public static void Example1() //================[ Basic DFT Example ]================
{
// Generate a test signal,
// 1 Vrms at 20,000 Hz
// Sampling Rate = 100,000 Hz
// DFT Length is 1000 Points
double amplitude = 1.0;
double frequency = 20000;
UInt32 length = 1000;
double samplingRate = 100000;
double[] inputSignal = DSP.Generate.ToneSampling(amplitude, frequency, samplingRate, length);
// Instantiate a new DFT
DFT dft = new DFT();
// Initialize the DFT
// You only need to do this once or if you change any of the DFT parameters.
dft.Inicializar(length);
// Call the DFT and get the scaled spectrum back
Complex[] cSpectrum = dft.Executar(inputSignal);
// Convert the complex spectrum to magnitude
double[] lmSpectrum = DSP.ConvertComplex.ToMagnitude(cSpectrum);
// Note: At this point lmSpectrum is a 501 byte array that
// contains a properly scaled Spectrum from 0 - 50,000 Hz
// For plotting on an XY Scatter plot generate the X Axis frequency Span
double[] freqSpan = dft.FrequencySpan(samplingRate);
// At this point a XY Scatter plot can be generated from,
// X axis => freqSpan
// Y axis => lmSpectrum
// In this example the maximum value of 1 Vrms is located at bin 200 (20,000 Hz)
}
// For example 11
private static void DftWorker_DoWork(object sender, DoWorkEventArgs e)
{
// DFT Length is 30000 Points, so it takes a very long time!
double amplitude = 1.0;
double frequency = 20000;
UInt32 length = 30000;
double samplingRate = 100000;
double[] inputSignal = DSP.Generate.ToneSampling(amplitude, frequency, samplingRate, length);
// Instantiate a new DFT
DFT dft = new DFT();
// Initialize the DFT
// You only need to do this once or if you change any of the DFT parameters.
dft.Inicializar(length);
// Call the DFT and get the scaled spectrum back
Complex[] cSpectrum = dft.Executar(inputSignal);
// Convert the complex spectrum to magnitude
double[] lmSpectrum = DSP.ConvertComplex.ToMagnitude(cSpectrum);
}