public void decode(RadioLog.Common.SafeBitArray message, int start, int end)
{
/* load each of the nodes with deinterleaved constellations */
for (int index = 0; index < 49; index++)
{
Constellation c = getConstellation(message, index * 4);
mConstellationNodes[index].setConstellation(c);
}
/* test to see if constellations are correct - otherwise correct them */
ConstellationNode firstNode = mConstellationNodes[0];
if (!firstNode.startsWith(Dibit.D0) || !firstNode.isCorrect())
{
firstNode.correctTo(Dibit.D0);
}
/* clear constellations from original message */
message.ClearRange(start, end - start);
/* replace with decoded values from the nodes */
for (int index = 0; index < 49; index++)
{
ConstellationNode node = mConstellationNodes[index];
if (node.firstBit())
{
message.SetBit(start + (index * 2));
}
if (node.secondBit())
{
message.SetBit(start + (index * 2) + 1);
}
}
}
public static RadioLog.Common.SafeBitArray interleave(RadioLog.Common.SafeBitArray message, int start, int end)
{
RadioLog.Common.SafeBitArray original = message.CloneFromIndexToIndex(start, end);
/* Clear block bits in source message */
message.ClearRange(start, end);
/* Iterate only the set bits in the original message and apply
* the deinterleave -- we don't have to evaluate the 0 bits */
for (int i = original.nextSetBit(0);
i >= 0 && i < INTERLEAVE.Length;
i = original.nextSetBit(i + 1))
{
message.SetBit(start + INTERLEAVE[i]);
}
return message;
}