Effects of Fading and Decision Theory

Question 1
Marks : +2 | -2
Pass Ratio : 100%
Channel noise is
Additive
White and stationary
Has infinite bandwidth
All of the mentioned
Explanation:
Channel noise is stationary, additive and white with infinite bandwidth.
Question 2
Marks : +2 | -2
Pass Ratio : 100%
Fast fading can be minimized by
Robust modulation
Coding and interleaving
Robust modulation, Coding and interleaving
None of the mentioned
Explanation:
Fast fading can be minimized by using coding and interleaving, by using robust modulation and by introducing signal redundancy to increase signalling rate.
Question 3
Marks : +2 | -2
Pass Ratio : 100%
How can frequency selective distortion be minimized?
By using pilot signal
By adaptive equalization
By spread spectrum
All of the mentioned
Explanation:
Frequency selective distortion can be minimized by using adaptive equalization, by using spread spectrum, by using pilot signal and also by using orthogonal FDM modulation.
Question 4
Marks : +2 | -2
Pass Ratio : 100%
Which noise component plays a role in decision making?
Relevant noise
Non relevant noise
Relevant & Non relevant noise
None of the mentioned
Explanation:
Only the relevant noise components play an important role in decision making. It does not depend on non relevant noise components.
Question 5
Marks : +2 | -2
Pass Ratio : 100%
The inter-leaver is more effective if the vehicle is
Fast
Slow
Fast & Slow
None of the mentioned
Explanation:
The inter-leaver is more effective in fast running vehicles.
Question 6
Marks : +2 | -2
Pass Ratio : 100%
The ISI and adjacent channel interference is removed by
Cancelling filter
Port processing equalizer
Cancelling filter & Port processing equalizer
None of the mentioned
Explanation:
The known ISI which is introduced deliberately and the adjacent channel interference is removed by cancelling filter and post processing equalizer.
Question 7
Marks : +2 | -2
Pass Ratio : 100%
How can slow fading be minimized?
By diversity technique
Error correcting codes
By diversity technique & Error correcting codes
None of the mentioned
Explanation:
Slow fading can be minimized by using error correcting codes and also by using diversity technique to get additional uncorrelated estimates of a signal.
Question 8
Marks : +2 | -2
Pass Ratio : 100%
Fading channel has memory.
True
False
Explanation:
Fading channel has memory and the received samples are correlated with each other in time.
Question 9
Marks : +2 | -2
Pass Ratio : 100%
Decision making needs
Priors
Likelihoods
Priors & Likelihoods
None of the mentioned
Explanation:
Decision making needs both priors and likelihoods and Bayes decision rule combines them to achieve minimum probability of error.
Question 10
Marks : +2 | -2
Pass Ratio : 100%
The decision feedback equalizer has a linear traversal filter which is
Feed forward section
Feedback section
Feed forward section & Feedback section
None of the mentioned
Explanation:
The decision feedback filter has a feed forward section which is a linear traversal filter.