Explore topic-wise MCQs in Digital Communications.

This section includes 15 Mcqs, each offering curated multiple-choice questions to sharpen your Digital Communications knowledge and support exam preparation. Choose a topic below to get started.

1.

Channels display multi-path due to

A. Scattering
B. Time delayed reflections
C. Diffraction
D. All of the mentioned
Answer» E.
2.

The channel may be affected by

A. Thermal noise
B. Interference from other signals
C. Thermal noise & Interference from other signals
D. None of the mentioned
Answer» D. None of the mentioned
3.

The average noise power of white noise is

A. 0
B. Infinity
C. 1
D. None of the mentioned
Answer» C. 1
4.

The sample from the demodulation process consists of sample which is _______ to energy of the received symbol and _____ to noise.

A. Directly and inversely proportional
B. Inversely and directly proportional
C. Both directly proportional
D. Both inversely proportional
Answer» B. Inversely and directly proportional
5.

THE_AVERAGE_NOISE_POWER_OF_WHITE_NOISE_IS?$

A. 0
B. Infinity
C. 1
D. None of the mentioned
Answer» C. 1
6.

Channels display multi-path due to$

A. Scattering
B. Time delayed reflections
C. Diffraction
D. All of the mentioned
Answer» E.
7.

The_channel_may_be_affected_by$

A. Thermal noise
B. Interference from other signals
C. Thermal noise & Interference from other signals
D. None of the mentioned
Answer» D. None of the mentioned
8.

The sample from the demodulation process consists of sample which is _______ to energy of the received symbol and _____ to noise?

A. Directly and inversely proportional
B. Inversely and directly proportional
C. Both directly proportional
D. Both inversely proportional
Answer» B. Inversely and directly proportional
9.

The composite equalizing filter is the combination of

A. Receiving and equalizing filter
B. Transmitting and equalizing filter
C. Amplifier and equalizing filter
D. None of the mentioned
Answer» B. Transmitting and equalizing filter
10.

The filter which is used to recover the pulse with less ISI is called as

A. Matched filter
B. Correlator
C. Matched filter & Correlator
D. None of the mentioned
Answer» C. Matched filter & Correlator
11.

Which are called as hard decisions?

A. Estimates of message symbol with error correcting codes
B. Estimates of message symbol without error correcting codes
C. All of the mentioned
D. None of the mentioned
Answer» C. All of the mentioned
12.

White noise has _______ power spectral density.

A. Constant
B. Variable
C. Constant & Variable
D. None of the mentioned
Answer» B. Variable
13.

Thermal noise in the communication system due to thermal electrons

A. Can be eliminated
B. Cannot be eliminated
C. Can be avoided upto some extent
D. None of the mentioned
Answer» C. Can be avoided upto some extent
14.

The causes for error performance degradation in communication systems are

A. Interference
B. Electrical noise
C. Effect of filtering
D. All of the mentioned
Answer» E.
15.

The term heterodyning refers to

A. Frequency conversion
B. Frequency mixing
C. Frequency conversion & mixing
D. None of the mentioned
Answer» D. None of the mentioned