Digital Communications

Sampling and Quantization

Question 1
Marks : +2 | -2
Pass Ratio : 100%
Which process requires low pass filter?
Up-sampling
Down-sampling
Up-sampling & Down-sampling
None of the mentioned
Explanation:
Up-sampling requires low pass filter after increasing the data rate and down-sampling requires low pass filter before decimation.
Question 2
Marks : +2 | -2
Pass Ratio : 100%
The signal can be reconstructed
At Nyquist rate
Above Nyquist rate
At & above the Nyquist rate
None of the mentioned
Explanation:
The signal can be reconstructed from the sampled version at or above Nyquist rate using simple low pass filtering.
Question 3
Marks : +2 | -2
Pass Ratio : 100%
Shot noise occurs in
Transistors
Valves
Transistors & Valves
None of the mentioned
Explanation:
Shot noise occurs in both valves and transistors.
Question 4
Marks : +2 | -2
Pass Ratio : 100%
Auto-correlation function is a
Even function
Odd function
Even & Odd function
None of the mentioned
Explanation:
Auto-correlation function is an even function of time.
Question 5
Marks : +2 | -2
Pass Ratio : 100%
Source coding reduces
Redundancy
Average bit rate
Redundancy & Average bit rate
None of the mentioned
Explanation:
Source coding reduces both average bit rate and reduces redundancy.
Question 6
Marks : +2 | -2
Pass Ratio : 100%
Which requires interpolation filtering?
Up-sampler
D to A converter
Up-sampler & D to A converter
None of the mentioned
Explanation:
Up-sampler and D to A conversion need interpolation filtering.
Question 7
Marks : +2 | -2
Pass Ratio : 100%
Original signal came to be retraced from sampled version using
Low pass filtering
High pass filtering
Low & High pass filtering
None of the mentioned
Explanation:
Original signal can be obtained from its sampled version by using low pass filtering.
Question 8
Marks : +2 | -2
Pass Ratio : 100%
Non uniform quantization includes
Compression
Expansion
Compression & Expansion
None of the mentioned
Explanation:
Compression and expansion give the feature of non uniform quantization.
Question 9
Marks : +2 | -2
Pass Ratio : 100%
The quantization will be finer when
Smaller the number of discrete amplitudes
Larger the number of discrete amplitudes
Does not depend on amplitudes
None of the mentioned
Explanation:
Larger the number of discrete amplitudes, finer will be the quantization.
Question 10
Marks : +2 | -2
Pass Ratio : 100%
Reconstruction filter is difficult to implement in hardware.
True
False
Explanation:
Reconstruction filter is simpler and easy to implement in hardware.