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3    * contributor license agreements.  See the NOTICE file distributed with
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17  package org.orekit.estimation.measurements.modifiers;
18  
19  import org.hipparchus.geometry.euclidean.threed.Vector3D;
20  import org.junit.jupiter.api.Assertions;
21  import org.junit.jupiter.api.BeforeEach;
22  import org.junit.jupiter.api.Test;
23  import org.orekit.Utils;
24  import org.orekit.estimation.measurements.EstimatedMeasurement;
25  import org.orekit.estimation.measurements.EstimatedMeasurementBase;
26  import org.orekit.estimation.measurements.EstimationModifier;
27  import org.orekit.estimation.measurements.ObservableSatellite;
28  import org.orekit.estimation.measurements.gnss.OneWayGNSSRange;
29  import org.orekit.propagation.SpacecraftState;
30  import org.orekit.propagation.analytical.tle.TLE;
31  import org.orekit.propagation.analytical.tle.TLEPropagator;
32  import org.orekit.time.AbsoluteDate;
33  import org.orekit.time.TimeScalesFactory;
34  
35  public class RelativisticClockOneWayGNSSRangeModifierTest {
36  
37      /** Date. */
38      private static AbsoluteDate date;
39  
40      /** Spacecraft states. */
41      private static SpacecraftState[] states;
42  
43      @Test
44      public void testRelativisticClockCorrection() {
45  
46          // Measurement
47          final OneWayGNSSRange range = new OneWayGNSSRange(states[1].getOrbit(), 0.0, date,
48                                                            Vector3D.distance(states[0].getPosition(),
49                                                                              states[1].getPosition()),
50                                                            1.0, 1.0, new ObservableSatellite(0));
51  
52          // Inter-satellites range before applying the modifier
53          final EstimatedMeasurementBase<OneWayGNSSRange> estimatedBefore = range.estimateWithoutDerivatives(states);
54  
55          // Inter-satellites range before applying the modifier
56          final EstimationModifier<OneWayGNSSRange> modifier = new RelativisticClockOneWayGNSSRangeModifier();
57          range.addModifier(modifier);
58          final EstimatedMeasurement<OneWayGNSSRange> estimatedAfter = range.estimate(0, 0, states);
59  
60          // Verify
61          Assertions.assertEquals(-10.57, estimatedBefore.getEstimatedValue()[0] - estimatedAfter.getEstimatedValue()[0], 1.0e-2);
62          Assertions.assertEquals(0, modifier.getParametersDrivers().size());
63          Assertions.assertEquals(1,
64                                  estimatedAfter.getAppliedEffects().entrySet().stream().
65                                  filter(e -> e.getKey().getEffectName().equals("clock relativity")).count());
66  
67      }
68  
69      @BeforeEach
70      public void setUp() {
71          // Data root
72          Utils.setDataRoot("regular-data");
73  
74          // Date
75          date = new AbsoluteDate("2004-01-13T00:00:00.000", TimeScalesFactory.getUTC());
76  
77          // Spacecraft states
78          states = new SpacecraftState[2];
79          final TLE local = new TLE("1 27642U 03002A   04013.91734903  .00000108  00000-0  12227-4 0  3621",
80                                    "2 27642  93.9970   6.8623 0003169  80.1383 280.0205 14.90871424 54508");
81          final TLE remote = new TLE("1 20061U 89044A   04013.44391333  .00000095  00000-0  10000-3 0  3242",
82                                     "2 20061  53.4233 172.2072 0234017 261.4179  95.8975  2.00577231106949");
83          states[0] = TLEPropagator.selectExtrapolator(local).propagate(date);
84          states[1] = TLEPropagator.selectExtrapolator(remote).propagate(date);
85      }
86  
87  }