A Sample of Truth A sampler with a sampling rate of f, Hz may be described as a
ID: 2293837 • Letter: A
Question
A Sample of Truth A sampler with a sampling rate of f, Hz may be described as a continuous time system with by the function: Sampleryo y(t)- x(t)S(t - kT) Please indicate if the following statements are either: * Surely TRUE * Surely FALSE E (i.e. cannot be determined) INDETERMINAT A. Sampling is Causal B. Sampling is Invertible C. A Low-pass filter with a cut-off at fs is required for Antialiasing D. Let x(t) be a band-limited signal with X(ja) = 0 for lol > ?N. Then x(t) is uniquely determined by its samples y(t) ing > 4???. E. Let x(t) be a band-limited signal with X(ja) 0 for lal >. Then the samples y(t) are uniquely determined if 4??N.Explanation / Answer
A.) TRUE
Reason: It is causal because (whether it is up sampling or down sampling) the output at time n depends only on samples you've seen up time n.
B.) FALSE Up sampling is invertible and down sampling is not invertible
Reason: Up sampling converts the sequence of lower sampling rate to a higher sampling rate wheras in downsampling higher to lower sampling rate is done.
C.) FALSE
REASON: It is fs/2 It blocks all frequencies that would create images in the sampled signal, before sampling the signal.
D.) TRUE
E.) FALSE