Wireless and Mobile Communications Multiple choice Questions and Answers-Equalization,Diversity and Channel Coding

61.	How many redundant bits are added in block codes for k information bits and n code bits?
a.	n+k
b.	n-k
c.	k²
d.	n²

Discuss

Answer: (b).n-k

62.	For (n,k) block codes, rate of the code is defined as __________
a.	n²/k
b.	k²/n
c.	n/k
d.	k/n

Discuss

Answer: (c).n/k

63.	The ability of the block code to correct errors is a function of __________
a.	Number of parity bits
b.	Number of information bits
c.	Number of code bits
d.	Code distance

Discuss

Answer: (d).Code distance

64.	The weight of code is given by number of _______
a.	Non-zero elements in the codeword
b.	Zero elements in the codeword
c.	Total elements in the codeword
d.	Elements in parity bits

Discuss

Answer: (a).Non-zero elements in the codeword

65.	Which of the following is not a property of block code?
a.	Linearity
b.	Systematic
c.	Cyclic
d.	Non linearity

Discuss

Answer: (d).Non linearity

66.	In systematic codes, parity bits are appended at the __________
a.	Beginning
b.	End
c.	End
d.	Odd places

Discuss

Answer: (c).End

67.	Which of the following is not an example of block code?
a.	Hamming code
b.	Cyclic code
c.	Convolution code
d.	BCH codes

Discuss

Answer: (c).Convolution code

68.	Which of the following code is a class of non-binary BCH?
a.	Hamming code
b.	Hadamard code
c.	Golay code
d.	Reed Solomon codes

Discuss

Answer: (d).Reed Solomon codes

69.	Which of the following linear codes achieve largest possible minimum distance?
a.	Hamming code
b.	Hadamard code
c.	Golay code
d.	Reed Solomon codes

Discuss

Answer: (d).Reed Solomon codes

70.	CDPD stands for ___________
a.	Cellular Digital Packet Data
b.	Cellular Decoded Packet Data
c.	Cellular Demodulated Packet Data
d.	Cellular Decoded Plane Data

Discuss

Answer: (a).Cellular Digital Packet Data