examp32.m

ADSP TOOLBOX: Version 2.0 and gui m-files

clc,echo on 
%EXAMPLE 32 
ts=0.01;t=0:ts:2;N1=length(t);  % Set up time array 
x=sin(2*20*pi*t);               % Signal x 
z1=2*randist(x);x1=x+z1;        % Noisy signal z1 
z2=2*randist(x);x2=x+z2;        % Noisy signal z2 
cc=conv(x1,fliplr(x2));         % Correlation of x1 and x2  
N=length(cc);                   % Length of correlation 
tc=-(N1-1):N1-1;                % Correlation index 
figure(1)
subplot(311),plot(t,x1)
title('x1=sin(2*20*pi*t)+2*randist(x)')
subplot(312),plot(t,x1)
title('x2=sin(2*20*pi*t)+2*randist(x)')
subplot(313),plot(tc,cc);%pause(2)           % Plot correlation
title('cc=conv(x1,fliplr(x2))')
f=((0:N-1)-N/2)/N/ts;                 % FFT frequency axis f
f1=((0:N1-1)-N1/2)/N1/ts;
x1spec=abs(fftshift(fft(x1)))/N;
x2spec=abs(fftshift(fft(x2)))/N;
ccspec=abs(fftshift(fft(cc)))/N;% FFT (magnitude) of correlation
figure(2)
subplot(311),plot(f1,x1spec);
subplot(312),plot(f1,x2spec);
subplot(313),plot(f,ccspec);                 % Plot spectrum of correlation 
echo off %end of example