MCQOPTIONS
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MCQOPTIONS
This section includes 657 Mcqs, each offering curated multiple-choice questions to sharpen your Testing Subject knowledge and support exam preparation. Choose a topic below to get started.
| 1. |
Which are the design options for anti jam communicator? |
| A. | time diversity |
| B. | frequency diversity |
| C. | special discrimination |
| D. | all of the mentioned |
| Answer» E. | |
| 2. |
Pulse jammer consists of |
| A. | pulse modulated excess band noise |
| B. | pulse modulated band-limited noise |
| C. | pulse width modulated excess band noise |
| D. | pulse width modulated band-limited noise |
| Answer» C. pulse width modulated excess band noise | |
| 3. |
Which method is better? |
| A. | to share same bandwidth |
| B. | to share different bandwidth |
| C. | to share same & different bandwidth |
| D. | none of the mentioned |
| Answer» C. to share same & different bandwidth | |
| 4. |
For any cyclic shift, the auto-correlation function is equal to |
| A. | 1/p |
| B. | -1/p |
| C. | –p |
| D. | p |
| Answer» C. –p | |
| 5. |
The sequences produced by shift register depends on |
| A. | number of stages |
| B. | feedback tap connections |
| C. | initial conditions |
| D. | all of the mentioned |
| Answer» E. | |
| 6. |
For maximal length sequence, the sequence repetition clock pulses p is given by |
| A. | 2n + 1 |
| B. | 2n -1 |
| C. | 2n |
| D. | none of the mentioned |
| Answer» C. 2n | |
| 7. |
If the initial pulse of 1000 is fed to shift register, after how many clock pulses does the sequence repeat? |
| A. | 15 |
| B. | 16 |
| C. | 14 |
| D. | 17 |
| Answer» B. 16 | |
| 8. |
A linear feedback shift register consists of |
| A. | feedback path |
| B. | modulo 2 adder |
| C. | four stage register |
| D. | all of the mentioned |
| Answer» E. | |
| 9. |
The shift register needs to be controlled by clock pulses. |
| A. | true |
| B. | false |
| Answer» B. false | |
| 10. |
The properties used for pseudorandom sequence are |
| A. | balance |
| B. | run |
| C. | correlation |
| D. | all of the mentioned |
| Answer» E. | |
| 11. |
Pseudorandom signal                  predicted. |
| A. | can be |
| B. | cannot be |
| C. | maybe |
| D. | none of the mentioned |
| Answer» B. cannot be | |
| 12. |
Which decoding method involves the evaluation by means of Fano’s algorithm? |
| A. | maximum likelihood decoding |
| B. | sequential decoding |
| C. | maximum a priori |
| D. | minimum mean square |
| Answer» C. maximum a priori | |
| 13. |
Which of the following is not an error correction and detection code? |
| A. | block code |
| B. | convolutional codes |
| C. | passive codes |
| D. | turbo codes |
| Answer» D. turbo codes | |
| 14. |
In Viterbi’s algorithm, the selected paths are regarded as |
| A. | survivors |
| B. | defenders |
| C. | destroyers |
| D. | carriers |
| Answer» B. defenders | |
| 15. |
Which of the following is not an advantage of Fano’s algorithm in comparison to Viterbi’s algorithm? |
| A. | less storage |
| B. | large constraint length |
| C. | error rate |
| D. | small delays |
| Answer» E. | |
| 16. |
Fano’s algorithm searches all the paths of trellis diagram at same time to find the most probable path. |
| A. | true |
| B. | false |
| Answer» C. | |
| 17. |
Which of the following is not an algorithm for decoding convolution codes? |
| A. | viterbi algorithm |
| B. | stack algorithm |
| C. | fano’s sequential coding |
| D. | ant colony optimization |
| Answer» E. | |
| 18. |
In comparison to stack algorithm, Fano’s algorithm is simpler. |
| A. | true |
| B. | false |
| Answer» C. | |
| 19. |
Which of the following indicates the number of input bits that the current output is dependent upon? |
| A. | constraint length |
| B. | code length |
| C. | search window |
| D. | information rate |
| Answer» B. code length | |
| 20. |
Block codes can achieve a larger coding gain than convolution coding. |
| A. | true |
| B. | false |
| Answer» C. | |
| 21. |
Which of the following is not a way to represent convolution code? |
| A. | state diagram |
| B. | trellis diagram |
| C. | tree diagram |
| D. | linear matrix |
| Answer» E. | |
| 22. |
In soft decision approach 0 represents |
| A. | certainly one |
| B. | certainly zero |
| C. | very likely zero |
| D. | could be either zero or one |
| Answer» E. | |
| 23. |
In soft decision approach 100 means? |
| A. | certainly one |
| B. | certainly zero |
| C. | very likely zero |
| D. | very likely one |
| Answer» E. | |
| 24. |
In soft decision approach what does -127 mean? |
| A. | certainly one |
| B. | certainly zero |
| C. | very likely zero |
| D. | very likely one |
| Answer» C. very likely zero | |
| 25. |
The inter leaver connected between the two decoders is used to |
| A. | remove error bursts |
| B. | scatter error bursts |
| C. | add error bursts |
| D. | none of the mentioned |
| Answer» C. add error bursts | |
| 26. |
Decoders are connected in series. |
| A. | true |
| B. | false |
| Answer» B. false | |
| 27. |
Components used for generation of turbo codes are |
| A. | inter leavers |
| B. | punching pattern |
| C. | inter leavers & punching pattern |
| D. | none of the mentioned |
| Answer» D. none of the mentioned | |
| 28. |
Turbo codes are |
| A. | forward error correction codes |
| B. | backward error correction codes |
| C. | error detection codes |
| D. | none of the mentioned |
| Answer» B. backward error correction codes | |
| 29. |
Average effective information is obtained by |
| A. | subtracting equivocation from entropy |
| B. | adding equivocation with entropy |
| C. | ratio of number of error bits by total number of bits |
| D. | none of the mentioned |
| Answer» B. adding equivocation with entropy | |
| 30. |
For a error free channel, conditional probability should be |
| A. | zero |
| B. | one |
| C. | equal to joint probability |
| D. | equal to individual probability |
| Answer» B. one | |
| 31. |
Equivocation is the |
| A. | conditional entropy |
| B. | joint entropy |
| C. | individual entropy |
| D. | none of the mentioned |
| Answer» B. joint entropy | |
| 32. |
Entropy is the measure of |
| A. | amount of information at the output |
| B. | amount of information that can be transmitted |
| C. | number of error bits from total number of bits |
| D. | none of the mentioned |
| Answer» B. amount of information that can be transmitted | |
| 33. |
Which parameter is called as Shannon limit? |
| A. | pb/n0 |
| B. | eb/n0 |
| C. | ebn0 |
| D. | none of the mentioned |
| Answer» C. ebn0 | |
| 34. |
The capacity relationship is given by |
| A. | c = w log2 ( 1+s/n ) |
| B. | c = 2w log2 ( 1+s/n ) |
| C. | c = w log2 ( 1-s/n ) |
| D. | c = w log10 ( 1+s/n ) |
| Answer» B. c = 2w log2 ( 1+s/n ) | |
| 35. |
The minimum nyquist bandwidth needed for baseband transmission of Rs symbols per second is |
| A. | rs |
| B. | 2rs |
| C. | rs/2 |
| D. | rs2 |
| Answer» D. rs2 | |
| 36. |
A function f(x) is even, when? |
| A. | f(x) = -f(x) |
| B. | f(x) = f(-x) |
| C. | f(x) = -f(x)f(-x) |
| D. | f(x) = f(x)f(-x) |
| Answer» C. f(x) = -f(x)f(-x) | |
| 37. |
Relationship between amplitude and frequency is represented by |
| A. | time-domain plot |
| B. | phase-domain plot |
| C. | frequency-domain plot |
| D. | amplitude-domain plot |
| Answer» D. amplitude-domain plot | |
| 38. |
Low frequency noise is |
| A. | flicker noise |
| B. | shot noise |
| C. | thermal noise |
| D. | partition noise |
| Answer» B. shot noise | |
| 39. |
What is the advantage of superheterodyning? |
| A. | high selectivity and sensitivity |
| B. | low bandwidth |
| C. | low adjacent channel rejection |
| D. | low fidelity |
| Answer» B. low bandwidth | |
| 40. |
Agreement between communication devices are called |
| A. | transmission medium |
| B. | channel |
| C. | protocol |
| D. | modem |
| Answer» D. modem | |
| 41. |
Noise is added to a signal |
| A. | in the channel |
| B. | at receiving antenna |
| C. | at transmitting antenna |
| D. | during regeneration of information |
| Answer» B. at receiving antenna | |
| 42. |
Sum of a periodic and aperiodic signal always be an aperiodic signal. |
| A. | true |
| B. | false |
| Answer» C. | |
| 43. |
What is the role of channel in communication system? |
| A. | acts as a medium to send message signals from transmitter to receiver |
| B. | converts one form of signal to other |
| C. | allows mixing of signals |
| D. | helps to extract original signal from incoming signal |
| Answer» B. converts one form of signal to other | |
| 44. |
Sin wave is |
| A. | aperiodic signal |
| B. | periodic signal |
| C. | random signal |
| D. | deterministic signal |
| Answer» C. random signal | |
| 45. |
What is the running time of the Huffman algorithm, if its implementation of the priority queue is done using linked lists? |
| A. | o(c) |
| B. | o(log c) |
| C. | o(c log c) |
| D. | o(c2) |
| Answer» E. | |
| 46. |
What is the running time of the Huffman encoding algorithm? |
| A. | o(c) |
| B. | o(log c) |
| C. | o(c log c) |
| D. | o( n log c) |
| Answer» D. o( n log c) | |
| 47. |
Notch is a |
| A. | high pass filter |
| B. | low pass filter |
| C. | band stop filter |
| D. | band pass filter |
| Answer» D. band pass filter | |
| 48. |
The type of encoding where no character code is the prefix of another character code is called? |
| A. | optimal encoding |
| B. | prefix encoding |
| C. | frequency encoding |
| D. | trie encoding |
| Answer» C. frequency encoding | |
| 49. |
An optimal code will always be present in a full tree. |
| A. | true |
| B. | false |
| Answer» B. false | |
| 50. |
What will be the cost of the code if character ci is at depth di and occurs at frequency fi? |
| A. | cifi |
| B. | ∫cifi |
| C. | ∑fidi |
| D. | fidi |
| Answer» D. fidi | |