Digital Communications

Sampling and Quantization

Question 1
Marks : +2 | -2
Pass Ratio : 100%
Which filter does not have sharp output?
Linear phase filter
Delayed symmetric filter
Linear phase & Delayed symmetric filter
None of the mentioned
Explanation:
Linear phase filter or delayed symmetric filter does not have sharp output but sampling can be done in real time.
Question 2
Marks : +2 | -2
Pass Ratio : 100%
Decreasing the data rate is called as
Aliasing
Down sampling
Up sampling
None of the mentioned
Explanation:
Decreasing the data rate is called as down sampling and increasing the data rate is called as up sampling.
Question 3
Marks : +2 | -2
Pass Ratio : 100%
Which signals are function of time?
Random signal
Deterministic signal
Random & Deterministic signal
None of the mentioned
Explanation:
Deterministic signals are function of time.
Question 4
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 5
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 6
Marks : +2 | -2
Pass Ratio : 100%
Delay element in delta modulation acts as
First order predictor
Second order predictor
Third order predictor
Fourth order predictor
Explanation:
Delay element act as first order predictor.
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%
In which mixing is easier?
Analog signal
Digital signal
Analog & Digital signal
None of the mentioned
Explanation:
Mixing of digital signals are easier than that of mixing analog signals.
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%
To avoid aliasing
Reduce the bandwidth
Cut out high frequency
Reduce the bandwidth & Cut out high frequency
None of the mentioned
Explanation:
To avoid aliasing bandwidth should be reduced and high frequency should be cut out.