% Chirp signal

fs = 11025;
dur = 2;

a = 700;
b = 440;

% a=-400;
% b=2000;


tt = 0:1/fs:dur;

xx= cos( a*pi*tt.^2 + b*pi*tt);

sound(0.9*xx/max(abs(xx)),fs)

spectrogram(xx, 256, 128, 256, fs,'yaxis')
