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3    * contributor license agreements.  See the NOTICE file distributed with
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5    * CS licenses this file to You under the Apache License, Version 2.0
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8    *
9    *   http://www.apache.org/licenses/LICENSE-2.0
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11   * Unless required by applicable law or agreed to in writing, software
12   * distributed under the License is distributed on an "AS IS" BASIS,
13   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14   * See the License for the specific language governing permissions and
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16   */
17  package org.orekit.estimation.measurements.modifiers;
18  
19  import java.util.Collections;
20  import java.util.List;
21  
22  import org.orekit.estimation.measurements.EstimatedMeasurementBase;
23  import org.orekit.estimation.measurements.EstimationModifier;
24  import org.orekit.estimation.measurements.Range;
25  import org.orekit.utils.Constants;
26  import org.orekit.utils.ParameterDriver;
27  
28  /** Class modifying theoretical range measurement with relativistic clock correction.
29   * <p>
30   * Relativistic clock correction is caused by the motion of the satellite as well as
31   * the change in the gravitational potential
32   * </p>
33   * @author Bryan Cazabonne
34   * @since 10.3
35   *
36   * @see "Teunissen, Peter, and Oliver Montenbruck, eds. Springer handbook of global navigation
37   * satellite systems. Chapter 19.2. Springer, 2017."
38   */
39  public class RelativisticClockRangeModifier extends AbstractRelativisticClockModifier implements EstimationModifier<Range> {
40  
41      /** Simple constructor. */
42      public RelativisticClockRangeModifier() {
43          super();
44      }
45  
46      /** {@inheritDoc} */
47      @Override
48      public List<ParameterDriver> getParametersDrivers() {
49          return Collections.emptyList();
50      }
51  
52      /** {@inheritDoc} */
53      @Override
54      public void modifyWithoutDerivatives(final EstimatedMeasurementBase<Range> estimated) {
55          // Relativistic effect
56          final double dtRel = relativisticCorrection(estimated);
57  
58          // Update estimated value taking into account the relativistic effect.
59          final double[] newValue = estimated.getEstimatedValue().clone();
60          newValue[0] = newValue[0] - dtRel * Constants.SPEED_OF_LIGHT;
61          estimated.modifyEstimatedValue(this, newValue);
62      }
63  
64  }