WideLaneCombination.java
- /* Copyright 2002-2024 CS GROUP
- * Licensed to CS GROUP (CS) under one or more
- * contributor license agreements. See the NOTICE file distributed with
- * this work for additional information regarding copyright ownership.
- * CS licenses this file to You under the Apache License, Version 2.0
- * (the "License"); you may not use this file except in compliance with
- * the License. You may obtain a copy of the License at
- *
- * http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
- package org.orekit.estimation.measurements.gnss;
- import org.hipparchus.util.MathArrays;
- import org.orekit.gnss.Frequency;
- import org.orekit.gnss.MeasurementType;
- import org.orekit.gnss.SatelliteSystem;
- /**
- * Wide-Lane combination.
- * <p>
- * This combination are used to create a signal
- * with a significantly wide wavelength.
- * This longer wavelength is useful for cycle-slips
- * detection and ambiguity fixing
- * </p>
- * <pre>
- * f1 * m1 - f2 * m2
- * mWL = -----------------------
- * f1 - f2
- * </pre>
- * With:
- * <ul>
- * <li>mWL: Wide-laning measurement.</li>
- * <li>f1 : Frequency of the first measurement.</li>
- * <li>m1 : First measurement.</li>
- * <li>f2 : Frequency of the second measurement.</li>
- * <li>m1 : Second measurement.</li>
- * </ul>
- * <p>
- * Wide-Lane combination is a dual frequency combination.
- * The two measurements shall have different frequencies but they must have the same {@link MeasurementType}.
- * </p>
- * @author Bryan Cazabonne
- * @since 10.1
- */
- public class WideLaneCombination extends AbstractDualFrequencyCombination {
- /**
- * Package private constructor for the factory.
- * @param system satellite system for which the combination is applied
- */
- WideLaneCombination(final SatelliteSystem system) {
- super(CombinationType.WIDE_LANE, system);
- }
- /** {@inheritDoc} */
- @Override
- protected double getCombinedValue(final double obs1, final Frequency f1,
- final double obs2, final Frequency f2) {
- // Get the ration f/f0
- final double ratioF1 = f1.getRatio();
- final double ratioF2 = f2.getRatio();
- // Perform combination
- return MathArrays.linearCombination(ratioF1, obs1, -ratioF2, obs2) / (ratioF1 - ratioF2);
- }
- /** {@inheritDoc} */
- @Override
- protected double getCombinedFrequency(final Frequency f1, final Frequency f2) {
- return f1.getMHzFrequency() - f2.getMHzFrequency();
- }
- }