clear all;
an=[1,0.3,-0.8,0.5,-0.4,0.2];tn=[0,1,2,3,4,5;0,0.1,0.2,0.3,0.4,0.5];
signal=[0, zeros(1,0),ones(1,501),zeros(1,1000)]; % transmitted signal
for k=1:2; %for two cases
for i=1:6;
ray(i,:)=an(i)*[0, zeros(1,(100*tn(k,i))),ones(1,501),zeros(1,(1000-100*tn(k,i)))];
end
y(k,:)=sum(ray(:,1:end));
end
t=((1:1:length(y(1,:)))-1)*10^(-2);
subplot(2,2,1);plot(t,signal);
ylabel('transmitted signal s(t)');
title('case 1 & case 2 & case 3')
axis([ 0 20 -0.5 1.5])
subplot(2,2,2);plot(t,y(1,:));
ylabel('received signal y(t)');
title('case 1: large delay spread')
subplot(2,2,4);
plot(t,y(2,:));
xlabel('Time(us)');
ylabel('received signal y(t)');
title('case 2: small delay spread')

noise = 0.5*rands(1,length(signal));
subplot(2,2,3);plot(t,signal);
ylabel('transmitted signal s(t)');
title('case 3: ')