Digital Communication Questions & Answers for experienced on “Sampling and Quantization”.
1. Which filter does not have sharp output?
A. Linear phase filter
B. Delayed symmetric filter
C. Linear phase & Delayed symmetric filter
D. None of the mentioned
Answer: C
Clarification: Linear phase filter or delayed symmetric filter does not have sharp output but sampling can be done in real time.
2. Using ARMA filter
A. Sampling can be done in real time
B. Gives sharp output
C. All of the mentioned
D. None of the mentioned
Answer: B
Clarification: ARMA filter gives sharp output but sampling cannot be done in real time.
3. To avoid aliasing
A. Reduce the bandwidth
B. Cut out high frequency
C. Reduce the bandwidth & Cut out high frequency
D. None of the mentioned
Answer: C
Clarification: To avoid aliasing bandwidth should be reduced and high frequency should be cut out.
4. Which requires interpolation filtering?
A. Up-sampler
B. D to A converter
C. Up-sampler & D to A converter
D. None of the mentioned
Answer: C
Clarification: Up-sampler and D to A conversion need interpolation filtering.
5. A to D conversion process uses
A. Sampler
B. Quantizer
C. Sampler & Quantizer
D. None of the mentioned
Answer: C
Clarification: A to D conversion process requires both sampler and quantizer.
6. Reconstruction filter is difficult to implement in hardware.
A. True
B. False
Answer: B
Clarification: Reconstruction filter is simpler and easy to implement in hardware.
7. Which process requires low pass filter?
A. Up-sampling
B. Down-sampling
C. Up-sampling & Down-sampling
D. None of the mentioned
Answer: C
Clarification: Up-sampling requires low pass filter after increasing the data rate and down-sampling requires low pass filter before decimation.
8. Decreasing the data rate is called as
A. Aliasing
B. Down sampling
C. Up sampling
D. None of the mentioned
Answer: B
Clarification: Decreasing the data rate is called as down sampling and increasing the data rate is called as up sampling.
9. Original signal came to be retraced from sampled version using
A. Low pass filtering
B. High pass filtering
C. Low & High pass filtering
D. None of the mentioned
Answer: A
Clarification: Original signal can be obtained from its sampled version by using low pass filtering.
10. The signal can be reconstructed
A. At Nyquist rate
B. Above Nyquist rate
C. At & above the Nyquist rate
D. None of the mentioned
Answer: C
Clarification: The signal can be reconstructed from the sampled version at or above Nyquist rate using simple low pass filtering.
11. Which device is needed for the reconstruction of signal?
A. Low pass filter
B. Equalizer
C. Low pass filter & Equalizer
D. None of the mentioned
Answer: C
Clarification: Equalizer followed by a low pass filter is necessary for reconstruction of a signal from its sampled version.
Digital Communication for experienced,