Question 1
Signals & SystemsDTFT
The DTFT of delta[n] is?
Correct Answer: B. 1
Explanation: By definition, the only nonzero sequence sample is at n=0, so X(e^(jω))=1.
Reference: Standard signals and systems: dtft
DTFT MCQs
Practice DTFT MCQs with four options, answers and explanations for focused Electronics & Telecommunication Engineering revision.
Question 2
Signals & SystemsDTFT
If x[n] is delayed by n0 samples, its DTFT is multiplied by?
Correct Answer: A. e^(-jωn0)
Explanation: The DTFT time-shift property is x[n-n0] ↔ e^(-jωn0)X(e^(jω)).
Reference: Standard signals and systems: dtft
Question 3
Signals & SystemsDTFT
The discrete-time Fourier transform X(e^(jω)) is periodic in ω with period?
Correct Answer: B. 2π
Explanation: The DTFT is periodic in angular frequency with period 2π because e^(-j(ω+2π)n)=e^(-jωn) for integer n.
Reference: Standard signals and systems: dtft
Question 4
Signals & SystemsDTFT
For a real-valued sequence x[n], its DTFT has conjugate symmetry given by?
Correct Answer: A. X(e^(-jω))=X*(e^(jω))
Explanation: A real time-domain sequence has a conjugate-symmetric DTFT: X(e^(-jω))=X*(e^(jω)).
Reference: Standard signals and systems: dtft