22-Elec-B3 Digital Communications Systems: December 2019

Paper format. National Examinations — December 2019, 16-Elec-B3 Digital Communication Systems. Three hours, closed book; an approved Casio or Sharp calculator is permitted. Five questions of 25 marks each are printed; any four constitute a complete paper worth 100 marks, and only the first four appearing in the answer book are marked. All five questions are solved here, because this set is a study resource rather than a marked script. Note 1 of the cover page invites the candidate to submit a clear statement of any assumption made where a question is open to interpretation — that licence is used explicitly in Question 3(a).

Reference texts.

• S. Haykin, Communication Systems, 5th ed. — matched filtering and optimum detection, noise power spectral density, sampling and quantisation.
• B. P. Lathi and Z. Ding, Modern Digital and Analog Communication Systems, 4th ed. — PCM, aliasing, spread spectrum, link power budgets.
• B. Sklar, Digital Communications: Fundamentals and Applications, 2nd ed. — convolutional coding and the Viterbi algorithm, communications link analysis, spread-spectrum techniques.
• J. G. Proakis and M. Salehi, Digital Communications, 5th ed. — correlation receivers, error probability in AWGN, trellis decoding.