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19. Unit wise Bits
CHOOSE THE CORRECT ANSWER
1. A source is transmitting six messages with
probabilities,1/2,1/4,1/8,1/16,1/32,and1/32.Then
(a) Source coding improves the error performance of the communication system.
(b) Channel coding will reduce the average source code word length.
(c) Two different source codeword sets can be obtained using Huffman coding.
(d) Two different source codeword sets can be obtained using Shanon-Fano coding
2.A memory less source emits 2000binarysymbols/sec and each symbol has a Probability of
0.25 to be equal to 1and 0.75 to be equal to 0.The minimum number of bits/sec required for
error free transmission of this source is
(a) 1500
(b) 1734
(c) 1885
(d) 162213.
3. A system has a bandwidth of 3KHz and an S/N ratio of 29dB at the input of the receiver .If
the bandwidth of
The channel gets doubled ,then
(a) its capacity gets doubled
(b) its capacity gets halved
(c) the corresponding S/N ratio gets doubled
(d) the corresponding S/N ratio gets halved
5.The capacity of a channel with infinite bandwidth is
(a) finite because of increase in noise power
(b) finite because of finite message word length
(c) infinite because of infinite noise power
(d) infinite because of infinite bandwidth