n = [0:127];
x = (3*sin((n*pi)/8)+3).*(heaviside(n) - heaviside(n - 63));
z = (7*cos((n*pi)/16).*cos(n*pi)).*(heaviside(n) - heaviside(n - 63));
w = z + x;
h = 0.5*sinc(0.5*(n-31)).*(heaviside(n) - heaviside(n - 63));
y = conv(w, h, 'same');
xk = fft(x);
zk = fft(z);
q = (0:length(zk)-1)*128/length(zk);
f = (0:length(xk)-1)*128/length(xk);
figure 2
plot(q, zk);