problem to transform a signal with fft

i have the signal

h(t)=sinc((10^3)*t)

and i want to transform it to fourier with fft. Can you tell me the right way because it confuses me?

Answer 1

[Walter Roberson]

http://www.mathworks.com/help/signal/ref/sinc.html

start_time = 0;
end_time = 20;   %for example
t = linspace(start_time, end_time, 501);   %create time vector
h = sinc(10^3*t);
hf = fft(h);

Now hf is the transformed value. It will have complex coefficients.

[chris m]

so if i have time from -0.01 to 0.01 with step 0.0001 and h(t) then to compute fourier of h is:

t = -0.01:0.0001:0.01;
h = sinc((10^3)*t);
H = fft(h);
plot(H)

is this right? should not you get samples >2*fmax

[Walter Roberson]

H is going to be complex; if you plot it that way you will get a complex plot. You should probably plot(abs(H))