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%
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 3
Marks : +2 | -2
Pass Ratio : 100%
Transmission media used in low frequency band are
Air
Water
Copper cable
All of the mentioned
Explanation:
Air, water and copper cable can be used as transmission media in low frequency band communication.
Question 4
Marks : +2 | -2
Pass Ratio : 100%
In flat top sampling scheme, ______ is kept constant after sampling.
Amplitude
Phase
Frequency
Time period
Explanation:
In flat top sampling scheme, the amplitude is kept constant after sampling.
Question 5
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 6
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 7
Marks : +2 | -2
Pass Ratio : 100%
Wired channels are
Lossy
Lossless
Lossy & Lossless
None of the mentioned
Explanation:
Wired channels are lossy channels.
Question 8
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.
Question 9
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 10
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.