Diversity Technique and Rake Receivers

Question 1
Marks : +2 | -2
Pass Ratio : 100%
Which signalling scheme is preferred for fading channel?
Frequency based modulation
Phase based modulation
Frequency & Phase based modulation
None of the mentioned
Explanation:
Frequency based modulation and phase based modulation is preferable for fading channel than amplitude based modulation.
Question 2
Marks : +2 | -2
Pass Ratio : 100%
Diversity technique is applied at
Base station
Mobile receiver
Base station & Mobile receiver
None of the mentioned
Explanation:
Diversity technique can be applied at both base station and at mobile receivers.
Question 3
Marks : +2 | -2
Pass Ratio : 100%
What are the modes of adaptive equalizer?
Training mode
Tracking mode
Training & Tracking mode
None of the mentioned
Explanation:
Adaptive equalizer operates on two modes – training mode and tracking mode.
Question 4
Marks : +2 | -2
Pass Ratio : 100%
Interleaving does
Forward error correction
Backward error correction
Forward & Backward error correction
None of the mentioned
Explanation:
Inter leaver does forward error correction.
Question 5
Marks : +2 | -2
Pass Ratio : 100%
Diversity technique
Provides significant link improvement
Needs training overhead
All of the mentioned
None of the mentioned
Explanation:
Diversity technique does not require training overhead at the transmitter and also provides significant link performance.
Question 6
Marks : +2 | -2
Pass Ratio : 100%
Diversity technique is used for combating
Fading
Error bursts
Co-channel interference
All of the mentioned
Explanation:
Diversity technique is a common method used for combating fading, co-channel interference and error bursts.
Question 7
Marks : +2 | -2
Pass Ratio : 100%
Which is more effective and commonly preferred technique?
Time diversity
Spatial diversity
Frequency diversity
None of the mentioned
Explanation:
Most commonly used and more effective diversity technique is spatial diversity technique.
Question 8
Marks : +2 | -2
Pass Ratio : 100%
The technique for combining diversity signals are
Feedback
Maximal ratio
Equal gain
All of the mentioned
Explanation:
The most common techniques used for combining diversity signals are selection, feedback, maximal ratio and equal gain.
Question 9
Marks : +2 | -2
Pass Ratio : 100%
Rake receiver does
Counter effects multi-path fading
Resembles equalizer
Resembles equalizer & Counter effects multi-path fading
None of the mentioned
Explanation:
Rake receiver resembles equalizers and it is used to counter the effects of multipath fading and is also used to exploit the path diversity.
Question 10
Marks : +2 | -2
Pass Ratio : 100%
Uncorrelated fading occurs when
Time span is small
Time span is large
Does not depend on time span
None of the mentioned
Explanation:
As the time span increases, the fading is more uncorrelated and effectiveness also increases.