001 package edu.nrao.sss.model.resource.vla;
002
003 import java.math.BigDecimal;
004 import java.util.ArrayList;
005 import java.util.List;
006 import java.util.SortedSet;
007 import java.util.TreeSet;
008
009 import javax.xml.bind.annotation.XmlElement;
010 import javax.xml.bind.annotation.XmlRootElement;
011
012 import edu.nrao.sss.astronomy.PolarizationType;
013 import edu.nrao.sss.electronics.DigitalSignal;
014 import edu.nrao.sss.measure.Frequency;
015 import edu.nrao.sss.measure.FrequencyRange;
016 import edu.nrao.sss.measure.FrequencyUnits;
017 import edu.nrao.sss.model.resource.CorrelatorBasebandAbs;
018 import edu.nrao.sss.model.resource.CorrelatorConfiguration;
019 import edu.nrao.sss.model.resource.CorrelatorSubband;
020
021 /**
022 * A baseband pair of the VLA correlator.
023 * <p>
024 * This class is here for completeness but might never be used.
025 * We have a short-term mission to support the VLA correlator,
026 * but VLA support will end once WIDAR takes over.</p>
027 * <p>
028 * <b>Version Info:</b>
029 * <table style="margin-left:2em">
030 * <tr><td>$Revision: 2271 $</td></tr>
031 * <tr><td>$Date: 2009-04-28 12:02:17 -0600 (Tue, 28 Apr 2009) $</td></tr>
032 * <tr><td>$Author: dharland $ (last person to modify)</td></tr>
033 * </table></p>
034 *
035 * @author David M. Harland
036 * @since 2008-06-25
037 */
038 @XmlRootElement
039 public class VlaBasebandPair
040 extends CorrelatorBasebandAbs
041 {
042 private static final Frequency MIN_BW =
043 new Frequency("195312.5", FrequencyUnits.HERTZ);
044
045 private static final Frequency MAX_BW =
046 new Frequency("50000000.0", FrequencyUnits.HERTZ);
047
048 @XmlElement private DigitalSignal inputSignalA;
049 @XmlElement private DigitalSignal inputSignalB;
050
051 private VlaConfiguration container;
052
053 /**
054 * Helps create a new VLA baseband pair.
055 * @throws IllegalArgumentException
056 * if {@code input} is <i>null</i>.
057 */
058 protected VlaBasebandPair(DigitalSignal inputA, DigitalSignal inputB)
059 {
060 this();
061 initInput(inputA, inputB);
062 }
063
064 //This is here only for persistence mechanisms
065 protected VlaBasebandPair()
066 {
067 super();
068 container = null;
069 }
070
071 /** Sets the input signal for this baseband. */
072 private void initInput(DigitalSignal inputA, DigitalSignal inputB)
073 {
074 if (inputA == null || inputB == null)
075 throw new IllegalArgumentException(
076 "Cannot configure correlator baseband with a NULL input signal.");
077
078 //TODO Do we need to compare the inputs to make sure they have
079 // same freq range? Same init quant? Diff polzns?
080 inputSignalA = inputA;
081 inputSignalB = inputB;
082 }
083
084 //============================================================================
085 // IDENTIFICATION
086 //============================================================================
087
088 /* (non-Javadoc)
089 * @see edu.nrao.sss.model.resource.CorrelatorBaseband#getName()
090 */
091 public String getName()
092 {
093 return inputSignalA.getName() + "/" + inputSignalB.getName();
094 }
095
096 /* (non-Javadoc)
097 * @see edu.nrao.sss.model.resource.CorrelatorBaseband#isSinglet()
098 */
099 public boolean isSinglet() { return false; }
100
101 //============================================================================
102 // CONTAINER
103 //============================================================================
104
105 /**
106 * Returns the correlator configuration that holds this baseband.
107 * It is possible for the returned value to be <i>null</i>.
108 * If not <i>null</i>, the returned object will always be of type
109 * {@link VlaConfiguration}.
110 */
111 protected CorrelatorConfiguration getContainer()
112 {
113 return container;
114 }
115
116 /**
117 * Sets the correlator configuration to which this baseband belongs.
118 * The {@code newContainer} is allowed to be <i>null</i>.
119 * If not <i>null</i>, the type of {@code newContainer} must be
120 * {@link VlaConfiguration}.
121 */
122 protected void setContainer(CorrelatorConfiguration newContainer)
123 {
124 container = (VlaConfiguration)newContainer;
125 }
126
127 //============================================================================
128 // FREQUENCY
129 //============================================================================
130
131 /* (non-Javadoc)
132 * @see edu.nrao.sss.model.resource.CorrelatorBaseband#getProxiedRange()
133 */
134 public FrequencyRange getProxiedRange()
135 {
136 return getProxiedRange(inputSignalA);
137 }
138
139 /* (non-Javadoc)
140 * @see edu.nrao.sss.model.resource.CorrelatorBaseband#proxiedRangeIsReversed()
141 */
142 public boolean proxiedRangeIsReversed()
143 {
144 return inputSignalA.proxiedRangeIsReversed();
145 }
146
147 /* (non-Javadoc)
148 * @see edu.nrao.sss.model.resource.CorrelatorBaseband#getMinimumBandwidth()
149 */
150 public Frequency getMinimumBandwidth()
151 {
152 return MIN_BW.clone();
153 }
154
155 /* (non-Javadoc)
156 * @see edu.nrao.sss.model.resource.CorrelatorBaseband#getMaximumBandwidth()
157 */
158 public Frequency getMaximumBandwidth()
159 {
160 return MAX_BW.clone();
161 }
162
163 /* (non-Javadoc)
164 * @see edu.nrao.sss.model.resource.CorrelatorBaseband#hasDiscreteBandwidths()
165 */
166 public boolean hasDiscreteBandwidths()
167 {
168 return true;
169 }
170
171 /* (non-Javadoc)
172 * @see edu.nrao.sss.model.resource.CorrelatorBaseband#getAllowableBandwidths()
173 */
174 public SortedSet<Frequency> getAllowableBandwidths()
175 {
176 SortedSet<Frequency> bws = new TreeSet<Frequency>();
177
178 BigDecimal minHz = getMinimumBandwidth().toUnits(FrequencyUnits.HERTZ);
179
180 double maxHz =
181 getMaximumBandwidth().toUnits(FrequencyUnits.HERTZ).doubleValue();
182
183 //Only non-negative powers-of-two multiples of min are allowed
184 //However, the frequency that corresponds to twice
185 //the minimum is not allowed.
186 bws.add(new Frequency(minHz, FrequencyUnits.HERTZ).normalize());
187 for (double hertz = minHz.doubleValue() * 4.0; hertz <= maxHz; hertz *= 2.0)
188 {
189 bws.add(new Frequency(new BigDecimal(hertz),
190 FrequencyUnits.HERTZ).normalize());
191 }
192 return bws;
193 }
194
195 //============================================================================
196 // QUANTIZATION & POLARIZATION
197 //============================================================================
198
199 /* (non-Javadoc)
200 * @see edu.nrao.sss.model.resource.CorrelatorBaseband#getInitialQuantization()
201 */
202 public int getInitialQuantization()
203 {
204 return inputSignalA.getBitDepth();
205 }
206
207 /** @deprecated Use {@link #getPolarizations()}. */
208 @Deprecated
209 public PolarizationType getPolarization()
210 {
211 return getPolarizations().get(0);
212 }
213
214 /* (non-Javadoc)
215 * @see edu.nrao.sss.model.resource.CorrelatorBaseband#getPolarizations()
216 */
217 public List<PolarizationType> getPolarizations()
218 {
219 List<PolarizationType> answer = new ArrayList<PolarizationType>();
220 answer.add(inputSignalA.getPolarization());
221 answer.add(inputSignalB.getPolarization());
222 return answer;
223 }
224
225 //============================================================================
226 // SUBBAND
227 //============================================================================
228
229 /* (non-Javadoc)
230 * @see edu.nrao.sss.model.resource.CorrelatorBaseband#getMaxSubbandCount()
231 */
232 public int getMaxSubbandCount()
233 {
234 return 1;
235 }
236
237 /* (non-Javadoc)
238 * @see edu.nrao.sss.model.resource.CorrelatorBaseband#makeNewSubband()
239 */
240 public VlaSubband makeNewSubband()
241 {
242 return new VlaSubband();
243 }
244
245 /* (non-Javadoc)
246 * @see edu.nrao.sss.model.resource.CorrelatorBaseband#getSubbandGrid()
247 */
248 public SortedSet<Frequency> getSubbandGrid()
249 {
250 return new TreeSet<Frequency>();
251 }
252
253 public void addSubband(CorrelatorSubband newSubband)
254 {
255 addNewSubband((VlaSubband)newSubband);
256 }
257
258 //============================================================================
259 //
260 //============================================================================
261
262 /**
263 * Returns a copy of this baseband.
264 * <p>
265 * If anything goes wrong during the cloning procedure,
266 * a {@code RuntimeException} will be thrown.</p>
267 */
268 @Override
269 public VlaBasebandPair clone()
270 {
271 VlaBasebandPair clone = null;
272
273 try
274 {
275 clone = (VlaBasebandPair)super.clone();
276
277 clone.inputSignalA = this.inputSignalA.clone();
278 clone.inputSignalB = this.inputSignalB.clone();
279 }
280 catch (Exception ex)
281 {
282 throw new RuntimeException(ex);
283 }
284
285 return clone;
286 }
287
288 /** Returns <i>true</i> if {@code o} is equal to this baseband. */
289 @Override
290 public boolean equals(Object o)
291 {
292 //Quick exit if super class says not equal
293 if (!super.equals(o))
294 return false;
295
296 //A safe cast if we got this far
297 VlaBasebandPair other = (VlaBasebandPair)o;
298
299 //Equal if they have the same input signals, even if those
300 //signals are in a different order
301 return
302 (other.inputSignalA.equals(this.inputSignalA) &&
303 other.inputSignalB.equals(this.inputSignalB))
304 ||
305 (other.inputSignalA.equals(this.inputSignalB) &&
306 other.inputSignalB.equals(this.inputSignalA));
307 }
308
309 /** Returns a hash code value for this baseband. */
310 @Override
311 public int hashCode()
312 {
313 //Taken from the Effective Java book by Joshua Bloch.
314 //The constants 17 & 37 are arbitrary & carry no meaning.
315 int result = super.hashCode();
316
317 //You MUST keep this method in sync w/ the equals method
318
319 //Want two BBs that have the same input signals to give same
320 //hashCode, even if those signals are ordered differently.
321 result = 37 * result + inputSignalA.hashCode() + inputSignalB.hashCode();
322
323 return result;
324 }
325 }