wayground logo

Free Printable Worksheets

Font size

S
M
L
XL
Worksheets

CE QUIZ

Total questions: 70

Worksheet time: 55mins

Name
Class
Date
1.

In digital modulation, the carrier signal used is digital.

a)

True

b)

False

2.

Which is called as on-off keying?

a)

Amplitude shift keying

b)

Frequency shift keying

c)

Phase shift keying

3.

QPSK uses a phase shift of

a)

180

b)

90

c)

45

d)

30

4.

BPSK uses a phase shift of

a)

180

b)

90

c)

45

d)

30

5.

BPSK system modulates at the rate of

a)

1 bit/ symbol

b)

2 bit/ symbol

c)

4 bit/ symbol

d)

8 bit/ symbol

6.

QPSK system modulates at the rate of

a)

1 bit/ symbol

b)

2 bit/ symbol

c)

4 bit/ symbol

d)

8 bit/ symbol

7.

In coherent detection of signals

a)

Local carrier is generated

b)

Carrier of frequency and phase as same as transmitted carrier is generated

c)

The carrier is in synchronization with modulated carrier

d)

All the above

8.

In binary data transmission DPSK is preferred to PSK because

a)

a coherent carrier is not required to be generated at the receiver

b)

for a given energy per bit, the probability of error is less

c)

the 180 phase shifts of the carrier are unimportant

d)

more protection is provided against impulse noise

9.

The method in which small amount of controlled ISI is introduced into the data stream is called as

a)

Correlative coding

b)

Duobinary signalling

c)

Both (1) & (2)

d)

none

10.

The method using which the error propagation in duobinary signaling can be avoided is

a)

Filtering

b)

Precoding

c)

Postcoding

d)

None

11.

The time interval over which the received signal may be sampled without error may be explained by

a)

Width of eye opening of eye pattern

b)

Rate of closure of eye of eye pattern

c)

Height of the eye opening of eye pattern

d)

All of the above

12.

In _______ the phase and amplitude of the carrier signal is varied in accordance with the information signal

a)

ASK

b)

FSK

c)

QAM

d)

QPSK

13.

Phase reversal keying is known as

a)

BPSK

b)

BFSK

c)

QPSK

d)

QAM

14.

Identify the non-coherent technique

a)

BPSK

b)

DPSK

c)

BOTH (1) & (2)

d)

NONE

15.

In 16 QAM constellation diagram , each signal point represent a

a)

Dibit

b)

Tribit

c)

Quadbit

d)

Pentabit

16.

The number of points in the constellation of an 8 PSK modulation is _______ the number of points for an 8 QAM

a)

Greater than

b)

Lesser than

c)

Equal to

d)

none

17.

In binary data transmission DPSK is preferred to PSK because

a)

the 180 degree phase shifts of the carrier are unimportant

b)

more protection is provided against impulse noise

c)

for a given energy per bit, the probability of error is less

d)

a coherent carrier is not required to be generated at the receiver

18.

A DPSK wave is obtained by

a)

BPSK

b)

Differential encoding followed by BPSK

c)

Differential Encoding

d)

none

19.

QAM uses ______ as the dimensions.

a)

In phase

b)

Quadrature

c)

In phase & Quadrature

d)

none

20.

Successive phase difference between carriers in M-ARY PSK is :

a)

ϕ=2π / 3M​

b)

ϕ=2π​ / M

c)

ϕ=π​ / M

d)

ϕ=M​ / 2π

21.

Energy per symbol (Es) and Energy per bit (Eb) are related as

a)

Es​=Eb​log2​M

b)

Es​=2Eb​log2​M

c)

Es​=2Eb​​log2​M

d)

Es​=log2​MEb

22.

In a dibit modulation ,the number of points in the constellation is

a)

1

b)

2

c)

4

d)

8

23.

DPSK uses coherent form of PSK. State whether True or False.

a)

true

b)

false

24.

In which system, bit stream is portioned into even and odd stream?

a)

BPSK

b)

BFSK

c)

QPSK

d)

QAM

25.

In DPSK technique, the technique used to encode bits is

a)

Differential code

b)

Uni polar RZ format

c)

bi polar RZ format

d)

Manchester format

26.

If the number of possible message points is 16, then the value of n is

a)

4

b)

5

c)

6

d)

8

27.

For M equally likely messages, the average amount of information H is

a)

H = log10M

b)

H = log2M

c)

H = log10M2

d)

H = 2log10M

28.

The channel capacity is

a)

The maximum information transmitted by one symbol over the channel

b)

Information contained in a signal

c)

The amplitude of the modulated signal

d)

all the above

29.

Code rate r, k information bits and n as total bits, is defined as

a)

r = k/n

b)

k = n/r

c)

r = k * n

d)

n = r * k

30.

Information rate is defined as

a)

Average number of bits of information per second

b)

Information per unit time

c)

rH

d)

All of the above

31.

In discrete memoryless source, the current letter produced by a source is statistically independent of _____

a)

Past output

b)

Future output

c)

Past output & Future output

d)

none

32.

In channel coding theorem, channel capacity decides the _________permissible rate at which error free transmission is possible.

a)

Maximum

b)

Minimum

c)

Constant

d)

None of the above

33.

Which type of compression ensures that all of the data is kept?

a)

Lossless

b)

Lossy

34.

The relation between entropy and mutual information is

a)

I(X;Y) = H(X) – H(X/Y)

b)

I(X;Y) = H(X/Y) – H(Y/X)

c)

I(X;Y) = H(Y) – H(X)

d)

I(X;Y) = H(Y) – H(X)

35.

The unit of average mutual information is

a)

Bits

b)

Bytes

c)

Bits per symbol

d)

Bytes per symbol

36.

Average information is termed as-------------

(a)  

37.

Reliable communication is possible only data rate stays below channel capacity.The theorem is

a)

channel coding theorem

b)

source coding theorem

38.

To reliably store the information generated by some

random source X, you need no more/less than, on the average, H(X) bits for each outcome. The statement is related to --------------theorem

a)

channel coding

b)

source coding

39.

When X and Y are statistically independent, then I (x,y) is

a)

1

b)

0

c)

infinite

d)

cant be determined

40.

The mutual information

a)

Is symmetric

b)

Always non negative

c)

Both a and b are correct

d)

None of the above

41.

Huffman coding technique is adopted for constructing the source code with ________ redundancy.

a)

Maximum

b)

Constant

c)

Minimum

d)

Unpredictable

42.

Which one of the following is not correct ?

a)

Source coding theorem L ≥ H

b)

Channel coding theorem C≥R

c)

Channel coding theorem R≤ C

d)

Source coding theorem L ≤ H

43.

The received code contains an error if the syndrome vector is

a)

Zero

b)

Non zero

c)

Infinity

d)

None of the mentioned

44.

Syndrome is calculated by

a)

HT/r

b)

rHT

c)

rH

d)

None of the mentioned

45.

The number of k bit shift over which a single information bit influences the encoder output is given by

a)

Code rate

b)

Constraint length

c)

Code length

d)

Code weight

46.

Viterbi algorithm performs ____________ decoding of convolutional codes.

a)

Maximum likelihood

b)

Maximum a posteriori

c)

Minimum square

d)

Minimum mean square

47.

The paths that are retained by Viterbi algorithm are_____

a)

survivor

b)

metric

c)

Height

d)

carrier

48.

Calculate entropy for the probabilities 0.4,0.2,0.2,0.1,0.1

a)

2.52 bits/msg

b)

2.42 bits/msg

c)

2.32 bits/msg

d)

2.12 bits/msg

49.

In cyclic code, if the remainder is x2 then the syndrome is

a)

010

b)

100

c)

011

d)

111

50.

In cyclic code, if the remainder is x2 + x then the syndrome is

a)

100

b)

110

c)

111

d)

011

51.

Hamming distance between 1010 and 0110 is

a)

2

b)

4

c)

3

d)

1

52.

Hamming distance between 0110 and 0110 is

a)

0

b)

1

c)

2

d)

4

53.

If coding efficiency ŋ=1, then efficiency is

a)

50%

b)

100%

c)

75%

d)

0%

54.

Code redundancy can be calculated as

a)

ŋ -1

b)

1-ŋ

c)

ŋ +1

d)

ŋ

55.

convolutional code decoding is called

(a)  

56.

cyclic code decoding is called

(a)  

57.

In spread spectrum technique, the multiple users are assigned

a)

Same spectrum and same PN code

b)

Same spectrum and different PN code

c)

Different spectrum and different PN code

d)

Different spectrum and same PN code

58.

The period of a PN sequence produced by a linear m stage shift register cannot exceed _____ symbols.

a)

2m

b)

m

c)

2m

d)

2m -1

59.

DSSS system spreads the baseband signal by ________ the baseband pulses with a pseudo noise sequence.

a)

Adding

b)

Subtracting

c)

Multiplying

d)

Dividing

60.

In fast frequency hopping,

a)

hopping rate is more than the information symbol rate.

b)

hopping rate is less than the information symbol rate.

c)

hopping rate is equal to the information symbol rate

d)

None

61.

The frequency hopping system uses ______ modulation scheme.

a)

FSK

b)

MFSK

c)

BPSK

d)

PSK

62.

The direct sequence system uses ______ modulation scheme.

a)

FSK

b)

MFSK

c)

BPSK

d)

BFSK

63.

The properties used for pseudorandom sequence are

a)

Balance

b)

Run

c)

Correlation

d)

All of the mentioned

64.

Multiple access schemes are used to allow ________ mobile users to share simultaneously a finite amount of radio spectrum

a)

Many

b)

One

c)

Two

d)

Eight

65.

Which sequence holds the property of periodicity?

a)

PN sequence

b)

m sequence

c)

maximum length sequence

d)

all of these

66.

__________ are utilized to allow synchronization of the receivers between different slots and frames.

a)

Preamble

b)

Data

c)

Guard bits

d)

Trail bits

67.

Why spread spectrum technique is inefficient for a single user?

a)

Fixed transmission bandwidth

b)

Small transmission bandwidth

c)

Large transmission bandwidth

d)

Fixed null bandwidth

68.

Which of the following is not a characteristic of PN sequence?

a)

Nearly equal number of 0s and1s

b)

Low correlation between shifted version of sequence

c)

Non deterministic

d)

Low cross-correlation between any two sequences

69.

If the number of flipflops used in the shift register is 4, then length of PN sequence is

a)

14

b)

15

c)

16

d)

17

70.

If the number of flipflops used in the shift register is 8, then length of PN sequence is

a)

255

b)

256

c)

257

d)

259

Similar Resources on Wayground

SpongeBob SquarePants

66 questions

SpongeBob SquarePants

quiz

Worksheet

•

KG - Professional Dev...

Chapter 5: Infection Control - Principles & Practices

75 questions

Chapter 5: Infection Control - Principles & Practices

quiz

Worksheet

•

9th Grade - Professio...

DAA Tutorial-1

70 questions

DAA Tutorial-1

quiz

Worksheet

•

University

Genetics Unit 1

75 questions

Genetics Unit 1

quiz

Worksheet

•

University

Randomness

69 questions

Randomness

quiz

Worksheet

•

4th Grade - University

Ninjago

72 questions

Ninjago

quiz

Worksheet

•

KG - Professional Dev...

WCA Welcome to the Industry Quizziz 2

73 questions

WCA Welcome to the Industry Quizziz 2

quiz

Worksheet

•

9th Grade - University

Surgery

72 questions

Surgery

quiz

Worksheet

•

12th Grade - University