The error in the following code:
F0 =13;
T0 =1/F0;
Ts = 0.07;
t = 0:Ts:13*T0;
x = real(exp(j*(2*pi*F0*t-pi/2)));
plot(t,x)
is the value for Ts is too large. The sampling frequency needs to much smaller to get a good result.
If we change the value to 1/2000 the code will work as expected.
