ACF/CCF

clear
close all
%Initial Data
A = 8e-3;
F0 = 3000;
Fs = 48000;
Q = 3;
N = 10;
m = 0;
sq = A;
D = 1/Q*100;
t = 0:1/Fs:N*1/F0-1/Fs;
t0 = -(1/F0-1/Fs):1/Fs:1/F0-1/Fs;
%Single Rectangular Signal
y0 = A*rectpuls(t0, 1/F0*(D/100));
subplot(3, 3, 1)
plot(t0, y0)
title('Original Single Signal')
%Periodic Rectangular Signal
y1 = A*(square(2*pi*F0*t, D));
subplot(3, 3, 2);
plot(t, y1);
title('Origianl Periodic Signal');
%White Noise
y2 = sq*(rand(1, length(y1))-0.5);
subplot(3, 3, 3)
plot(t, y2)
title('White Noise')
%Signal-noise Mixture
y3 = y1 + y2;
subplot(3, 3, 4)
plot(t, y3)
title('Signal-noise mixture')
%ACF of Single Rectangular Signal
[ACF_y0, lags0] = xcorr(y0);
subplot(3, 3, 5)
plot(lags0, ACF_y0)
title('Single Signal ACF')
%ACF of Periodic Rectangular Signal
[ACF_y1, lags1] = xcorr(y1);
subplot(3, 3, 6)
plot(lags1, ACF_y1)
title('Pediodic Signal ACF')
%Interval from Mixture
start_T = randi(N/2, 1, 1);
end_T = start_T+randi(N/2, 1, 1);
period =  floor(length(y3)/N);
y3_interval = y3(period*start_T:period*end_T);
subplot(3, 3, 7);
plot(t(period*start_T:period*end_T),y3_interval);
title('Interval from mixture');
[CCF_y3Xy3_interval, lags2] = xcorr(y3, y3_interval);
subplot(3, 3, 8)
plot(lags2,CCF_y3Xy3_interval)
title('Cross Correlation for Y3 and interval')
CCF_max = max(CCF_y3Xy3_interval);
disp(CCF_max)
CCF_max_index = find(CCF_y3Xy3_interval==CCF_max);
disp(CCF_max_index)
%Find original interval
left_border_index = round(CCF_max_index - length(y3_interval)/2);%?
right_border_index = round(CCF_max_index + length(y3_interval)/2);%?
display(left_border_index)
display(right_border_index)