clc;
fs = 2000; %sampling frequency
dt = 1/fs; %seconds per sample
StopTime = 10; %seconds
t = (0:dt:StopTime);
F = 50.*t; %Sinewave frequency {Hertz)
amp = 1000;
The following is equivalent to LFM (linear frequency modulation) signal.
for i= 1:length(t);
data(i) = amp*sin(2*pi*F(i)*t(i));
end;
%audiowrite('varFsin.wav', data, fs);
sound(data);
figure(1)
clf(1);
plot(t, data)
title('Sine Wave');
figure(2)
spectrogram(data, [80], [40], [256], fs, 'yaxis')
y = fft(data);
n = length(data); %number of samples
f = (0:n-1)*(fs/n); %frequency range
power = abs(y).^2/n; %power of the DFT
figure(3);
powershift = fftshift(power);
fshift = (-n/2:n/2-1)*(fs/n); % zero-centered frequency range
plot(fshift,powershift)
xlabel('frequency')
ylabel('power')
This is not really harmonic. The spectrum has transition region around 0 and +/-fs/2. You have no harmonics to remove.
