1. ## Shannon's sampling theorem

Is Shannon's sampling theorem, which says one must sample a signal with a sampling frequency larger than 2 times the maximum frequency component of the signal, really a theorem? Or, is it just a reasonable rule? If it is a real theorem, where can I find a rigorous version of it? Thanks a lot.

2. Originally Posted by abygailon
Is Shannon's sampling theorem, which says one must sample a signal with a sampling frequency larger than 2 times the maximum frequency component of the signal, really a theorem? Or, is it just a reasonable rule? If it is a real theorem, where can I find a rigorous version of it? Thanks a lot.
The sampling theorem is: A signal with no frequency componets above B Hz can be reconstructed exactly by sampling points spaced by 1/(2B) seconds.

See here

CB

3. Thanx a lot. Now it makes sense, it is a sufficient condition.

4. Originally Posted by abygailon
Thanx a lot. Now it makes sense, it is a sufficient condition.
Any higher sampling rate will do, yes.

CB