Electrical measurements/Digital Communications MCQs set-15 Sample Test,Sample questions

Question:
 Scintillation describes the fading caused by

1.Atmospheric changes

2.Physical changes

3.Thermal noise

4.Propagating effects


Question:
A rake receiver uses multiple

1.Delay circuits

2.Correlators

3.Detectors

4.None of the mentioned


Question:
Block fading occurs in

1.Frequency domain

2.Time domain

3.Frequency & Time domain

4.None of the mentioned


Question:
Channel’s time spreading properties are

1.Coherence bandwidth

2.Signal dispersion

3.Coherence bandwidth & Signal dispersion

4.None of the mentioned


Question:
Coherence time is _______ to Doppler spread.

1.Directly proportional

2.Inversely proportional

3.Not dependent

4.None of the mentioned


Question:
Diversity technique is applied at

1.Base station

2.Mobile receiver

3.Base station & Mobile receiver

4.None of the mentioned


Question:
Diversity technique is used for combating

1.Fading

2.Error bursts

3.Co-channel interference

4.All of the mentioned


Question:
DSA protocol is based on

1.Discrete logarithm problem

2.Continuous logarithm problem

3.Discrete & Continuous logarithm problem

4.None of the mentioned


Question:
Fading channel has memory.

1.True

2.False


Question:
Fast fading can be minimized by

1.Robust modulation

2.Coding and interleaving

3.Robust modulation, Coding and interleaving

4.None of the mentioned


Question:
Flat fading can be avoided or stopped by

1.Error coding

2.Equalization

3.Adaptive bit loading

4.All of the mentioned


Question:
Frequency tracking loop can minimize irreducible error rate by using

1.GMSK

2.DMSK

3.MSK

4.QAM


Question:
How can frequency selective distortion be minimized?

1.By using pilot signal

2.By adaptive equalization

3.By spread spectrum

4. All of the mentioned


Question:
How can slow fading be minimized?

1.By diversity technique

2.Error correcting codes

3.By diversity technique & Error correcting codes

4.None of the mentioned


Question:
If coherence bandwidth is smaller than the bandwidth of the signal, _____ fading occurs.

1.Flat

2.Frequency selective

3.Fast fading

4.Time selective


Question:
If delay time is greater than symbol time, _______ fading occurs.

1.Frequency selective

2.Time selective

3.Frequency non selective

4.None of the mentioned


Question:
If delay time is lesser than symbol time, ______ fading occurs.

1.Frequency non selective

2.Flat

3.Frequency non selective & Flat

4.None of the mentioned


Question:
If signalling rate is less than fading rate, _____ fading occurs.

1.Slow

2.Fast

3.Time selective

4. None of the mentioned


Question:
In hash function output length is fixed.

1.True

2.False


Question:
Information reliability depends on

1.Magnitude of each component

2.Time of arrival of each component

3.Magnitude & Time of arrival of each component

4.None of the mentioned


Question:
Interleaving does

1.Forward error correction

2.Backward error correction

3.Forward & Backward error correction

4.None of the mentioned


Question:
Large scale fading refers the attenuation in

1.Amplitude

2.Phase

3.Signal power

4.None of the mentioned


Question:
Minimum time required for magnitude change or phase change is called as

1.Shift time

2.Coherence time

3.Delay time

4.None of the mentioned


Question:
Multiple isolated peaks in multipath components is called as

1.Fingers

2.Returns

3.Fingers & Returns

4.None of the mentioned


Question:
Rake receiver does

1.Counter effects multi-path fading

2.Resembles equalizer

3.Resembles equalizer & Counter effects multi-path fading

4.None of the mentioned


Question:
Rake receivers are used in

1.Radio astronomy

2.CDMA

3.W-CDMA

4.All of the mentioned


Question:
Small scale fading manifests due to

1.Signal dispersion

2.Time variant behavior

3.Signal dispersion & Time variant behavior

4.None of the mentioned


Question:
Small scale fading occurs due to

1.Doppler shift

2.Time delay

3.Doppler shift & Time delay

4.None of the mentioned


Question:
Small scale refers to changes in

1.Amplitude

2.Phase

3.Amplitude & Phase

4.None of the mentioned


Question:
The decision feedback equalizer has a linear traversal filter which is

1.Feed forward section

2. Feedback section

3.Feed forward section & Feedback section

4.None of the mentioned


Question:
The digital signature provides authentication to the

1.Sender

2.Message

3.Sender & Message

4.None of the mentioned


Question:
The effect of Doppler shift can be counterattacked by

1.OFDM

2.By using two receivers with separate antennas

3.By using diversity receiver

4.All of the mentioned


Question:
The hash function

1.Is collision free

2.Has manageable collision

3.Has high unmanageable level of collision

4.None of the mentioned


Question:
The inter-leaver is more effective if the vehicle is

1.Fast

2.Slow

3.Fast & Slow

4. None of the mentioned


Question:
The ISI and adjacent channel interference is removed by

1.Cancelling filter

2.Port processing equalizer

3.Cancelling filter & Port processing equalizer

4.None of the mentioned


Question:
The parameters used to describe large scale fading are

1.Reference distance

2.Path loss exponent

3.Standard deviation of random variable

4.All of the mentioned


Question:
The rake receivers functions are similar to

1.Equalizer

2.Matched filter

3.Equalizer & Matched filter

4.None of the mentioned


Question:
The received power is attenuated by a factor called

1.Path loss

2.Free space loss

3.Path & Free space loss

4.None of the mentioned


Question:
The technique for combining diversity signals are

1.Feedback

2.Maximal ratio

3.Equal gain

4.All of the mentioned


Question:
Uncorrelated fading occurs when

1.Time span is small

2.Time span is large

3.Does not depend on time span

4.None of the mentioned


Question:
What are the modes of adaptive equalizer?

1.Training mode

2.Tracking mode

3. Training & Tracking mode

4.None of the mentioned


Question:
What are the types of small scale fading that occurs due to Doppler shift?

1.Slow fading

2.Fast fading

3.Slow & Fast fading

4.None of the mentioned


Question:
What is the source for performance degradation?

1.Thermal noise

2.Man made noise

3.Natural noise

4.All of the mentioned


Question:
When a user’s moving, the user’s velocity causes shift in frequency. This is called as

1.Doppler shift

2.Frequency shift

3.Velocity shift

4.None of the mentioned


Question:
When channel coherence bandwidth is greater than the transmitted signal bandwidth ______ occurs.

1.Time selective

2.Frequency selective

3.Frequency non selective

4.None of the mentioned


Question:
When channel coherence time is less than the time duration of a transmission symbol, then ______ fading occurs.

1.Fast

2.Slow

3.Time selective

4. None of the mentioned


Question:
When transmitter and receiver moves towards each other, the magnitude of frequency shift is

1.Positive

2.Negative

3.Zero

4.Infinity


Question:
Which is more effective and commonly preferred technique?

1.Time diversity

2.Spatial diversity

3.Frequency diversity

4.None of the mentioned


Question:
Which should be used first to decrypt?

1.Public key

2.Private key

3.Public & Private key

4.None of the mentioned


Question:
Which signalling scheme is preferred for fading channel?

1.Frequency based modulation

2.Phase based modulation

3.Frequency & Phase based modulation

4.None of the mentioned


More MCQS

  1. Electrical Measurement MCQ Question Set 1
  2. Electrical Measurement MCQ Question Set 2
  3. Electrical Measurement MCQ Question Set 3
  4. Electrical Measurement MCQ Question Set 4
  5. Electrical Measurement MCQ Question Set 5
  6. Electrical Measurement MCQ Question Set 6
  7. Electrical Measurement MCQ Question Set 7
  8. Electrical Measurement MCQ Question Set 8
  9. Electrical Measurement MCQ Question Set 9
  10. Electrical Measurement MCQ Question Set 10
  11. Electrical Measurement MCQ Question Set 11
  12. Electrical Measurement MCQ Question Set 12
  13. Electrical Measurement MCQ Question Set 13
  14. Electrical Measurement MCQ Question Set 14
  15. Electrical Measurement MCQ Question Set 15
  16. Electrical Measurement MCQ Question Set 16
  17. Electrical Measurement MCQ Question Set 17
  18. Digital Communications MCQs set-1
  19. Digital Communications MCQs set-2
  20. Digital Communications MCQs set-3
  21. Digital Communications MCQs set-4
  22. Digital Communications MCQs set-5
  23. Digital Communications MCQs set-6
  24. Digital Communications MCQs set-7
  25. Digital Communications MCQs set-8
  26. Digital Communications MCQs set-9
  27. Digital Communications MCQs set-10
  28. Digital Communications MCQs set-11
  29. Digital Communications MCQs set-12
  30. Digital Communications MCQs set-13
  31. Digital Communications MCQs set-14
  32. Digital Communications MCQs set-15
  33. Digital Communications MCQs set-16
  34. Digital Communications MCQs set-17
Search
R4R Team
R4Rin Top Tutorials are Core Java,Hibernate ,Spring,Sturts.The content on R4R.in website is done by expert team not only with the help of books but along with the strong professional knowledge in all context like coding,designing, marketing,etc!