Shannon's sampling theorem
If a continuous, band-limited signal contains no frequency components higher than fc, then we can recover the original signal without distortion if we sample at a rate of at least 2fc samples/second
http://www.videomicroscopy.com/vancouverlecture/nyquist.htm
- 2fc is called the Nyquist rate
- Real life
- Sample at 2.5fc or faster
- Sample clock should not be coherent with the input signal