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.models.earth.troposphere;
18  
19  import java.util.Collections;
20  import java.util.List;
21  
22  import org.hipparchus.CalculusFieldElement;
23  import org.orekit.bodies.FieldGeodeticPoint;
24  import org.orekit.bodies.GeodeticPoint;
25  import org.orekit.time.AbsoluteDate;
26  import org.orekit.time.FieldAbsoluteDate;
27  import org.orekit.utils.FieldTrackingCoordinates;
28  import org.orekit.utils.ParameterDriver;
29  import org.orekit.utils.TrackingCoordinates;
30  
31  /** Defines a constant tropospheric model.
32   * @author Luc Maisonobe
33   * @since 12.1
34   */
35  public class ConstantTroposphericModel implements TroposphericModel {
36  
37      /** Constant delay. */
38      private final TroposphericDelay delay;
39  
40      /** Simple constructor.
41       * @param delay constant delay
42       */
43      public ConstantTroposphericModel(final TroposphericDelay delay) {
44          this.delay = delay;
45      }
46  
47      /** {@inheritDoc} */
48      @Override
49      public TroposphericDelay pathDelay(final TrackingCoordinates trackingCoordinates,
50                                         final GeodeticPoint point,
51                                         final double[] parameters,
52                                         final AbsoluteDate date) {
53          return delay;
54      }
55  
56      /** {@inheritDoc} */
57      @Override
58      public <T extends CalculusFieldElement<T>> FieldTroposphericDelay<T> pathDelay(final FieldTrackingCoordinates<T> trackingCoordinates,
59                                                                                     final FieldGeodeticPoint<T> point,
60                                                                                     final T[] parameters,
61                                                                                     final FieldAbsoluteDate<T> date) {
62          final T zero = date.getField().getZero();
63          return new FieldTroposphericDelay<>(zero.newInstance(delay.getZh()),
64                                              zero.newInstance(delay.getZw()),
65                                              zero.newInstance(delay.getSh()),
66                                              zero.newInstance(delay.getSw()));
67      }
68  
69      /** {@inheritDoc} */
70      @Override
71      public List<ParameterDriver> getParametersDrivers() {
72          return Collections.emptyList();
73      }
74  
75  }