1   /* Copyright 2022-2025 Thales Alenia Space
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.gnss;
18  
19  import org.hipparchus.geometry.euclidean.threed.Rotation;
20  import org.orekit.estimation.measurements.EstimatedMeasurementBase;
21  import org.orekit.estimation.measurements.GroundStation;
22  import org.orekit.frames.Frame;
23  import org.orekit.utils.TimeStampedPVCoordinates;
24  
25  /** Modifier for wind-up effect in GNSS {@link Phase phase measurements}.
26   * @see WindUpFactory
27   * @author Luc Maisonobe
28   * @since 10.1
29   */
30  public class WindUp extends AbstractWindUp<Phase> {
31  
32      /** Simple constructor.
33       * <p>
34       * The constructor is package protected to enforce use of {@link WindUpFactory}
35       * and preserve phase continuity for successive measurements involving the same
36       * satellite/receiver pair.
37       * </p>
38       * @param emitter emitter dipole
39       */
40      WindUp(final Dipole emitter) {
41          super(emitter, Dipole.CANONICAL_I_J);
42      }
43  
44      /** {@inheritDoc} */
45      @Override
46      protected Rotation emitterToInert(final EstimatedMeasurementBase<Phase> estimated) {
47          // we don't use the basic yaw steering attitude model from ESA navipedia page
48          // but rely on the attitude that was computed by the propagator, which takes
49          // into account the proper noon and midnight turns for each satellite model
50          return estimated.getStates()[0].toStaticTransform().getRotation().revert();
51      }
52  
53      /** {@inheritDoc} */
54      @Override
55      protected Rotation receiverToInert(final EstimatedMeasurementBase<Phase> estimated) {
56          final TimeStampedPVCoordinates[] participants = estimated.getParticipants();
57          final Frame                      inertial     = estimated.getStates()[0].getFrame();
58          final GroundStation              station      = estimated.getObservedMeasurement().getStation();
59          return station.getOffsetToInertial(inertial, participants[1].getDate(), false).getRotation();
60      }
61  
62  }