Questão 1
Questão
... is a measure of uncertainty
Responda
-
Encoding
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Entropy
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Information
-
Redundancy
Questão 2
Questão
{1,2,3,4,5,6} is the sample space of ...
Questão 3
Questão
A redundancy of a code S = ...
Responda
-
1 - Iavr/Imax
-
Iavr/Imax
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1 + Iavr/Imax
-
Imax/Iavr
Questão 4
Questão
An average length of codewords qavr = ...
Responda
-
∑ (pi * qi)
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∑ (pi / qi)
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∑ pi
-
∑ qi
Questão 5
Questão
An efficiency of a code E = ...
Responda
-
Iavr/Imax
-
Imax/Iavr
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Iavr/100
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Imax - Iavr
Questão 6
Responda
-
Variable length code
-
Fixed length code
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Error-correction code
-
None of the given
Questão 7
Questão
By the Bayes' rule for conditional entropy H(Y|X) \= ...
Responda
-
H(X|Y) - H(X) + H(Y)
-
[P(B|A)][P(A)] /P(B)
-
H(X|Y) - H(X)
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H(X|Y)+ H(Y)
Questão 8
Questão
By the Bayes' theorem ...
Questão 9
Questão
21. By the Chain rule H(X,Y) \= H(Y|X) + ...
Questão 10
Questão
By the Hartley's formula the amount of information I = ...
Responda
-
I = n*log m
-
I = m*n
-
I = log (m/n)
-
I = log (m*n)
Questão 11
Questão
By the Hartley's formula the entropy H = ...
Responda
-
H \= - ∑(pi * log pi)
-
H \= - ∑ (log pi)
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H \= log m
-
H \= - ∑ (pi / log pi)
Questão 12
Questão
By the property of joint entropy H(X,Y) <= ...
Responda
-
H(X)
-
H(Y)
-
H(X) + H(Y)
-
None of the given
Questão 13
Questão
By the property of joint entropy H(X,Y) ...
Responda
-
H(X,Y) >= H(X) and H(X,Y) <= H(Y)
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H(X,Y) <= H(X) and H(X,Y) >= H(Y)
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H(X,Y) >= H(X) and H(X,Y) >= H(Y)
-
H(X,Y) >= H(X) + H(Y)
Questão 14
Questão
By the Shannon's formula the amount of information I = ...
Questão 15
Questão
By the Shannon's formula the entropy H = ...
Responda
-
H \= - ∑( pi * log pi)
-
H \= - ∑ (log pi)
-
H \= - ∑ pi
-
H \= - ∑ (pi / log pi)
Questão 16
Questão
Calculate the code rate for Hamming (15,11) code
Questão 17
Questão
Calculate the code rate for Hamming (31,26) code
Questão 18
Questão
Choose the formula to determine the number N of possible messages with length n if the message source alphabet consists of m characters, each of which can be an element of the message
Responda
-
N = mn
-
N = nm
-
N = m*n
-
N = log m
Questão 19
Questão
Code is optimal when ...
Responda
-
qavr = H
-
qavr ≠H
-
qavr <H
-
qavr >H
Questão 20
Questão
Code rate R (k information bits and n total bits) is defined as
Responda
-
k = n/R
-
R = k * n
-
n = R * k
-
R = k/n
Questão 21
Questão
Conditional entropy H(Y|X) lies between
Responda
-
- H(Y) and 0
-
0 and H(Y)
-
- H(Y) and H(Y)
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0 and 1
Questão 22
Questão
Conditional probability P(B|A) = ...
Responda
-
P(A and B)/P(A)
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[P(B|A)][P(A)] /P(B)
-
P(A and B)*P(A)
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[P(B|A)][P(A)] * P(B)
Questão 23
Questão
Find the information amount of a symbol from the language with total number of symbols n = 18.
Responda
-
I = log218
-
I = log182
-
I = 18 * log218
-
I = 18 * log182
Questão 24
Questão
For a Hamming (15, 11) code, 15 is the total number of bits and 11 is the number of ...
Responda
-
redundant bits
-
data bits
-
parity bits
-
none of the given
Questão 25
Questão
Which of the following symbols will get the shortest codeword after Shannon-Fano coding if probabilities are p(a) = 0.05, p(b) = 0.6, p(c) = 0.2 and p(d) = 0.15?
Questão 26
Questão
Which of the following is not a correct statement about a probability.
Responda
-
It must have a value between 0 and 1
-
It is the collection of several experiments
-
A value near 0 means that the event is not likely to occur/happens
-
It can be reported as a decimal or a fraction
Questão 27
Questão
Which of the following is a part the channel coding?
Responda
-
Huffman code
-
Hamming code
-
Shannon-Fano code
-
RLE code
Questão 28
Questão
For a Hamming (31, 26) code, 31 is the total number of bits and 26 is the number of ...
Responda
-
redundant bits
-
data bits
-
parity bits
-
none of the given
Questão 29
Questão
For Hamming distance d<sub>min</sub> and s errors in the received word, the condition to be able to correct the errors is
Responda
-
dmin>= s+1
-
dmin>= 2s+1
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dmin>= 2s+2
-
dmin>= s+2
Questão 30
Questão
Hamming distance can easily be found with ...
Responda
-
XNOR operation
-
XOR operation
-
OR operation
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AND operation
Questão 31
Questão
In a throw of coin what is the probability of getting head.
Questão 32
Questão
Specify the formula to calculate numbers of k and n bits to create the Hamming code
Responda
-
(n, k) = (2r - 1, 2r - 1 - r)
-
(n, k) = (2r, 2r - 1 - r)
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(n, k) = (2r - 1, 2r - r)
-
(n, k) = (2r - 1, 2r - 1 + r)
Questão 33
Questão
In a throw of coin what is the probability of getting tails.
Questão 34
Questão
Specify the formula to find the amount of information if events have different probabilities.
Responda
-
Hartley's formula
-
Shannon's formula
-
Fano's formula
-
Bayes' formula
Questão 35
Questão
Specify the formula to find the amount of information if events have the same probabilities.
Responda
-
Shannon's formula
-
Hartley's formula
-
Fano's formula
-
Bayes' formula
Questão 36
Questão
Specify the most effective type of code when an alphabet consists of 2 symbols with probabilities p(x1) = 0,05 and p(x2) = 0,95.
Questão 37
Questão
In digital communication system, smaller the code rate, ... are the redundant bits.
Responda
-
a. less
-
b. equal
-
c. more
-
d. unpredictable
Questão 38
Questão
Specify the right formula if dmin is Hamming distance, s - number of correctable errors and r - number of detectable errors.
Responda
-
dmin>= s+r+1
-
dmin>= 2s+r+1
-
dmin>= s+2r+1
-
dmin>= s+r+2
Questão 39
Questão
Specify two types of error control algorithms
Responda
-
block and linear
-
linear and nonlinear
-
block and convolution
-
none of the given
Questão 40
Questão
Noise affects ...
Responda
-
information source
-
receiver
-
channel
-
transmitter
Questão 41
Questão
The basic idea behind Shannon-Fano coding is to
Responda
-
compress data by using more bits to encode more frequently occuring characters
-
compress data by using fewer bits to encode more frequently occuring characters
-
compress data by using fewer bits to encode fewer frequently occuring characters
-
expand data by using fewer bits to encode more frequently occuring characters
Questão 42
Questão
Probability of occurrence of an event lies between
Responda
-
-1 and 0
-
0 and 1
-
-1 and 1
-
exactly 1
Questão 43
Questão
The Hamming distance between "client" and "server" is
Responda
-
0
-
1
-
6
-
impossible to detect
Questão 44
Questão
The Hamming distance between "make" and "made" is
Responda
-
4
-
3
-
1
-
impossible to detect
Questão 45
Questão
The Hamming distance between "push" and "pull" is
Responda
-
0
-
4
-
2
-
impossible to detect
Questão 46
Questão
Probability of second event in situation if first event has been occurred is classified as
Responda
-
conditional probability
-
joint entropy
-
conditional entropy
-
none of the given
Questão 47
Questão
The Hamming distance between "starting" and "finishing" is
Responda
-
4
-
3
-
impossible to detect
-
5
Questão 48
Questão
The Hamming distance between 001111 and 010011 is
Questão 49
Questão
Shannon-Fano and Huffman codes are an encoding algorithms used for
Questão 50
Questão
The Hamming distance between 010111 and 010011 is
Questão 51
Questão
The Hamming distance between 011111 and 010011 is
Questão 52
Questão
Specify parts of the receiver side
Responda
-
Source encoder, channel encoder, digital modulator
-
Source decoder, channel decoder, digital demodulator
-
Source decoder, channel encoder, digital modulator
-
Source encoder, channel decoder, digital modulator
Questão 53
Questão
The Hamming distance between 101001 and 010011 is
Questão 54
Questão
The Hamming distance between two strings with equal length is ...
Responda
-
the number of positions at which the corresponding symbols are different
-
the number of positions at which the corresponding symbols are equal
-
the number of identical symbols in the first string
-
the number of identical symbols in the second string
Questão 55
Questão
Specify parts of the transmitter side
Responda
-
Source decoder, channel decoder, digital demodulator
-
Source encoder, channel encoder, digital modulator
-
Source decoder, channel encoder, digital modulator
-
Source encoder, channel decoder, digital modulator
Questão 56
Questão
The number of digits by which any two binary sequences differ is called the ...
Responda
-
Hamming weight
-
Hamming distance
-
Hamming code
-
Hamming length
Questão 57
Questão
Specify the case when entropy is maximum
Responda
-
p1=0,5 and p2=0,5
-
p1=1 and p2=0
-
p1=0 and p2=1
-
p1=0,9 and p2=0,1
Questão 58
Questão
The prefix code is also known as ...
Responda
-
block code
-
uniquely decodable code
-
convolutional code
-
parity bit
Questão 59
Questão
In a throw of dice what is the probability of getting number greater than 5.
Responda
-
a. 1/3
-
b. 1/6
-
c. 1/5
-
d. 1
Questão 60
Questão
The string was encoded with Hamming (15,11) code using the transformation matrix. Specify numbers of positions of the parity bits.
Responda
-
12,13,14,15
-
1,2,3,4
-
1,2,4,8
-
2,3,4,5
Questão 61
Questão
78. For a Hamming (31, 26) code, 31 is the total number of bits and 26 is the number of ...
Responda
-
a. redundant bits
-
b. data bits
-
c. parity bits
-
d. none of the given
Questão 62
Questão
The string was encoded with Hamming (31,26) code using the transformation matrix. Specify numbers of positions of the parity bits.
Responda
-
27,28,29,30,31
-
1,2,3,4,5
-
1,2,4,8,16
-
2,3,4,5,6
Questão 63
Questão
79. For a Hamming (7, 4) code, 7 is the total number of bits and 4 is the number of ...
Responda
-
a. redundant bits
-
b. data bits
-
c. parity bits
-
d. none of the given
Questão 64
Questão
When data is compressed, the goal is to reduce
Responda
-
noise
-
redundancy
-
channel capacity
-
none of the given
Questão 65
Questão
When the base of the logarithm is 10, then the unit of measure of information is
Questão 66
Questão
43. Code has dmin = 3. How many errors can be detected by this code?
Questão 67
Questão
When the base of the logarithm is 2, then the unit of measure of information is
Questão 68
Questão
When the base of the logarithm is e, then the unit of measure of information is
Questão 69
Questão
Which block or device does the data compression?
Responda
-
Channel encoder
-
Source encoder
-
Modulator
-
None of the given
Questão 70
Questão
Which letter will get the shortest codeword after Huffman coding of the word "abracadabra"?
Questão 71
Questão
Which of the following codes has the highest code rate?
Questão 72
Questão
Which of the following codes has the highest redundancy?
Questão 73
Questão
Which of the following codes is non-uniform?
Responda
-
Shannon-Fano
-
ASCII
-
Hamming
-
None of the given
Questão 74
Questão
Which of the following codes is prefix?
Responda
-
0, 111, 11
-
0, 111, 10
-
0, 101, 10
-
00, 10, 101
Questão 75
Questão
Which of the following codes is prefix?
Responda
-
0, 01, 11
-
0, 10, 11
-
0, 10, 1
-
0, 01, 001
Questão 76
Questão
Which of the following codes is uniform?
Responda
-
ASCII
-
Shannon-Fano
-
Huffman
-
None of the given
Questão 77
Questão
Which of the following codes is uniform?
Responda
-
10,011,11,001,010
-
0,10,110,1110,1111
-
10,01,0001,100,1010
-
100,110,001,000,010
Questão 78
Questão
Which of the following indicate(s) an error in a received combination?
Responda
-
Parity bits
-
Error syndrome
-
Data bits
-
None of the given
Questão 79
Questão
The string was encoded with Hamming (7,4) code using the transformation matrix. Specify numbers of positions of the parity bits.
Responda
-
a. 5,6,7
-
a. 1,2,3
-
a. 1,2,4
-
a. 2,3,4