Digital Communications

Digital Communication System

Question 1
Marks : +2 | -2
Pass Ratio : 100%
The equivalent temperature in a receiver design must be kept
Low
High
Does not affect the receiver
None of the mentioned
Explanation:
The equivalent temperature is the function of the receiver design and it must be always kept low.
Question 2
Marks : +2 | -2
Pass Ratio : 100%
Which are the common transmission media used in digital communication system?
Coaxial cable
Twisted copper cable
Radio frequency bands
All of the mentioned
Explanation:
Some of the commonly used physical transmission media are twisted copper cable, good quality coaxial cable and radio frequency bands.
Question 3
Marks : +2 | -2
Pass Ratio : 100%
The basic transmission-reception system is a ______ system.
Two block system
Three block system
Four block system
None of the mentioned
Explanation:
The basic transmission-reception consists of three blocks – transmitter, transmission medium, receiver.
Question 4
Marks : +2 | -2
Pass Ratio : 100%
Which is practically realizable?
A train of pulses
Impulse train
All of the mentioned
None of the mentioned
Explanation:
A train of pulses with narrow bandwidth is realizable than the impulse train.
Question 5
Marks : +2 | -2
Pass Ratio : 100%
Ground wave communication occurs in
Low frequency band
Medium frequency band
Low & Medium frequency band
None of the mentioned
Explanation:
Ground wave communication can take place in both low frequency and medium frequency bands.
Question 6
Marks : +2 | -2
Pass Ratio : 100%
Matched filter can also be used as least squares estimator.
True
False
Explanation:
A matched filter can also be used as a least squares estimator.
Question 7
Marks : +2 | -2
Pass Ratio : 100%
Transmission media used for medium frequency band are
Coaxial cable
Copper cable
Optical fiber
All of the mentioned
Explanation:
For medium frequency band communication air and copper cable can only be used as a transmission medium.
Question 8
Marks : +2 | -2
Pass Ratio : 100%
Sampling theorem is used for converting
Continuous time signal to discrete
Discrete to continuous time signal
Continuous time signal to discrete & vice versa
None of the mentioned
Explanation:
Sampling theorem is used for converting continuous time signal to discrete type signal and vice versa.
Question 9
Marks : +2 | -2
Pass Ratio : 100%
Modulation channel consists of
Amplifier
Signal processing units
Amplifier & Signal processing units
None of the mentioned
Explanation:
When information is transmitted through large distance it must be amplified. Modulation channel consists of an amplifier and other signal processing units.
Question 10
Marks : +2 | -2
Pass Ratio : 100%
Modulation channel does not accept an analog input signal.
True
False
Explanation:
Modulation channel accepts analog signal as input and delivers another version of modulated signal as analog waveform.