public static Signal DeModulate(Signal PassBand, float carrier_frequency, float threshold = 0)
{
Signal ccarrier = new Sinusoidal(carrier_frequency, 0, -1, 1, PassBand.Samples.Length); // generate coherent carrier
Signal demod = ccarrier * PassBand; // multiply the carrier and the passband signal
var s = demod.Samples.Split((int)PassBand.SamplingRate);
bool[] bits = new bool[s.Count()];
int j = 0;
foreach (var item in s)
{
var sm = item.Sum();
bits[j] = sm > threshold;
j++;
}
return new BinaryData(bits, demod.Samples.Length);
}
public static Signal BFSK_DeModulate(Signal passband, float f1, float f2, float threshold = 10)
{
Sinusoidal c = new Sinusoidal(f1, 0, passband.SamplingRate, 1, passband.Samples.Length);
Signal demod = passband * c;
var s = demod.Samples.Split((int)passband.SamplingRate);
bool[] bits = new bool[s.Count()];
int j = 0;
foreach (var item in s)
{
var sm = item.Sum();
bits[j] = sm > threshold;
j++;
}
return new BinaryData(bits, demod.Samples.Length);
}
public static Signal Modulate(Signal Baseband, float CarrierFrequency, float CarrierAmplitude = 1)
{
Signal Carrier = new Sinusoidal(CarrierFrequency, 0, Baseband.SamplingRate, 1, Baseband.Samples.Length);
return Baseband * Carrier;
}