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Sampling MCQs

Practice Sampling MCQs with four options, answers and explanations for focused Electronics & Telecommunication Engineering revision.

Question 1
Signals & SystemsSampling

According to the sampling theorem, a band-limited signal should be sampled at a rate of at least?

  • AHalf the highest signal frequency
  • BEqual to the highest signal frequency
  • CTwice the highest signal frequency
  • DFour times the lowest signal frequency
Report an error
Correct Answer: C. Twice the highest signal frequency
Explanation: For ideal reconstruction, the sampling frequency must be at least twice the highest frequency component of the band-limited signal.
Reference: Nyquist sampling theorem
Question 4
Communication SystemsSampling

If a 4 kHz sinusoid is sampled at 6 kHz, the sampling theorem is?

  • ASatisfied exactly
  • BSatisfied with large margin
  • CNot satisfied
  • DIndependent of sampling rate
Report an error
Correct Answer: C. Not satisfied
Explanation: For fm=4 kHz, the minimum Nyquist rate is 8 kHz. Sampling at 6 kHz can cause aliasing.
Reference: Standard communication systems: sampling
Question 5
Communication SystemsSampling

Aliasing occurs when?

  • ADifferent frequency components become indistinguishable after inadequate sampling
  • BThe carrier amplitude becomes zero
  • CA signal is amplified linearly
  • DQuantization levels become infinite
Report an error
Correct Answer: A. Different frequency components become indistinguishable after inadequate sampling
Explanation: Sampling below the required rate can cause spectral replicas to overlap, making different analog frequencies appear identical in the sampled data.
Reference: Standard communication systems: sampling
Question 6
Communication SystemsSampling

An anti-aliasing filter is normally placed?

  • ABefore the sampler
  • BAfter the final loudspeaker only
  • CInside the DC supply
  • DAcross the antenna mechanically
Report an error
Correct Answer: A. Before the sampler
Explanation: A low-pass anti-aliasing filter limits the input bandwidth before sampling so unwanted high-frequency components do not alias into the desired band.
Reference: Standard communication systems: sampling
Question 9
Signals & SystemsSampling

Ideal reconstruction of a properly sampled band-limited signal is theoretically performed using a?

  • AIdeal low-pass reconstruction filter
  • BHigh-pass differentiator only
  • CRectifier
  • DLimiter only
Report an error
Correct Answer: A. Ideal low-pass reconstruction filter
Explanation: After ideal impulse-train sampling above the Nyquist rate, an ideal low-pass filter can select the original baseband spectral replica.
Reference: Standard signals and systems: sampling
Question 14
Signals & SystemsSampling

If a band-limited signal is sampled above its Nyquist rate, ideal reconstruction uses sinc interpolation because the ideal reconstruction filter has a?

  • ARectangular frequency response
  • BTriangular time response only
  • CConstant impulse at every sample
  • DHigh-pass response
Report an error
Correct Answer: A. Rectangular frequency response
Explanation: An ideal brick-wall low-pass filter has a rectangular frequency response and a sinc-shaped impulse response, leading to sinc interpolation.
Reference: Standard signals and systems: sampling