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.generation;
18  
19  import org.hipparchus.random.CorrelatedRandomVectorGenerator;
20  import org.orekit.estimation.measurements.AngularRaDec;
21  import org.orekit.estimation.measurements.GroundStation;
22  import org.orekit.estimation.measurements.ObservableSatellite;
23  import org.orekit.frames.Frame;
24  import org.orekit.propagation.sampling.OrekitStepInterpolator;
25  import org.orekit.time.AbsoluteDate;
26  
27  import java.util.Map;
28  
29  /** Builder for {@link AngularRaDec} measurements.
30   * @author Luc Maisonobe
31   * @since 9.3
32   */
33  public class AngularRaDecBuilder extends AbstractMeasurementBuilder<AngularRaDec> {
34  
35      /** Zero value for initial dummy measurement. */
36      private static final double[] ZERO = { 0.0, 0.0 };
37  
38      /** Ground station from which measurement is performed. */
39      private final GroundStation station;
40  
41      /** Reference frame in which the right ascension - declination angles are given. */
42      private final Frame referenceFrame;
43  
44      /** Simple constructor.
45       * @param noiseSource noise source, may be null for generating perfect measurements
46       * @param station ground station from which measurement is performed
47       * @param referenceFrame Reference frame in which the right ascension - declination angles are given
48       * @param sigma theoretical standard deviation
49       * @param baseWeight base weight
50       * @param satellite satellite related to this builder
51       */
52      public AngularRaDecBuilder(final CorrelatedRandomVectorGenerator noiseSource,
53                                 final GroundStation station, final Frame referenceFrame,
54                                 final double[] sigma, final double[] baseWeight,
55                                 final ObservableSatellite satellite) {
56          super(noiseSource, sigma, baseWeight, satellite);
57          this.station        = station;
58          this.referenceFrame = referenceFrame;
59      }
60  
61      /** {@inheritDoc} */
62      @Override
63      protected AngularRaDec buildObserved(final AbsoluteDate date,
64                                           final Map<ObservableSatellite, OrekitStepInterpolator> interpolators) {
65          return new AngularRaDec(station, referenceFrame, date, ZERO,
66                                  getTheoreticalStandardDeviation(),
67                                  getBaseWeight(), getSatellites()[0]);
68      }
69  
70  }