1   /* Copyright 2002-2025 CS GROUP
2    * Licensed to CS GROUP (CS) under one or more
3    * contributor license agreements.  See the NOTICE file distributed with
4    * this work for additional information regarding copyright ownership.
5    * CS licenses this file to You under the Apache License, Version 2.0
6    * (the "License"); you may not use this file except in compliance with
7    * the License.  You may obtain a copy of the License at
8    *
9    *   http://www.apache.org/licenses/LICENSE-2.0
10   *
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
15   * limitations under the License.
16   */
17  package org.orekit.estimation.measurements.modifiers;
18  
19  import java.util.Collections;
20  import java.util.List;
21  
22  import org.hipparchus.geometry.euclidean.threed.Vector3D;
23  import org.orekit.estimation.measurements.EstimatedMeasurementBase;
24  import org.orekit.estimation.measurements.EstimationModifier;
25  import org.orekit.estimation.measurements.InterSatellitesRange;
26  import org.orekit.gnss.antenna.FrequencyPattern;
27  import org.orekit.utils.ParameterDriver;
28  
29  /** On-board antenna offset effect on inter-satellites range measurements.
30   * @author Luc Maisonobe
31   * @since 9.0
32   */
33  public class OnBoardAntennaInterSatellitesRangeModifier
34      extends PhaseCentersInterSatellitesBaseModifier<InterSatellitesRange>
35      implements EstimationModifier<InterSatellitesRange> {
36  
37      /** Simple constructor.
38       * @param receiverPhaseCenter position of the Antenna Phase Center in emitter satellite frame
39       * @param emitterPhaseCenter position of the Antenna Phase Center in receiver satellite frame
40       */
41      public OnBoardAntennaInterSatellitesRangeModifier(final Vector3D receiverPhaseCenter,
42                                                        final Vector3D emitterPhaseCenter) {
43          this(new FrequencyPattern(receiverPhaseCenter, null),
44               new FrequencyPattern(emitterPhaseCenter, null));
45      }
46  
47      /** Simple constructor.
48       * @param receiverPattern pattern for receiver satellite
49       * @param emitterPattern  pattern for emitter satellite
50       * @since 12.1
51       */
52      public OnBoardAntennaInterSatellitesRangeModifier(final FrequencyPattern receiverPattern,
53                                                        final FrequencyPattern emitterPattern) {
54          super(receiverPattern, emitterPattern);
55      }
56  
57      /** {@inheritDoc} */
58      @Override
59      public List<ParameterDriver> getParametersDrivers() {
60          return Collections.emptyList();
61      }
62  
63      /** {@inheritDoc} */
64      @Override
65      public void modifyWithoutDerivatives(final EstimatedMeasurementBase<InterSatellitesRange> estimated) {
66          final double delta = estimated.getParticipants().length < 3 ?
67                               oneWayDistanceModification(estimated) :
68                               twoWayDistanceModification(estimated);
69          estimated.modifyEstimatedValue(this, estimated.getEstimatedValue()[0] + delta);
70      }
71  
72  }