Nyquist-Shannon Sampling Theorem

In signal processing, the Nyquist–Shannon sampling theorem states that a continuous-time signal bandlimited to maximum frequency f_max (no spectral energy above f_max) can be exactly reconstructed from its uniform samples taken at sampling frequency f_s provided f_s > 2 f_max (often stated as f_s ≥ 2 f_max with additional technical conditions).