Linear Block Codes

Question 1

A linear code

a. Sum of code words is also a code word
b. All-zero code word is a code word
c. Minimum hamming distance between two code words is equal to weight of any non zero code word
d. All of the above

Answer 1

All of the above

Question 2

The process of coding multiplexer output into electrical pulses or waveforms for transmission is called

a. Line coding
b. Amplitude modulation
c. FSK
d. Filtering

Answer 2

Line coding

Question 3

For a line code, the transmission bandwidth must be

a. Maximum possible
b. As small as possible
c. Depends on the signal
d. None of the above

Answer 3

As small as possible

Question 4

Parity bit coding may not be used for

a. Error in more than single bit
b. Which bit is in error
c. Both a & b
d. None of the above

Answer 4

Both a & b

Question 5

Parity check bit coding is used for

a. Error correction
b. Error detection
c. Error correction and detection
d. None of the above

Answer 5

Error detection

Question 6

For hamming distance dmin and t errors in the received word, the condition to be able to correct the errors is

a. 2t + 1 ≤ dmin
b. 2t + 2 ≤ dmin
c. 2t + 1 ≤ 2dmin
d. Both a and b

Answer 6

Both a and b

Question 7

For hamming distance dmin and number of errors D, the condition for receiving invalid codeword is

a. D ≤ dmin + 1
b. D ≤ dmin – 1
c. D ≤ 1 – dmin
d. D ≤ dmin

Answer 7

D ≤ dmin – 1

Question 8

The process of coding multiplexer output into electrical pulses or waveforms for transmission is called

a. Line coding
b. Amplitude modulation
c. FSK
d. Filtering

Answer 8

Line Coding

Question 9

For a line code, the transmission bandwidth must be

a. Maximum possible
b. As small as possible
c. Depends on the signal
d. None of the above

Answer 9

As small as possible

Question 10

Graphical representation of linear block code is known as

a. Pi graph
b. Matrix
c. Tanner graph
d. None of the above

Answer 10

Tanner graph