dc

a) 0 bits b) 1 bit c) 2 bits d) infinity
7) For the data word 1110 in a (7, 4) non-systematic cyclic code with the generator
polynomial 1+x 2 +x 3 , the code polynomial is [ ]
a) 1+x+x 3 +x 5 b) 1+x 2 +x 3 +x 5 c) 1+x 2 +x 3 +x 4 d) 1+x+x 5
8) A source transmitting ‘m’ number of messages is connected to a noise free channel. The
capacity of the channel is [ ]
a) m bits/symbol b) m 2 bits/symbol c) logm bits/symbol d) 2m bits/symbol
9) Which of the following is a p(Y/X) matrix for a binary symmetric channel [ ]
a) b) c) d) None
Cont…..2
Code No: 07A5EC09 :2: Set No.4
10) Exchange between channel bandwidth and (S/N) ratio can be adjusted based on [ ]
a)Shannon’s limit b)Shannon’s source coding
c) Shannon’s channel coding d) Shannon Hartley theorem
II Fill in the blanks:
11) The minimum distance of a linear block code is equal to____________________of any
non-zero code word in the code.
12) A linear block code with a minimum distance d min
can detect upto ___________________
13) For a Linear Block code Code rate =_________________
14) The information rate of a source is also referred to as entropy measured in
______________
15) H(X,Y)=______________ or __________________
16) Capacity of a noise free channel is _________________
17) The Shannon’s limit is ______________
18) The channel capacity with infinite bandwidth is not because ____________
19) Assuming 26 characters are equally likely , the average of the information content of
English language in bits/character is________________
20) The distance between two vector c1 and c2 is defined as the no.of components in which
they are differ is called as____________________
-oOo-
Code No: 07A5EC09 Set No. 1
JAWAHARLAL NEHRU TECHNOLOGICAL UNIVERSITY HYDERABAD
III B.Tech. I Sem., II Mid-Term Examinations, November – 2010
DIGITAL COMMUNICATIONS
Objective Exam
Name: ______________________________ Hall Ticket No.
Answer All Questions. All Questions Carry Equal Marks.Time: 20 Min. Marks: 20.
I Choose the correct alternative:
1) The channel matrix of a noiseless channel [ ]
a)consists of a single nonzero number in each column.
b) consists of a single nonzero number in each row.
c) is an Identity Matrix. d) is a square matrix.
2 ) Information content of a message [ ]