int SyncDetected(float[] incomingSamples, int startingIndex, int numSamples)
{
if (numSamples == 0)
{
// Adjust demodulator
Demodulator.RotateCorrection = SyncCorr.RotateCorrection;
// Frequency Correction on receiving the first Sync block
// Only apply correction if the accumulated error will be more that 45 degrees
if (Math.Abs(SyncCorr.FrequencyCorrection.Degrees * SyncCorr.CorrelationMaxLength) > 45)
{
Demodulator.FrequencyCorrection = SyncCorr.FrequencyCorrection;
}
// Get the last 15*32 symbols
SyncCorr.GetLastData(SyncCorr.CorrelationMaxIndex, PreambleBlock, 15 * 32);
int D1, D2, Z, Cnt;
ProcessPreamble(out D1, out D2, out Cnt, out Z);
// Check for the reasonable values that we extracted from the preamble
// Get the mode from D1 and D2, verify counter
ModeInfo mi = MILSTD188_110B.modemModes[D1, D2];
if (Z == 0 && mi != null && Cnt < mi.PreambleSize)
{
this.CurrentMode = mi;
PreambuleCounter = Cnt;
if (PreambuleCounter == 0)
{
InitReceiveData();
NextFunction = ReceiveData;
numSamples = 0;
}
else
{
PreambleIdx = 0;
SyncCorr.StartCorrectionProcess();
}
}
else
{
NextFunction = LookForSymbolSync;
numSamples = 0;
}
}
int i, nProc;
for (i = 0; i < numSamples; i += nProc)
{
// Decode the preamble chunks
nProc = Math.Min(numSamples - i, DECFACTOR);
int nSym = Demodulator.Process(incomingSamples, startingIndex + i, nProc);
while (nSym-- > 0)
{
IQ IQData = Demodulator.GetData();
PreambleBlock[PreambleIdx++] = IQData;
SyncCorr.Process(IQData);
if (PreambleIdx >= PreambleBlock.Length)
{
// Do demodulator correction
Demodulator.RotateCorrection *= SyncCorr.RotateCorrection;
Demodulator.FrequencyCorrection *= (IQ.UNITY + 0.05f * SyncCorr.FrequencyCorrection) / 1.05f;
int D1, D2, Z, Cnt;
ProcessPreamble(out D1, out D2, out Cnt, out Z);
// Check the values that we extracted from the preambule
// Get the mode from D1 and D2, verify counter
if (Z == 0 && D1 == CurrentMode.D1 && D2 == CurrentMode.D2 && Cnt == (PreambuleCounter - 1))
{
PreambuleCounter = Cnt;
if (PreambuleCounter == 0)
{
InitReceiveData();
NextFunction = ReceiveData;
numSamples = 0;
break;
}
else
{
PreambleIdx = 0;
SyncCorr.StartCorrectionProcess();
}
}
else
{
NextFunction = LookForSymbolSync;
numSamples = 0;
break;
}
}
}
}
return(i);
}
public void Add(ModeInfo data)
{
ModeArray.Add(data);
}
