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  
22  /** Modifier for wind-up effect in GNSS {@link InterSatellitesPhase inter-satellites phase measurements}.
23   * @see InterSatellitesWindUpFactory
24   * @author Luc Maisonobe
25   * @since 12.0
26   */
27  public class InterSatellitesWindUp extends AbstractWindUp<InterSatellitesPhase> {
28  
29      /** Simple constructor.
30       * <p>
31       * The constructor is package protected to enforce use of {@link WindUpFactory}
32       * and preserve phase continuity for successive measurements involving the same
33       * satellite/receiver pair.
34       * </p>
35       * @param emitter emitter dipole
36       * @param receiver receiver dipole
37       */
38      InterSatellitesWindUp(final Dipole emitter, final Dipole receiver) {
39          super(emitter, receiver);
40      }
41  
42      /** {@inheritDoc} */
43      @Override
44      protected Rotation emitterToInert(final EstimatedMeasurementBase<InterSatellitesPhase> estimated) {
45          // we don't use the basic yaw steering attitude model from ESA navipedia page
46          // but rely on the attitude that was computed by the propagator, which takes
47          // into account the proper noon and midnight turns for each satellite model
48          return estimated.getStates()[1].toStaticTransform().getRotation().revert();
49      }
50  
51      /** {@inheritDoc} */
52      @Override
53      protected Rotation receiverToInert(final EstimatedMeasurementBase<InterSatellitesPhase> estimated) {
54          // we don't use the basic yaw steering attitude model from ESA navipedia page
55          // but rely on the attitude that was computed by the propagator, which takes
56          // into account the proper noon and midnight turns for each satellite model
57          return estimated.getStates()[0].toStaticTransform().getRotation().revert();
58      }
59  
60  }