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.BistaticRangeRate;
21  import org.orekit.estimation.measurements.GroundStation;
22  import org.orekit.estimation.measurements.ObservableSatellite;
23  import org.orekit.propagation.sampling.OrekitStepInterpolator;
24  import org.orekit.time.AbsoluteDate;
25  
26  import java.util.Map;
27  
28  /** Builder for {@link BistaticRangeRate} measurements.
29   * @author Pascal Parraud
30   * @since 11.2
31   */
32  public class BistaticRangeRateBuilder extends AbstractMeasurementBuilder<BistaticRangeRate> {
33  
34      /** Emitter ground station. */
35      private final GroundStation emitter;
36  
37      /** Receiver ground station. */
38      private final GroundStation receiver;
39  
40      /** Simple constructor.
41       * @param noiseSource noise source, may be null for generating perfect measurements
42       * @param emitter emitter ground station
43       * @param receiver receiver ground station, from which measurement is performed
44       * @param sigma theoretical standard deviation
45       * @param baseWeight base weight
46       * @param satellite satellite related to this builder
47       */
48      public BistaticRangeRateBuilder(final CorrelatedRandomVectorGenerator noiseSource,
49                                      final GroundStation emitter, final GroundStation receiver,
50                                      final double sigma, final double baseWeight,
51                                      final ObservableSatellite satellite) {
52          super(noiseSource, sigma, baseWeight, satellite);
53          this.emitter  = emitter;
54          this.receiver = receiver;
55      }
56  
57      /** {@inheritDoc} */
58      @Override
59      protected BistaticRangeRate buildObserved(final AbsoluteDate date,
60                                                final Map<ObservableSatellite, OrekitStepInterpolator> interpolators) {
61          return new BistaticRangeRate(emitter, receiver, date, 0.0,
62                                       getTheoreticalStandardDeviation()[0],
63                                       getBaseWeight()[0], getSatellites()[0]);
64      }
65  
66  }