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17 package org.orekit.estimation.measurements.modifiers;
18
19 import java.util.List;
20
21 import org.hipparchus.geometry.euclidean.threed.Vector3D;
22 import org.hipparchus.stat.descriptive.DescriptiveStatistics;
23 import org.junit.jupiter.api.Assertions;
24 import org.junit.jupiter.api.Test;
25 import org.orekit.attitudes.LofOffset;
26 import org.orekit.estimation.Context;
27 import org.orekit.estimation.EstimationTestUtils;
28 import org.orekit.estimation.measurements.EstimatedMeasurementBase;
29 import org.orekit.estimation.measurements.EstimationModifier;
30 import org.orekit.estimation.measurements.ObservedMeasurement;
31 import org.orekit.estimation.measurements.gnss.InterSatellitesPhase;
32 import org.orekit.estimation.measurements.gnss.InterSatellitesPhaseMeasurementCreator;
33 import org.orekit.frames.LOFType;
34 import org.orekit.gnss.PredefinedGnssSignal;
35 import org.orekit.gnss.RadioWave;
36 import org.orekit.orbits.CartesianOrbit;
37 import org.orekit.orbits.Orbit;
38 import org.orekit.orbits.OrbitType;
39 import org.orekit.orbits.PositionAngleType;
40 import org.orekit.propagation.BoundedPropagator;
41 import org.orekit.propagation.EphemerisGenerator;
42 import org.orekit.propagation.Propagator;
43 import org.orekit.propagation.SpacecraftState;
44 import org.orekit.propagation.conversion.NumericalPropagatorBuilder;
45 import org.orekit.utils.TimeStampedPVCoordinates;
46
47 public class ShapiroInterSatellitePhaseModifierTest {
48
49
50 private static final RadioWave RADIO_WAVE = PredefinedGnssSignal.G01;
51
52 @Test
53 public void testShapiroOneWay() {
54 doTestShapiro(0.000047764, 0.000086953, 0.000164659);
55 }
56
57 private void doTestShapiro(final double expectedMin, final double expectedMean, final double expectedMax) {
58
59 Context context = EstimationTestUtils.eccentricContext("regular-data:potential:tides");
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61 final NumericalPropagatorBuilder propagatorBuilder =
62 context.createBuilder(OrbitType.KEPLERIAN, PositionAngleType.TRUE, true,
63 1.0e-6, 60.0, 0.001);
64 propagatorBuilder.setAttitudeProvider(new LofOffset(propagatorBuilder.getFrame(), LOFType.LVLH));
65
66
67 final TimeStampedPVCoordinates original = context.initialOrbit.getPVCoordinates();
68 final Orbit closeOrbit = new CartesianOrbit(new TimeStampedPVCoordinates(context.initialOrbit.getDate(),
69 original.getPosition().add(new Vector3D(1000, 2000, 3000)),
70 original.getVelocity().add(new Vector3D(-0.03, 0.01, 0.02))),
71 context.initialOrbit.getFrame(),
72 context.initialOrbit.getMu());
73 final Propagator closePropagator = EstimationTestUtils.createPropagator(closeOrbit,
74 propagatorBuilder);
75 final EphemerisGenerator generator = closePropagator.getEphemerisGenerator();
76 closePropagator.propagate(context.initialOrbit.getDate().shiftedBy(3.5 * closeOrbit.getKeplerianPeriod()));
77 final BoundedPropagator ephemeris = generator.getGeneratedEphemeris();
78 final Propagator p1 = EstimationTestUtils.createPropagator(context.initialOrbit,
79 propagatorBuilder);
80 final int ambiguity = 1234;
81 final double localClockOffset = 0.137e-6;
82 final double remoteClockOffset = 469.0e-6;
83 List<ObservedMeasurement<?>> measurements =
84 EstimationTestUtils.createMeasurements(p1,
85 new InterSatellitesPhaseMeasurementCreator(ephemeris,
86 RADIO_WAVE,
87 ambiguity,
88 localClockOffset,
89 remoteClockOffset,
90 Vector3D.ZERO,
91 Vector3D.ZERO),
92 1.0, 3.0, 300.0);
93
94 final ShapiroInterSatellitePhaseModifier modifier = new ShapiroInterSatellitePhaseModifier(context.initialOrbit.getMu());
95 final Propagator p3 = EstimationTestUtils.createPropagator(context.initialOrbit,
96 propagatorBuilder);
97 DescriptiveStatistics stat = new DescriptiveStatistics();
98 for (int i = 0; i < measurements.size(); ++i) {
99 InterSatellitesPhase sr = (InterSatellitesPhase) measurements.get(i);
100 SpacecraftState[] states = new SpacecraftState[] {
101 p3.propagate(sr.getDate()),
102 ephemeris.propagate(sr.getDate())
103 };
104 EstimatedMeasurementBase<InterSatellitesPhase> evalNoMod = sr.estimateWithoutDerivatives(states);
105
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107 sr.addModifier(modifier);
108 boolean found = false;
109 for (final EstimationModifier<InterSatellitesPhase> existing : sr.getModifiers()) {
110 found = found || existing == modifier;
111 }
112 Assertions.assertTrue(found);
113 EstimatedMeasurementBase<InterSatellitesPhase> eval = sr.estimateWithoutDerivatives(states);
114
115 stat.addValue(eval.getEstimatedValue()[0] - evalNoMod.getEstimatedValue()[0]);
116 Assertions.assertEquals(1,
117 eval.getAppliedEffects().entrySet().stream().
118 filter(e -> e.getKey().getEffectName().equals("Shapiro")).count());
119 }
120
121
122 final double wavelength = ((InterSatellitesPhase) measurements.get(0)).getWavelength();
123
124 Assertions.assertEquals(expectedMin, stat.getMin() * wavelength, 1.0e-9);
125 Assertions.assertEquals(expectedMean, stat.getMean() * wavelength, 1.0e-9);
126 Assertions.assertEquals(expectedMax, stat.getMax() * wavelength, 1.0e-9);
127
128 }
129
130 }
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