Question 1 was marked out of 4:

marks were awarded as follows:

- 1 for figuring out the symbol rate for no-ISI
- 1 for computing the bit rate (relative to answer above)
- 1 for computing required SNR, 1 for computing the corresponding noise power

Question 2 was marked out of 4:

marks were awarded as follows:

- 1 for looking up the right bit values and using them in the correct order
- 1 for correctly doing the Manchester encoding and drawing the waveform
- 1 for correctly calculating the min/max time durations
- 1 for correctly computing the bit rate

Question 3 marked out of 5

marks were awarded as follows:

- 1 for the right generator polynomial in bits
- 1 for deciding to divide by G(x) or for re-computing the CRC
- 2 for correct remainder or CRC calculation
- 1 for right conclusion (no error)

Question 4 marked out of 5

marks awarded as follows:

(a)  1 mark for computing the data/ack durations in bits,
     1 mark for computing the data/ack durations in ms
(b)  2 marks for throughput calculation (1 for total time, 1 for throughput)
(c)  1 mark for mentioning go-back-N and selective-repeat (1/2 mark if only one)


Question 5 marked out of  2:

- 1 mark for a correct answer to each part

Question 6 marked out of  5:

(a) 1 mark for correctly computing the number of data and parity bits
(b) 1 mark for correctly computing n and k
(c) marked as follows:
    1 mark for computing all four hamming distances (not just one)
    1 mark for choosing the correct codeword
    1 mark for the number of errors corrected

Question 7 marked out of 5:

marks as follows:

- 1 per correct answer, 0.5 if answer partially correct