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Free download in PDF Sampling Theorem Objective Type Questions and Answers for competitive exams. These short objective type questions with answers are very important for Board exams as well as competitive exams. These short solved questions or quizzes are provided by Gkseries.
(21)
Drawback of using PAM method is
[A]
Due to varying amplitude of carrier, it is difficult to remove noise at receiver
[B]
Bandwidth is very large as compared to modulating signal
[C]
Varying amplitude of carrier varies the peak power required for transmission
[D]
All of the above
(22)
In Pulse time modulation (PTM),
[A]
Pulse width modulation and pulse position modulation are the types of PTM
[B]
Amplitude of the carrier is constant
[C]
Position or width of the carrier varies with modulating signal
[D]
All of the above
(23)
In different types of Pulse Width Modulation,
[A]
Centre of the pulse is kept constant
[B]
Leading edge of the pulse is kept constant
[C]
Tail edge of the pulse is kept constant
[D]
All of the above
(24)
In pulse width modulation,
[A]
Amplitude of the carrier pulse is varied
[B]
Instantaneous power at the transmitter is constant
[C]
Synchronization is not required between transmitter and receiver
[D]
None of the above
Answer: Synchronization is not required between transmitter and receiver
(25)
In PWM signal reception, the Schmitt trigger circuit is used
[A]
To produce ramp signal
[B]
For synchronization
[C]
To remove noise
[D]
None of the above
(26)
In Pulse Position Modulation, the drawbacks are
[A]
Large bandwidth is required as compared to PAM
[B]
Synchronization is required between transmitter and receiver
[C]
None of the above
[D]
Both a and b
(27)
As per sampling theorem –
[A]
Twice each cycle of its highest frequency
[B]
Guard time should be as large as possible
[C]
The signal should be sampled at least twice each cycle of its lowest frequency
[D]
Nyquist rate should be as low as possible
Answer: Twice each cycle of its highest frequency
(28)
In communication the sampling technique leads to –
[A]
Higher speed of communication
[B]
cheaper equipment
[C]
Higher efficiency
[D]
All of the above
Answer: Higher speed of communication
(29)
Impulse modulation systems, The number of samples required to ensure no loss of information is given by –
[A]
Parsevals theorem
[B]
Fourier transmission
[C]
Nyquist theorem
[D]
None of the these
(30)
If the sampling time is less than the Nyquist interval :
[A]
Simpler filters can be used to obtain the original signal
[B]
Channel Capacity increases
[C]
Bandwidth increases
[D]
Guard time becomes less
Answer: Simpler filters can be used to obtain the original signal
31
The scaling of a sequence x[n] by a factor α is given by
[A]
y[n] = α [x[n]]2
[B]
y[n] = α x[n2]
[C]
y[n] = α x[n]
[D]
y[n] = x[n]x[-n]
32
Causal systems are the systems in which
[A]
The output of the system depends on the present and the past inputs
[B]
The output of the system depends only on the present inputs
[C]
The output of the system depends only on the past inputs
[D]
The output of the system depends on the present input as well as the previous outputs
Answer: The output of the system depends on the present and the past inputs
33
Roll-off factor is
[A]
The bandwidth occupied beyond the Nyquist Bandwidth of the filter
[B]
The performance of the filter or device
[C]
Aliasing effect
[D]
None of the above
Answer: The bandwidth occupied beyond the Nyquist Bandwidth of the filter
34
A signal x[n] is anti symmetric or odd when
[A]
x[-n] = x[n] • x[n]
[B]
x[n] = -x[n]
[C]
x[n] = [x[n]]2
[D]
x[-n] = -x[n]
35
A signal of maximum frequency of 10 kHz is sampled at Nyquist rate. The time interval between two successive sample is –
[A]
50 µs
[B]
100 µs
[C]
1000 µs
[D]
5 µs
(16)
Time reversal of a discrete time signal refers to
[A]
y[n] = x[-n+k]
[B]
y[n] = x[-n]
[C]
y[n] = x[-n-k]
[D]
y[n] = x[n-k]
37
Time shifting of discrete time signal means
[A]
y[n] = x[n-k]
[B]
y[n] = x[-n-k]
[C]
y[n] = -x[n-k]
[D]
y[n] = x[n+k]
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