Digital Communications

Digital Communication System

Question 1
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 2
Marks : +2 | -2
Pass Ratio : 100%
Which corrects the sampling time problem in a digital system?
Interpolator
Decimator
Equalizer
Filter
Explanation:
Interpolator corrects the sampling time problem using discrete time processing.
Question 3
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 4
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 5
Marks : +2 | -2
Pass Ratio : 100%
Wired channels are
Lossy
Lossless
Lossy & Lossless
None of the mentioned
Explanation:
Wired channels are lossy channels.
Question 6
Marks : +2 | -2
Pass Ratio : 100%
Matched filter technique is used to
Increase SNR
Decrease SNR
SNR is not affected
None of the mentioned
Explanation:
Matched filter technique is a demodulation process used to increase SNR.
Question 7
Marks : +2 | -2
Pass Ratio : 100%
What are the main features of a transmitter?
Higher clock speed
Linear power amplifier
Directional antennas
All of the mentioned
Explanation:
Some of the main features which make the transmitter complex are higher clock speed, higher transmit power, directional antennas and need for a linear amplifier.
Question 8
Marks : +2 | -2
Pass Ratio : 100%
If operating frequency bands are higher ______ is available.
Smaller bandwidth
Larger bandwidth
Smaller & Larger bandwidth
Cannot be determined
Explanation:
Larger bandwidth is available when operating frequency bands are higher.
Question 9
Marks : +2 | -2
Pass Ratio : 100%
What are the main features of a receiver?
Synchronization
Multiple parallel receiver chain
Synchronization & Multiple parallel receiver chain
None of the mentioned
Explanation:
The main features of a receiver which increases its complexity are synchronization of carrier, phase, and timing and multiple parallel receiver chain.
Question 10
Marks : +2 | -2
Pass Ratio : 100%
A signal can be recovered from its sample by using
Low pass filter
High pass filter
Band pass filter
Band stop filter
Explanation:
A signal can be recovered from its sampled version by using an ideal low pass filter.