what does if(s(j+1)==y1(j+1)) mean?

%Demodulation process
for i=1:6
    for j=(i-1)*100:i*100
        if(s(j+1)==y1(j+1))
            x(j+1)=1;
        else
            x(j+1)=0;
        end
    end
end
%plot ASK Demodulated Signal
subplot(4,1,4);
plot(
t,x,'r');
title('ASK Demodulated Signal');
xlabel('time(s)');
ylabel('amplitude');

[David Hill]

comparing array 's' at index j+1 to array 'y1' at index j+1, if they are equal (==) then set array x at j+1 to 1.

[ainun syafiqah]

can i also know what type of demodulation is this?

[dpb]

"can i also know what type of demodulation is this?"

Dunno...what's a Modulated ASK signal?

Looks like the whole double loop could be dispensed with as

i1=1;
i2=601;
x=double(s(i1:i2)==y1(i1:i2));

Answer 1

[SaiDileep Kola]

Ask modulation is simply multiplying data sequence(0,1) with a continuous wave, so you get signal at places of 1's and get no signal at 0's, the reverse is done at demodulation to check if the signal is present and assign as 1 and others as 0.