Lime;
Report "" to Console;
 
Report "MODE 0 — LGA TT&C (default)" to Console;
Console.CurrentTextColor = ColorTools.SteelBlue;
Report "  Always active. Low-rate BPSK. No imaging." to Console;
Console.CurrentTextColor = ColorTools.Lime;
Report "" to Console;
 
Report "MODE 1 — INSPECTION (near Solar Orbiter)" to Console;
Console.CurrentTextColor = ColorTools.Green;
Report "  Inspection windows (CDR 14-day campaigns):" to Console;
Report "    Insp 1: Feb 08-22 2028     (day 495-509)" to Console;
Report "    Insp 2: Nov 21-Dec 06 2028 (day 782-797)" to Console;
Console.CurrentTextColor = ColorTools.Lime;
Report "" to Console;
 
Report "MODE 2 — HGA DOWNLINK (Earth approach)" to Console;
Console.CurrentTextColor = ColorTools.Yellow;
Report "  Downlink: geometry-driven every step" to Console;
Report "    (station visible past Earth/Sun occultation" to Console;
Report "     AND link margin >= 6 dB CDR floor)." to Console;
Console.CurrentTextColor = ColorTools.Lime;
Report "" to Console;
 
// ============================================================================
// FREEFORM 2 — Global Constants and Variables Definitions
// ============================================================================
 
// ----------------------------------------------------------------------------
// STEP MODE CONSTANTS
// ----------------------------------------------------------------------------
 
Global Constant Variable STEP_MODE_STEP      = 0;
Global Constant Variable STEP_MODE_STEP_TO   = 1;
Global Constant Variable STEP_MODE_SET_STATE = 2;
 
// ----------------------------------------------------------------------------
// SIMULATION MODE CONSTANTS
// ----------------------------------------------------------------------------
 
Global Constant Variable SIM_MODE_SC_TO_GS = 0;
Global Constant Variable SIM_MODE_SC_TO_SC = 1;

// ----------------------------------------------------------------------------
// ODIN OPERATING MODE CONSTANTS
//   0 = LGA TT&C  (default / safe)
//   1 = Inspection (near Solar Orbiter, cameras active)
//   2 = HGA Downlink (Earth approach, SSM drain)
// ----------------------------------------------------------------------------
 
Global Constant Variable MODE_LGA_TTC       = 0;
Global Constant Variable MODE_INSPECTION    = 1;
Global Constant Variable MODE_HGA_DOWNLINK  = 2;

// Current operating mode (updated each propagation step)
Global Variable currentMode;
currentMode = 0;

// ----------------------------------------------------------------------------
// INSPECTION PROXIMITY THRESHOLD
// ODIN enters MODE_INSPECTION when it is within this range of Solar Orbiter.
// ----------------------------------------------------------------------------
 
Global Variable inspectionThresholdKm;
inspectionThresholdKm = 5000000.0; //arbitrary 
 
// Range from ODIN to Solar Orbiter (computed each step)
Global Variable odinToSORange;
odinToSORange = 0.0;
 
// ----------------------------------------------------------------------------
// SIMULATION TIMING
// ----------------------------------------------------------------------------
 
Global TimeSpan simulationStepSize;
simulationStepSize = TIMESPAN(1 hours);
 
Global TimeSpan simulationDuration;
simulationDuration = TIMESPAN(1500 days);
// ----------------------------------------------------------------------------
// DATA STORAGE MODEL
// Imaging: ~1 Mbps compressed = 0.36 GB/hr
// HGA downlink at 20 kbps = ~0.009 GB/hr
// Refine these values as the mission design matures.
// ----------------------------------------------------------------------------
 
Global Variable onboardDataGB;
onboardDataGB = 0.0;
 
Global Variable storageCapacityGB;
storageCapacityGB = 256.0;  //again, arbitrary 
 
Global Variable imagingRateGBperHour;
imagingRateGBperHour = 0.36;
 
Global Variable downlinkRateGBperHour;
downlinkRateGBperHour = 0.009;
 
// ----------------------------------------------------------------------------
// FILE PATHS
// ----------------------------------------------------------------------------
 
String AntennaPatternFilename;
AntennaPatternFilename = "C:\Users\horip\Downloads\FreeFlyer\Sample Mission Plans\_Support_Files\Antenna_Patterns\Antenna_Pattern_Example_ThetaPhi.txt";
 
String VehicleEphemerisFilename;
VehicleEphemerisFilename = "";
 
// ----------------------------------------------------------------------------
// GROUND STATION LIST
// ----------------------------------------------------------------------------
 
List<GroundStation> gsTargets[3];
 
// ----------------------------------------------------------------------------
// PLOT SERIES
// ----------------------------------------------------------------------------
 
List<PlotScatterSeries> powerToTargetData[3];
List<PlotScatterSeries> signalToNoiseData[3];
List<PlotScatterSeries> RFLinkMargin[3];
List<PlotScatterSeries> dataRateData[3];
 
// ----------------------------------------------------------------------------
// COORDINATE SYSTEMS AND GRAPHICS OVERLAYS
// ----------------------------------------------------------------------------
 
CoordinateSystem csSource;
 
GraphicsOverlay velocityGo;
GraphicsOverlay antennaModelGo;
GraphicsOverlay transmitterGo;
 
// ----------------------------------------------------------------------------
// DUMMY SPACECRAFT FOR ANTENNA PATTERN VISUALIZATION ONLY
// Do NOT use this object for RF calculations.
// ----------------------------------------------------------------------------
 
Spacecraft RFTargetAntenna;
 
// ----------------------------------------------------------------------------
// SIMULATION CONTROL FLAGS
// ----------------------------------------------------------------------------
 
Variable animateView;
animateView = 1;
 
Variable animateGainView;
animateGainView = 1;
 
Variable calcDownLink;
calcDownLink = 1;
 
Variable SimMode;
SimMode = SIM_MODE_SC_TO_GS;
 
Variable UseEphemerisForSource;
UseEphemerisForSource = 0;
 
Variable numberOfGroundStations;
numberOfGroundStations = 3;
 
// ----------------------------------------------------------------------------
// LINK BUDGET PARAMETERS
// ----------------------------------------------------------------------------
 
Variable lbFrequencyGHz        = 8.42;
Variable lbTxPowerW            = 70.0;
Variable lbTxAntennaDiamM      = 1.10;
Variable lbTxEfficiency        = 0.468;
Variable lbRxAntennaDiamM      = 35.0;
Variable lbRxEfficiency        = 0.55;
Variable lbSystemNoiseTempK    = 80.0;
Variable lbDataRateHz          = 20000.0;
Variable lbBandwidthHz         = 1.0e6;
Variable lbTxLineLossdB        = 1.0;
Variable lbPointingLossdB      = 0.01;
Variable lbPolarizationLossdB  = 0.2;
Variable lbAtmosphericLossdB   = 0.5;
Variable lbImplementationLossdB = 2.0;
Variable lbRequiredEbNodB      = 0.59;
Variable lbBoltzmannDB         = -228.6;
Variable lbPi                  = 3.141592653589793;
 
// Precomputed link budget values
Variable lbWavelengthM;
Variable lbTxPowerdBW;
Variable lbTxGaindBi;
Variable lbRxGaindBi;
Variable lbEIRPdBW;
Variable lbNoDensitydBWHZ;
Variable lbNoisePowerdBW;
 
// Per-step calculation variables
Variable lbRangeKm;
Variable lbFreeSpaceLossdB;
Variable lbTotalLossdB;
Variable lbEbNodB;
 
Variable recPr;
Variable recCtoN;
Variable linkMargin;
 
// Best-station selection variables
Variable bestLinkMargin;
Variable bestStationIndex;
Variable bestReceivedPower;
Variable bestCtoN;
Variable bestRangeKm;
Variable pointIsReasonable;

// Geometry-driven downlink (added — replaces hardcoded day windows)
Variable earthRangeKm;
Variable earthRangeAU;
Variable downlinkAvailable = 0;
Variable downlinkMarginThresholdDB = 6.0;   // dB — CDR SSR-COMM-03 margin floor

// Adaptive downlink data rate (CDR Table 12.5.13): rate chosen each step to hold
// exactly the 6 dB margin floor, capped at the 89 kbps CDR peak.
Variable lbMaxDataRateHz    = 89000.0;      // Hz — CDR peak downlink rate
Variable lbMinUsefulRateHz  = 1000.0;       // Hz — below this, no HGA downlink counted
Variable lbAchievableRateHz = 0.0;          // Hz — computed each step
Variable AU_KM = 149597870.7;               // km per astronomical unit

// Loop and counter variables
Variable gsToUse          = 0;
Variable inView           = 0;
Variable elapsedDays      = 0;
Variable daysSinceStart   = 0;
Variable lbValidPointCount = 0;
Variable lbViewCounter    = 0;
Variable isInDownlinkWindow = 0;
Variable isInInspectionWindow = 0;
Variable modeReportCounter = 0;

TimeSpan initialEpoch;
 
// ----------------------------------------------------------------------------
// VECTORS AND VISIBILITY
// ----------------------------------------------------------------------------
 
Vector angVector;
Vector commVector;
Vector velVector;
 
VisibilitySegment visSeg;
 
// ----------------------------------------------------------------------------
// WINDOW OVERLAYS
// ----------------------------------------------------------------------------
 
WindowOverlay woWindowFrame;
WindowOverlay epochWo;
WindowOverlay modeWo;
 
// ----------------------------------------------------------------------------
// PLOT WINDOWS
// ----------------------------------------------------------------------------
 
PlotWindow powerPlot;
PlotWindow signalToNoisePlot;
PlotWindow rfLinkPlot;
PlotWindow dataRatePlot;
 
// ----------------------------------------------------------------------------
// VIEW WINDOWS
// ----------------------------------------------------------------------------
 
ViewWindow antennaGainView({RFTargetAntenna, antennaModelGo});
ViewWindow vehicleView({ODIN, commVector, velVector, transmitterGo});
ViewWindow orbitView({ODIN, SolarOrbiter, commVector});

// ----------------------------------------------------------------------------
// COLOR ALIASES
// ----------------------------------------------------------------------------
 
Alias gsColor_1 = ColorTools.SteelBlue;
Alias gsColor_2 = ColorTools.OrangeRed;
Alias gsColor_3 = ColorTools.Lime;

Alias soColor   = ColorTools.Gold;
 
// ----------------------------------------------------------------------------
// ANTENNA GAIN VIEW ALIASES
// ----------------------------------------------------------------------------

Alias tdv       = antennaGainView.CurrentViewpoint.ThreeDView;
Alias currentVp = antennaGainView.CurrentViewpoint;
// ============================================================================
// FREEFORM 3 — Define Procedures and Configure Objects
// ============================================================================
 
// ----------------------------------------------------------------------------
// Common spacecraft configuration
// ----------------------------------------------------------------------------
 
Define Procedure CommonConfigurations(Spacecraft sc);
 
    sc.BodyScale = 500;
    sc.Propagator.StepSize = simulationStepSize;
 
    Alias sens = sc.Sensors[0];
    sens.ConeHalfAngle    = 2;
    sens.ProjectionHeight = 5;
    sens.Active           = 0;
 
EndProcedure;
 
// ----------------------------------------------------------------------------
// Configure ODIN as the inspection spacecraft
// ----------------------------------------------------------------------------
 
Define Procedure ConfigureSource(Spacecraft source, CoordinateSystem orientation);
 
    source.AddSensor("source_sensor");
 
    Alias sens = source.Sensors[0];
    sens.Color               = ColorTools.Red;
    sens.BoresightUnitVector = {-1, 0, 0};
 
    source.AttitudeRefFrame  = "MJ2000";
 
    Call CommonConfigurations(source);
 
    source.BodyScale   = 500;
    source.DisplayName = "ODIN";
 
EndProcedure;
 
// ----------------------------------------------------------------------------
// Configure RFLink1 for HGA downlink (MODE 2)
// Transmitter: ODIN 1.1 m HGA, 55 W
// Receiver:    ESA 35 m ground station, 80 K
// ----------------------------------------------------------------------------
 
// CORRECT:
Define Procedure ConfigureInspectionDownlink(RFLink link, Spacecraft source, GroundStation receiver, String antennaPatternFile);
 // General RFLink properties
    link.Frequency        = 8420;       // MHz — X-band downlink (CDR Table 12.5.13)
    link.Bandwidth        = 36;         // MHz
    link.AtmosphericLoss  = 0.5;        // dB — CDR
    link.PolarizationLoss = 0.2;        // dB — CDR (pol + GS line)
    link.ModulationType   = "QPSK";     // FIX: was BPSK — architecture specifies QPSK + LDPC
    link.BitRate          = 20000;      // bps — 20 kbps baseline
    link.LinkPowerMargin  = 6.0;        // dB — CDR SSR-COMM-03 margin floor
 
    // Transmitter: ODIN HGA
    link.Transmitter.SetReferenceObject(source);
    link.Transmitter.AntennaDiameter   = 1.1;     // m
    link.Transmitter.AntennaEfficiency = 0.468;   // CDR — reproduces 36.42 dBi HGA gain
    link.Transmitter.Power             = 70;      // W — TWTA TH4704C (CDR)
    link.Transmitter.NoiseTemperature  = 1500;    // K
    link.Transmitter.LineLoss          = 1.0;     // dB — CDR
    link.Transmitter.PointingLoss      = 0.01;    // dB — steered HGA (CDR)
    link.Transmitter.LoadAntennaGainFile(antennaPatternFile);
 
    // Receiver: ESA 35 m deep-space ground station
    link.Receiver.SetReferenceObject(receiver);
    link.Receiver.AntennaDiameter   = 35.0;       // m  
    link.Receiver.AntennaEfficiency = 0.55;
    link.Receiver.Power             = 1;          // W  
    link.Receiver.NoiseTemperature  = 80;         // K  
    link.Receiver.LineLoss          = 2.0;        // dB
    link.Receiver.PointingLoss      = 0.5;        // dB
EndProcedure;

// ----------------------------------------------------------------------------
// Configure plot window appearance
// ----------------------------------------------------------------------------
 
Define Procedure ConfigurePlotWindow(PlotWindow pw);
 
    pw.PlotSubTitle.Visible  = 0;
    pw.HighQualityRendering  = 1;
    pw.Legend.Visible        = 0;
    pw.BackgroundColor       = ColorTools.Black;
    pw.InterlacedDirection   = 1;
    pw.PlotAreaColor         = ColorTools.RGB(0,0,0);
    pw.InterlacedColor       = ColorTools.DarkGray;
    pw.PlotTitle.Color       = ColorTools.White;
 
    pw.XAxis.Title.Visible   = 1;
    pw.XAxis.Title.Font.Bold = 1;
    pw.YAxis.Title.Visible   = 1;
    pw.YAxis.Title.Font.Bold = 1;
 
    pw.XAxis.LabelsColor     = ColorTools.White;
    pw.YAxis.LabelsColor     = ColorTools.White;
    pw.XAxis.Title.Color     = ColorTools.White;
    pw.YAxis.Title.Color     = ColorTools.White;
    pw.XAxis.GridColor       = ColorTools.White;
    pw.YAxis.GridLineWidth   = 2;
 
EndProcedure;
 
// ----------------------------------------------------------------------------
// Configure plot series appearance
// ----------------------------------------------------------------------------
 
Define Procedure ConfigurePlotSeries(List<PlotScatterSeries> pssList);
 
    Variable i;
 
    For i = 0 to pssList.Count - 1;
        pssList[i].LineVisible    = 1;
        pssList[i].LineWidth      = 1;
        pssList[i].MarkersVisible = 0;
        pssList[i].MarkersSize    = 4;
    End;
 
EndProcedure;
 
// ----------------------------------------------------------------------------
// Vehicle view configuration
// ----------------------------------------------------------------------------
 
Define Procedure ConfigureVehicleViewCommon(ViewWindow vehicleView, Spacecraft source);
 
    vehicleView.WindowTitle = "Vehicle View";
 
    Alias tdvVehicle = vehicleView.Viewpoints[0].ThreeDView;
    tdvVehicle.Source         = source.ObjectId;
    tdvVehicle.Target         = source.ObjectId;
    tdvVehicle.ReferenceFrame = "inertial";
 
EndProcedure;
 
// ----------------------------------------------------------------------------
// Orbit view configuration
// ----------------------------------------------------------------------------
 
Define Procedure ConfigureOrbitViewCommon(
    ViewWindow orbitView,
    Spacecraft source,
    GroundStation gs0,
    GroundStation gs1,
    GroundStation gs2);
 
    orbitView.WindowTitle    = "Orbit View";
    orbitView.ShowStatusText = 0;
 
    orbitView.AddObject(gs0);
    orbitView.AddObject(gs1);
    orbitView.AddObject(gs2);
 
    orbitView.SetShowName(source.ObjectId, 1);
 
EndProcedure;
 
// ----------------------------------------------------------------------------
// Vehicle view for inspection satellite
// ----------------------------------------------------------------------------
 
Define Procedure ConfigureVehicleViewInspection(
    ViewWindow vehicleView,
    Spacecraft source,
    List<GroundStation> gsList);
 
    Call ConfigureVehicleViewCommon(vehicleView, source);
 
    Alias tdvVI = vehicleView.Viewpoints[0].ThreeDView;
    tdvVI.Declination    = -20;
    tdvVI.RightAscension = 7;
    tdvVI.Radius         = 25;
 
    vehicleView.SetHistoryMode(source.ObjectId, 1);
 
EndProcedure;
 
// ----------------------------------------------------------------------------
// Generic spacecraft positioning (kept for compatibility)
// ----------------------------------------------------------------------------
 
Define Procedure PositionSpacecraft(
    Spacecraft target,
    TimeSpan time,
    Array inputs,
    Variable stepMode);
 
    If (stepMode == STEP_MODE_STEP);
        Step target;
    ElseIf (stepMode == STEP_MODE_STEP_TO);
        If (inputs.Dimension != 1);
            Report "Input array must have a dimension of 1.";
            Stop;
        End;
        Step target to (target.Epoch == time);
    ElseIf (stepMode == STEP_MODE_SET_STATE);
        If (inputs.Dimension != 6);
            Report "Input array must have a dimension of 6.";
            Stop;
        End;
        target.Epoch    = time;
        target.Position = inputs[0:2];
        target.Velocity = inputs[3:5];
    Else;
        Report "Unrecognized step mode.";
        Stop;
    End;
 
EndProcedure;
 
// ----------------------------------------------------------------------------
// Solar-Orbiter-like heliocentric orbit for ODIN
// ----------------------------------------------------------------------------
 
Define Procedure SetInspectionSatelliteOrbit(Spacecraft sc);
 
    sc.CentralBody = "Sun";
    sc.SetPropagatorType(TypeOf(TwoBody));
    sc.Propagator.StepSize = TIMESPAN(1 hours);
 
    sc.Epoch = "Oct 01 2026 00:00:00.000000000".ParseCalendarDate();
 
    sc.A    = 8.931869393757236E+07;
    sc.E    = 5.073072340103084E-01;
    sc.I    = 1.261757932883799E+01;
    sc.RAAN = 3.223469465453840E+02;
    sc.W    = 3.063934436703851E+02;
    sc.TA   = 1.416090814160359E+02;
 
EndProcedure;

// ----------------------------------------------------------------------------
// Solar-Orbiter orbit
// ----------------------------------------------------------------------------
 
Define Procedure SetSolarOrbiterOrbit(Spacecraft sc);
 
    sc.CentralBody = "Sun";
    sc.SetPropagatorType(TypeOf(TwoBody));
    sc.Propagator.StepSize = TIMESPAN(1 hours);
 
    sc.Epoch = "Oct 01 2026 00:00:00.000000000".ParseCalendarDate();
 
    // Solar Orbiter co-orbits with ODIN (CDR: ODIN trails SolO ~20 km along-track).
    // Elements = ODIN's (CDR Table 6.1); tiny +TA lead puts SolO ~20 km ahead.
    sc.A    = 8.931869393757236E+07;
    sc.E    = 5.073072340103084E-01;
    sc.I    = 1.261757932883799E+01;
    sc.RAAN = 3.223469465453840E+02;
    sc.W    = 3.063934436703851E+02;
    sc.TA   = 1.416090814160359E+02 + 1.04E-05;   // +~20 km along-track lead
 
EndProcedure;
// ============================================================================
// FREEFORM 4 — Create Visibility Segment
// ============================================================================
 
gsTargets[0] = Cebreros;
gsTargets[1] = Malargue;
gsTargets[2] = New_Norcia;
 
visSeg.AddOccultingBody(Earth);
visSeg.AddOccultingBody(Sun);
 
visSeg.CelestialObjectOccultationModel = 1;
 
visSeg.SetTarget(ODIN);
visSeg.SetObserver(Malargue);
// ============================================================================
// FREEFORM 5 — Load and View Antenna Gain
// ============================================================================
 
RFTargetAntenna.BodyScale = 50;
 
antennaModelGo.SetReferenceObject(RFTargetAntenna.ObjectId);
 
currentVp.ViewpointName = 'Antenna Model View';
tdv.Source = RFTargetAntenna.ObjectId;
tdv.Target = RFTargetAntenna.ObjectId;
tdv.Radius = 5;
 
OutputLayout.SetWindowFrameVisibility({antennaGainView.ID}, 0);
OutputLayout.ApplyUpdates();
antennaGainView.ShowStatusText = 0;
 
RFLink1.Receiver.SetReferenceObject(RFTargetAntenna);
RFLink1.Receiver.LoadAntennaGainFile(AntennaPatternFilename);
RFLink1.Receiver.BuildAntennaGainGraphicsOverlay(antennaModelGo, 1, 1);
Update antennaGainView;
 
 
Variable animI = 0;
 
If (animateGainView);
    While (animI <= 2000);
        tdv.RightAscension = (tdv.RightAscension + 0.1) % 360;
        Update antennaGainView;
        animI++;
    End;
End;
 
Pause 2;
antennaGainView.CloseWindow();
 
Report "Antenna gain pattern loaded and visualized." to Console;
Report "" to Console;

// ============================================================================
// FREEFORM 6 — Plot and ViewWindow Definitions
// ============================================================================
 
vehicleView.SetTailLength(ODIN.ObjectId, 0);
 
// ----------------------------------------------------------------------------
// Plot series labels
// ----------------------------------------------------------------------------
 
powerToTargetData[0].Label = "Cebreros";
powerToTargetData[1].Label = "Malargue";
powerToTargetData[2].Label = "New Norcia";
 
signalToNoiseData[0].Label = "Cebreros";
signalToNoiseData[1].Label = "Malargue";
signalToNoiseData[2].Label = "New Norcia";
 
RFLinkMargin[0].Label = "Cebreros Link Margin";
RFLinkMargin[1].Label = "Malargue Link Margin";
RFLinkMargin[2].Label = "New Norcia Link Margin";

dataRateData[0].Label = "Cebreros";
dataRateData[1].Label = "Malargue";
dataRateData[2].Label = "New Norcia";

Call ConfigurePlotSeries(powerToTargetData);
Call ConfigurePlotSeries(signalToNoiseData);
Call ConfigurePlotSeries(RFLinkMargin);
Call ConfigurePlotSeries(dataRateData);
 
// ----------------------------------------------------------------------------
// Plot series colors and widths
// ----------------------------------------------------------------------------
 
powerToTargetData[0].LineColor = gsColor_1;
powerToTargetData[1].LineColor = gsColor_2;
powerToTargetData[2].LineColor = gsColor_3;
 
signalToNoiseData[0].LineColor = gsColor_1;
signalToNoiseData[1].LineColor = gsColor_2;
signalToNoiseData[2].LineColor = gsColor_3;
 
RFLinkMargin[0].LineColor = gsColor_1;
RFLinkMargin[1].LineColor = gsColor_2;
RFLinkMargin[2].LineColor = gsColor_3;

dataRateData[0].LineColor = gsColor_1;
dataRateData[1].LineColor = gsColor_2;
dataRateData[2].LineColor = gsColor_3;
 
// ----------------------------------------------------------------------------
// Configure Downlink Power plot
// ----------------------------------------------------------------------------
 
Call ConfigurePlotWindow(powerPlot);
 
powerPlot.Legend.Visible         = 1;
powerPlot.Legend.BackgroundColor = ColorTools.Black;
powerPlot.Legend.TextColor       = ColorTools.WhiteSmoke;
powerPlot.WindowTitle            = "Downlink Power";
powerPlot.PlotTitle.Text         = "HGA Downlink Received Power (MODE 2 only)";
powerPlot.YAxis.Title.Text       = "Received Power [dBW]";
powerPlot.XAxis.Title.Text       = "Mission Elapsed Time [days]";
powerPlot.YAxis.Scaling          = 0;
 
powerPlot.AddSeries(powerToTargetData[0]);
powerPlot.AddSeries(powerToTargetData[1]);
powerPlot.AddSeries(powerToTargetData[2]);
 
// ----------------------------------------------------------------------------
// Configure Carrier-to-Noise plot
// ----------------------------------------------------------------------------
 
Call ConfigurePlotWindow(signalToNoisePlot);
 
signalToNoisePlot.Legend.Visible         = 1;
signalToNoisePlot.Legend.BackgroundColor = ColorTools.Black;
signalToNoisePlot.Legend.TextColor       = ColorTools.WhiteSmoke;
signalToNoisePlot.WindowTitle            = "Downlink C/N";
signalToNoisePlot.PlotTitle.Text         = "HGA Downlink Carrier-to-Noise";
signalToNoisePlot.YAxis.Title.Text       = "Carrier-to-Noise [dB]";
signalToNoisePlot.XAxis.Title.Text       = "Mission Elapsed Time [days]";
signalToNoisePlot.YAxis.Scaling          = 0;
 
// FIX: AddSeries() calls were missing.
signalToNoisePlot.AddSeries(signalToNoiseData[0]);
signalToNoisePlot.AddSeries(signalToNoiseData[1]);
signalToNoisePlot.AddSeries(signalToNoiseData[2]);
 
// ----------------------------------------------------------------------------
// Configure RF Link Margin plot
// ----------------------------------------------------------------------------
 
Call ConfigurePlotWindow(rfLinkPlot);
 
rfLinkPlot.Legend.Visible         = 1;
rfLinkPlot.Legend.BackgroundColor = ColorTools.Black;
rfLinkPlot.Legend.TextColor       = ColorTools.WhiteSmoke;
rfLinkPlot.Legend.Font.Size       = 7.5;
rfLinkPlot.WindowTitle            = "RF Link Margin";
rfLinkPlot.PlotTitle.Text         = "RF Link Margin — ODIN Downlink (MODE 2 Only)";
rfLinkPlot.YAxis.Title.Text       = "Link Margin [dB]";
rfLinkPlot.XAxis.Title.Text       = "Mission Elapsed Time [days]";
rfLinkPlot.YAxis.Scaling          = 0;
 
// FIX: AddSeries() calls were missing.
rfLinkPlot.AddSeries(RFLinkMargin[0]);
rfLinkPlot.AddSeries(RFLinkMargin[1]);
rfLinkPlot.AddSeries(RFLinkMargin[2]);

// ----------------------------------------------------------------------------
// Configure Adaptive Data Rate plot (CDR deliverable: rate vs range/time)
// ----------------------------------------------------------------------------

Call ConfigurePlotWindow(dataRatePlot);

dataRatePlot.Legend.Visible         = 1;
dataRatePlot.Legend.BackgroundColor = ColorTools.Black;
dataRatePlot.Legend.TextColor       = ColorTools.WhiteSmoke;
dataRatePlot.WindowTitle            = "Downlink Data Rate";
dataRatePlot.PlotTitle.Text         = "Adaptive Downlink Data Rate (holds 6 dB floor, 89 kbps cap)";
dataRatePlot.YAxis.Title.Text       = "Data Rate [kbps]";
dataRatePlot.XAxis.Title.Text       = "Mission Elapsed Time [days]";
dataRatePlot.YAxis.Scaling          = 0;

dataRatePlot.AddSeries(dataRateData[0]);
dataRatePlot.AddSeries(dataRateData[1]);
dataRatePlot.AddSeries(dataRateData[2]);
 
// ----------------------------------------------------------------------------
// Epoch Window Overlay
// ----------------------------------------------------------------------------
 
epochWo.RemoveAllShapes();
 
epochWo.AddShape();
epochWo.Shapes[0].SetPosition(0, 0, 0.80);
epochWo.Shapes[0].TextOptions.TextColor = ColorTools.White;
epochWo.Shapes[0].TextOptions.Font.Bold = 1;
epochWo.Shapes[0].Visible = 1;
 
epochWo.AddShape();
epochWo.Shapes[1].SetPosition(0, 0.1, 0.86);
epochWo.Shapes[1].TextOptions.TextColor = ColorTools.White;
epochWo.Shapes[1].TextOptions.Font.Bold = 1;
epochWo.Shapes[1].Visible = 1;
 
// Mode overlay — shows current mode in orbit view
modeWo.RemoveAllShapes();
modeWo.AddShape();
modeWo.Shapes[0].SetPosition(0, 0, 0.93);
modeWo.Shapes[0].TextOptions.TextColor = ColorTools.Lime;
modeWo.Shapes[0].TextOptions.Font.Bold = 1;
modeWo.Shapes[0].Visible = 1;
 
orbitView.AddObject(epochWo);
orbitView.AddObject(modeWo);
 
// ----------------------------------------------------------------------------
// Window Frame Overlay
// ----------------------------------------------------------------------------
 
woWindowFrame.RemoveAllShapes();
woWindowFrame.AddShape();
woWindowFrame.Shapes[0].Type = "Rectangle";
woWindowFrame.Shapes[0].SetSize(0, 1, 1);
woWindowFrame.Shapes[0].RectangleOptions.FillOpacity = 0;
woWindowFrame.Shapes[0].RectangleOptions.BorderColor = ColorTools.White;
woWindowFrame.Shapes[0].RectangleOptions.SetCornerRadius(0, 0);
 
vehicleView.AddObject(woWindowFrame);
orbitView.AddObject(woWindowFrame);
 
// ----------------------------------------------------------------------------
// Ground station colors
// ----------------------------------------------------------------------------
 
Cebreros.DisplayName   = "Cebreros";
Malargue.DisplayName   = "Malargue";
New_Norcia.DisplayName = "New Norcia";
SolarOrbiter.DisplayName = "Solar Orbiter";
 
Cebreros.Color   = gsColor_1;
Malargue.Color   = gsColor_2;
New_Norcia.Color = gsColor_3;
SolarOrbiter.Color = soColor;
 
// ----------------------------------------------------------------------------
// View window setup
// ----------------------------------------------------------------------------
 
Call ConfigureVehicleViewInspection(vehicleView, ODIN, gsTargets);
Call ConfigureOrbitViewCommon(orbitView, ODIN, gsTargets[0], gsTargets[1], gsTargets[2]);
 
// Orbit view perspective
// FIX: Target set to Sun (not Earth) — ODIN is in a heliocentric orbit.
orbitView.Viewpoints[0].ThreeDView.Source         = ODIN.ObjectId;
orbitView.Viewpoints[0].ThreeDView.Target         = Sun.ObjectId;
orbitView.Viewpoints[0].ThreeDView.ReferenceFrame = "inertial";
orbitView.Viewpoints[0].ThreeDView.Declination    = 20;
orbitView.Viewpoints[0].ThreeDView.RightAscension = 270;
orbitView.Viewpoints[0].ThreeDView.Radius         = 300000;
 
//orbitView.AddObject(SolarOrbiter);
orbitView.SetShowName(SolarOrbiter.ObjectId, 1);
orbitView.SetHistoryMode(ODIN.ObjectId, 1);
orbitView.SetHistoryMode(SolarOrbiter.ObjectId, 1);
orbitView.SetShowName(ODIN.ObjectId, 1);
 
// ----------------------------------------------------------------------------
// Window sizes and positions
// ----------------------------------------------------------------------------
 
OutputLayout.SetWindowSize(powerPlot.ID,         1, 0.5, 1, 0.25);
OutputLayout.SetWindowSize(signalToNoisePlot.ID, 1, 0.5, 1, 0.25);
OutputLayout.SetWindowSize(rfLinkPlot.ID,        1, 0.5, 1, 0.25);
OutputLayout.SetWindowSize(dataRatePlot.ID,      1, 0.5, 1, 0.25);
OutputLayout.SetWindowSize(vehicleView.ID,       1, 0.5, 1, 0.5);
OutputLayout.SetWindowSize(orbitView.ID,         1, 0.5, 1, 0.5);
 
OutputLayout.SetWindowPosition(powerPlot.ID,         1, 0.5, 1, 0);
OutputLayout.SetWindowPosition(signalToNoisePlot.ID, 1, 0.5, 1, 0.25);
OutputLayout.SetWindowPosition(rfLinkPlot.ID,        1, 0.5, 1, 0.5);
OutputLayout.SetWindowPosition(dataRatePlot.ID,      1, 0.5, 1, 0.75);
OutputLayout.SetWindowPosition(vehicleView.ID,       1, 0,   1, 0);
OutputLayout.SetWindowPosition(orbitView.ID,         1, 0,   1, 0.5);
 
OutputLayout.SetWindowFrameVisibility(
    {powerPlot.ID, signalToNoisePlot.ID, vehicleView.ID, orbitView.ID, rfLinkPlot.ID, dataRatePlot.ID}, 0);
 
vehicleView.ShowStatusText = 0;
orbitView.ShowStatusText   = 0;
 
OutputLayout.ApplyUpdates();
//Block

   // ============================================================================
   // FREEFORM 7 (inside Block) — Set Simulation Mode
   // ============================================================================
    
   SimMode           = SIM_MODE_SC_TO_GS;
   UseEphemerisForSource = 0;
   calcDownLink      = 1;
   
   currentMode = MODE_LGA_TTC;
   
   Report "Simulation mode: spacecraft-to-ground-station." to Console;
   Report "Initial operating mode: LGA TT&C (MODE 0)." to Console;
   Report "" to Console;
    
   // ============================================================================
   // FREEFORM 8 (inside Block) — Simulation Setup
   // ============================================================================
    
   gsTargets[0] = Cebreros;
   gsTargets[1] = Malargue;
   gsTargets[2] = New_Norcia;
    
   Cebreros.DisplayName   = "Cebreros";
   Malargue.DisplayName   = "Malargue";
   New_Norcia.DisplayName = "New Norcia";
   SolarOrbiter.DisplayName = "Solar Orbiter";
    
   Cebreros.Color   = gsColor_1;
   Malargue.Color   = gsColor_2;
   New_Norcia.Color = gsColor_3;
   SolarOrbiter.Color = soColor;
    
   // Configure ODIN as inspection satellite source
   Call ConfigureSource(ODIN, csSource);
   ODIN.DisplayName = "ODIN";
    
   Call ConfigureInspectionDownlink(RFLink1, ODIN, Malargue, AntennaPatternFilename);
   
    
   // RF link vector (orange)
   commVector.Color       = ColorTools.Orange;
   commVector.DisplayName = "RF Link Vector";
   commVector.BuildVector(13, RFLink1);
    
   // Velocity vector
   velVector.DrawMethod   = 1;
   velVector.Color        = ColorTools.Yellow;
   velVector.DisplayName  = "Velocity Vector";
   velVector.BuildVector(7, ODIN);
    
   // Angular momentum vector
   angVector.Color        = ColorTools.Cyan;
   angVector.DisplayName  = "Angular Momentum";
   angVector.BuildVector(5, ODIN);
    
   // Transmitter antenna graphic overlay
   transmitterGo.SetReferenceObject(ODIN.Sensors[0].ObjectId);
    
   // Load antenna pattern on transmitter for visualization
   RFLink1.Transmitter.LoadAntennaGainFile(AntennaPatternFilename);
   RFLink1.Transmitter.BuildAntennaGainGraphicsOverlay(transmitterGo, 5, 1);
    
   // Initialize ODIN orbit
   If (UseEphemerisForSource);
       ODIN.SetPropagatorType(TypeOf(Ephemeris));
       Alias ephInspection = (ODIN.Propagator AsType Ephemeris);
       ephInspection.LoadEphemeris(VehicleEphemerisFilename);
   Else;
       Call SetInspectionSatelliteOrbit(ODIN);
   End;
   
   // Solar Orbiter co-orbits with ODIN (CDR Table 6.1, TwoBody) — ~20 km trailing.
   // Without this call SolO ran on its XML force model and drifted ~38 Mkm over 1500 d.
   Call SetSolarOrbiterOrbit(SolarOrbiter);
   
   // Save initial epoch and initialize vectors
   initialEpoch    = ODIN.Epoch;
   velVector.Epoch = ODIN.Epoch;
   angVector.Epoch = ODIN.Epoch;
    
   csSource.BuildCoordinateSystem(1, velVector, 2, angVector);
    
   // Velocity label overlay
   velocityGo.SetReferenceObject(ODIN.ObjectId);
   velocityGo.ShapeType = "Annotations";
   velocityGo.ClearOverlayElements();
   velocityGo.DefaultColor = ColorTools.Yellow;
   velocityGo.AddOverlayElement(7.5, 0, 0, "Velocity Vector");
   vehicleView.AddObject(velocityGo);
    
   // Vehicle view perspective
   vehicleView.Viewpoints[0].ThreeDView.Source         = ODIN.ObjectId;
   vehicleView.Viewpoints[0].ThreeDView.Target         = ODIN.ObjectId;
   vehicleView.Viewpoints[0].ThreeDView.ReferenceFrame = "inertial";
   vehicleView.Viewpoints[0].ThreeDView.Declination    = -20;
   vehicleView.Viewpoints[0].ThreeDView.RightAscension = 7;
   vehicleView.Viewpoints[0].ThreeDView.Radius         = 25;
   vehicleView.SetHistoryMode(ODIN.ObjectId, 1);
   vehicleView.SetShowName(ODIN.ObjectId, 1);
    
   // Orbit view perspective
   // FIX: Target = Sun for heliocentric view. Radius increased to show full orbit.
   orbitView.Viewpoints[0].ThreeDView.Source         = ODIN.ObjectId;
   orbitView.Viewpoints[0].ThreeDView.Target         = Sun.ObjectId;
   orbitView.Viewpoints[0].ThreeDView.ReferenceFrame = "inertial";
   orbitView.Viewpoints[0].ThreeDView.Declination    = 20;
   orbitView.Viewpoints[0].ThreeDView.RightAscension = 270;
   orbitView.Viewpoints[0].ThreeDView.Radius         = 300000;
   orbitView.SetHistoryMode(ODIN.ObjectId, 1);
   orbitView.SetHistoryMode(SolarOrbiter.ObjectId, 1);
   orbitView.SetShowName(ODIN.ObjectId, 1);
   orbitView.SetShowName(SolarOrbiter.ObjectId, 1);
    
   Report "Simulation setup complete." to Console;
   Report "ODIN and Solar Orbiter orbits initialized." to Console;
   Report "" to Console;
    
   Update vehicleView;
   Update orbitView;
   OutputLayout.ApplyUpdates();
    
    
//EndBlock

// ============================================================================
// FREEFORM 9 — Propagation (FreeForm 11 in Mission Sequence)
// ============================================================================
 
gsTargets[0] = Cebreros;
gsTargets[1] = Malargue;
gsTargets[2] = New_Norcia;
 
// ----------------------------------------------------------------------------
// Visibility segment target
// ----------------------------------------------------------------------------
 
visSeg.SetTarget(ODIN);
visSeg.SetObserver(gsTargets[0]);
 
// ----------------------------------------------------------------------------
// Timing initialization
// ----------------------------------------------------------------------------
 
initialEpoch = ODIN.Epoch;
 
ODIN.Propagator.StepSize = TIMESPAN(1 hours);
SolarOrbiter.Propagator.StepSize = TIMESPAN(1 hours);
 
elapsedDays        = 0;
daysSinceStart     = 0;
lbValidPointCount  = 0;
lbViewCounter      = 0;
onboardDataGB      = 0.0;
currentMode        = MODE_LGA_TTC; 

// ----------------------------------------------------------------------------
// Precompute link budget constants
// ----------------------------------------------------------------------------
 
lbWavelengthM    = 0.299792458 / lbFrequencyGHz;
lbTxPowerdBW     = 10 * log(lbTxPowerW);
lbTxGaindBi      = 10 * log(lbTxEfficiency * (lbPi * lbTxAntennaDiamM / lbWavelengthM)^2);
lbRxGaindBi      = 10 * log(lbRxEfficiency * (lbPi * lbRxAntennaDiamM / lbWavelengthM)^2);
lbEIRPdBW        = lbTxPowerdBW + lbTxGaindBi - lbTxLineLossdB;
lbNoDensitydBWHZ = lbBoltzmannDB + 10 * log(lbSystemNoiseTempK);
lbNoisePowerdBW  = lbNoDensitydBWHZ + 10 * log(lbBandwidthHz);
 
// Console sanity check
Report "" to Console;
Report "Link budget constants:" to Console;
Report "  Tx Power [dBW]      : ", lbTxPowerdBW     to Console;
Report "  Tx Gain [dBi]       : ", lbTxGaindBi      to Console;
Report "  Rx Gain [dBi]       : ", lbRxGaindBi      to Console;
Report "  EIRP [dBW]          : ", lbEIRPdBW        to Console;
Report "  No density [dBW/Hz] : ", lbNoDensitydBWHZ to Console;
Report "  Req. Eb/N0 [dB]     : ", lbRequiredEbNodB to Console;
Report "" to Console;
Report "Starting 1500-day multi-mode propagation..." to Console;
Report "" to Console;
 
// ============================================================================
// MAIN PROPAGATION LOOP
// ============================================================================
 
While (ODIN.ElapsedTimeFromEpoch(initialEpoch) < TIMESPAN(1500 days));
 
    Step ODIN;
	Step SolarOrbiter to (SolarOrbiter.Epoch == ODIN.Epoch);
 
    elapsedDays = ODIN.ElapsedTimeFromEpoch(initialEpoch).ToMinutes() / 1440.0;
	
	daysSinceStart = ODIN.ElapsedTimeFromEpoch(initialEpoch).ToDays();
 
    // ------------------------------------------------------------------------
    // Update epoch overlay
    // ------------------------------------------------------------------------
 
    epochWo.Shapes[0].TextOptions.Text = StringConcat(
        "Epoch: ", ODIN.Epoch.ConvertToCalendarDate("Mmm D YYYY"));
    epochWo.Shapes[1].TextOptions.Text = StringConcat(
        ODIN.Epoch.ConvertToCalendarDate("hh:mm:ss"), " UTC");
 
    // ------------------------------------------------------------------------
    // Update vectors and attitude
    // ------------------------------------------------------------------------
 
    velVector.Epoch = ODIN.Epoch;
    angVector.Epoch = ODIN.Epoch;
    csSource.Epoch  = ODIN.Epoch;
    ODIN.SetOrientation(csSource);
 
    // ------------------------------------------------------------------------
    // Downlink windows are no longer hardcoded by mission day. Availability is
    // now decided from real geometry (ODIN-Earth range + Sun occultation) in the
    // link-evaluation block below. The old day-based windows assumed heliocentric
    // distance as a proxy for link difficulty, which is invalid for a deep-space
    // orbit (Sun distance != Earth distance).
    // ------------------------------------------------------------------------

    isInDownlinkWindow = 0;
	
	// ------------------------------------------------------------------------
    // Inspection windows (CDR): Insp 1 = Feb 8-22 2028 (days 495-509),
    //                           Insp 2 = Nov 21-Dec 6 2028 (days 782-797).
    // (Windows 3-4 disabled — CDR defines only two inspection campaigns.)
    // ------------------------------------------------------------------------
 
	isInInspectionWindow = 0;
 
    If (daysSinceStart >= 495.0 and daysSinceStart <= 509.0);   
    	isInInspectionWindow = 1; 
    End;
	
    If (daysSinceStart >= 782.0 and daysSinceStart <= 797.0);  
    	isInInspectionWindow = 1; 
    End;
	
    If (0 == 1 /* disabled: CDR has only two inspection campaigns */ and daysSinceStart <= 802.0);  
    	isInInspectionWindow = 1;
    End;
	
    If (0 == 1 /* disabled: CDR has only two inspection campaigns */ and daysSinceStart <= 1104.0); 
    	isInInspectionWindow = 1; 
    End;	
	
	odinToSORange = ODIN.Range(SolarOrbiter);
	earthRangeKm  = ODIN.Range(Earth);
	earthRangeAU  = earthRangeKm / AU_KM;
 
	// Mode pre-decision: safe LGA TT&C by default; INSPECTION when near Solar
	// Orbiter during a scheduled encounter window. HGA downlink is decided AFTER
	// the link budget is evaluated below (geometry-driven, not by calendar date).
	currentMode = MODE_LGA_TTC;
	If (isInInspectionWindow and odinToSORange < inspectionThresholdKm);
		currentMode = MODE_INSPECTION;
	End;
	
	// Throttled console mode report (every 240 steps = every 10 days)
    modeReportCounter++;
    If (modeReportCounter >= 240);
        Report "Day ", elapsedDays, "  Mode: ", currentMode,
               "  Earth [AU]: ", earthRangeAU,
               "  SO Range [km]: ", odinToSORange,
               "  SSM [GB]: ", onboardDataGB to Console;
        modeReportCounter = 0;
    End;
	
	// ------------------------------------------------------------------------
    // Data volume model 
	// Imaging only in MODE 1. Downlink drain only in MODE 2.
    // ------------------------------------------------------------------------
 
    If (currentMode == MODE_INSPECTION);
        onboardDataGB = onboardDataGB + imagingRateGBperHour;
        If (onboardDataGB > storageCapacityGB);
            onboardDataGB = storageCapacityGB;
        End;
    End;
	
    // ------------------------------------------------------------------------
    // Select best visible ground station (MODE 2 Only)_
    // ------------------------------------------------------------------------
 
	// Evaluate the downlink budget EVERY step so availability is geometry-driven.
	// visSeg already occults on Earth's limb (target station on the far side) and
	// on the Sun (solar conjunction), matching ODIN's steerable-HGA constraint.
	If (1 == 1);

	    bestLinkMargin   = -1.0e15;
	    bestStationIndex = -1;
	    bestReceivedPower = -1.0e15;
	    bestCtoN         = -1.0e15;
	    bestRangeKm      = -1;
 
	    For gsToUse = 0 to 2;
	 
	        visSeg.SetObserver(gsTargets[gsToUse]);
	        inView = visSeg.Visibility(ODIN.Epoch);
	 
	        If (inView);
	 
	            lbRangeKm = ODIN.Range(gsTargets[gsToUse]);
	 
	            If (lbRangeKm > 0);
	 
	                lbFreeSpaceLossdB = 92.45
	                                  + 20 * log(lbRangeKm)
	                                  + 20 * log(lbFrequencyGHz);
	 
	                lbTotalLossdB = lbFreeSpaceLossdB
	                              + lbPointingLossdB
	                              + lbPolarizationLossdB
	                              + lbAtmosphericLossdB;
	 
	                // Received carrier power [dBW]
	                recPr = lbEIRPdBW + lbRxGaindBi - lbTotalLossdB;
	 
	                // Carrier-to-noise ratio over bandwidth [dB]
	                recCtoN = recPr - lbNoisePowerdBW;
	 
	                // Eb/N0 [dB]
	                lbEbNodB = recPr - lbNoDensitydBWHZ - 10 * log(lbDataRateHz);
	 
	                // RF link margin [dB]
	                linkMargin = lbEbNodB - lbRequiredEbNodB - lbImplementationLossdB;
	 
	                If (linkMargin > bestLinkMargin);
	                    bestLinkMargin    = linkMargin;
	                    bestStationIndex  = gsToUse;
	                    bestReceivedPower = recPr;
	                    bestCtoN          = recCtoN;
	                    bestRangeKm       = lbRangeKm;
	                End;
	 
	            End;
	 
	        End;
	 
	    End;
		
    // ------------------------------------------------------------------------
    // Plot — only during downlink windows when a station is visible
    // ------------------------------------------------------------------------
 
    // Promote to HGA downlink when the link closes with margin AND data is queued.
    // (Link "closes" = a station is visible past Earth/Sun occultation and the
    //  computed margin clears the operational threshold.)
    // Adaptive data rate: highest rate that still holds the 6 dB margin floor at
    // the best station, capped at the CDR peak (89 kbps). This is the CDR model —
    // rate is chosen per geometry to hold margin, not fixed.
    lbAchievableRateHz = 0.0;
    If (bestStationIndex >= 0);
        lbAchievableRateHz = 10^((bestReceivedPower - lbNoDensitydBWHZ
                                  - lbRequiredEbNodB - lbImplementationLossdB
                                  - downlinkMarginThresholdDB) / 10);
        If (lbAchievableRateHz > lbMaxDataRateHz);
            lbAchievableRateHz = lbMaxDataRateHz;
        End;
    End;

    downlinkAvailable = 0;
    If (bestStationIndex >= 0 and lbAchievableRateHz >= lbMinUsefulRateHz);
        downlinkAvailable = 1;
    End;
    If (currentMode == MODE_LGA_TTC and downlinkAvailable and onboardDataGB > 0);
        currentMode = MODE_HGA_DOWNLINK;
    End;

    If (bestStationIndex >= 0);

        pointIsReasonable = 1;
 
        If (bestReceivedPower < -300);  
        	pointIsReasonable = 0;  
        End;
    	
        If (bestReceivedPower > 100);   
        	pointIsReasonable = 0; 
        End;
    	
        If (bestCtoN < -300);           
        	pointIsReasonable = 0; 
        End;
    	
        If (bestCtoN > 300);           
        	pointIsReasonable = 0; 
        End;
    	
        If (bestLinkMargin < -300); 
        	pointIsReasonable = 0; 
        End;
    	
        If (bestLinkMargin > 300);   
        	pointIsReasonable = 0; 
        End;
 
        If (pointIsReasonable);
 
            powerToTargetData[bestStationIndex].AddPoints(elapsedDays, bestReceivedPower);
            signalToNoiseData[bestStationIndex].AddPoints(elapsedDays, bestCtoN);
            RFLinkMargin[bestStationIndex].AddPoints(elapsedDays, bestLinkMargin);
            dataRateData[bestStationIndex].AddPoints(elapsedDays, lbAchievableRateHz / 1000.0);
            lbValidPointCount++;

            // Drain onboard data buffer only while actively downlinking (MODE 2), at the
            // adaptive rate: GB/hour = rate[bps] * 3600 s / 8e9 (GB = 1e9 bytes).
            If (currentMode == MODE_HGA_DOWNLINK);
                onboardDataGB = onboardDataGB - lbAchievableRateHz * 3600.0 / 8.0e9;
                If (onboardDataGB < 0);
                    onboardDataGB = 0;
                End;
            End;
 
        End;
 
    End;

	End;
 
    // ------------------------------------------------------------------------
    // Animate views
    // ------------------------------------------------------------------------
 
    If (animateView);
 
        vehicleView.CurrentViewpoint.ThreeDView.RightAscension =
            (vehicleView.CurrentViewpoint.ThreeDView.RightAscension + 0.3) % 360;
 
        orbitView.CurrentViewpoint.ThreeDView.RightAscension =
            (orbitView.CurrentViewpoint.ThreeDView.RightAscension + 0.04) % 360;
 
    End;
 
    // ------------------------------------------------------------------------
    // Update plots every 2 days (48 x 1-hour steps)
    // ------------------------------------------------------------------------
 
    lbViewCounter++;
 
    If (lbViewCounter >= 48);
 
        Update powerPlot;
        Update signalToNoisePlot;
        Update rfLinkPlot;
        Update dataRatePlot;
        Update vehicleView;
        Update orbitView;
        lbViewCounter = 0;
 
    End;
	
	Update ViewWindow1;
 
End;
 
// ----------------------------------------------------------------------------
// Final updates
// ----------------------------------------------------------------------------
 
Update powerPlot;
Update signalToNoisePlot;
Update rfLinkPlot;
Update vehicleView;
Update orbitView;
 
// ----------------------------------------------------------------------------
// Final console report
// ----------------------------------------------------------------------------
 
Report "" to Console;
Report "ODIN 1500-day multi-mode propagation complete." to Console;
Report "" to Console;
Report "Valid HGA downlink samples : ", lbValidPointCount to Console;
Report "Remaining onboard data [GB]: ", onboardDataGB     to Console;
Report "" to Console;
Report "Final step values:" to Console;
Report "  Elapsed days        : ", elapsedDays       to Console;
Report "  Operating mode      : ", currentMode        to Console;
Report "  SO range [km]       : ", odinToSORange      to Console;
Report "  Selected GS index   : ", bestStationIndex   to Console;
Report "  Range to GS [km]    : ", bestRangeKm        to Console;
Report "  Received power [dBW]: ", bestReceivedPower  to Console;
Report "  C/N [dB]            : ", bestCtoN           to Console;
Report "  Link margin [dB]    : ", bestLinkMargin     to Console;
Report "  Adaptive rate [kbps]: ", lbAchievableRateHz / 1000.0 to Console;
Report "" to Console;
Report "Downlink availability is geometry-driven: a station is visible past" to Console;
Report "Earth-limb and Sun occultation AND the computed link margin clears the" to Console;
Report "6 dB CDR floor (SSR-COMM-03). It is no longer scheduled by mission day." to Console;
Report "Free-space path loss is set by the ODIN-Earth range (not the Sun range)." to Console;
Report "" to Console;
Report "NOTE: Solar Orbiter is modeled as a TwoBody co-orbit with ODIN" to Console;
Report "(CDR Table 6.1 elements, ~20 km trailing). Load a real SPICE/.e" to Console;
Report "ephemeris for higher-fidelity inspection proximity results." to Console;