Numerical - Calculate Sampling rate

Calculate the minimum sampling rate to avoid aliasing when a continuous time signal is given by x(t) = 5 cos 400πt

Options:

a) 100 Hz
b) 200 Hz
c) 400 Hz
d) 250 Hz

Correct Answer: c) 400 Hz

Explanation:

In the given signal, the highest frequency is given by f= 400 π/ 2π

= 200 Hz

The minimum sampling rate required to avoid aliasing is given by Nyquist rate. The nyquist rate is = 2*f

= 2* 200

= 400 Hz.