Helsinki University of Technology

Helsinki University of Technology
Communications Laboratory
Timo O. Korhonen

S-72.227 Digital Communication Systems
Study Guide 3: The Viterbi algorithm, coherent bandpass modulation

Topics

Viterbi algorithm

Carrier wave (CW) binary waveforms

Optimum binary and coherent modulators

FSK and PSK spectral densities

General

Example of using Viterbi algorithm, survivor path

What is the difference between soft and hard decoding?

What are the two basic ways to realize optimum detection?

Discuss a derivation for FSK and/or PSK spectral density

Compare various modulation methods with respect of their spectral efficiencies

References

Bruce Carlson: Communication Systems III Ed, pp. 501-532

B.P. Lathi: Modern Digital and Analog Communication Systems III Ed, pp. 747-758, 577-594

J.G. Proakis: Digital Communications III Ed, pp. 470-511

http://pw1.netcom.com/~chip.f/Viterbi.html

DAG Instructions

This guide is intended for Discussion Agent Group (DAG) members, but in can be used also by other students. DAG members should get themselves familiar with the lecture material and Study Guide well before the lecture and make clear for themselves the themes they would like to generate discussion. If it appears that there remains unsolved questions after the session they will be discussed in next sessions. It is important to note the time reserved for discussion is maximum of 45 min. only.

Group's tasks

Group should select session Chair. The role of the session chair is to give the floor for audience and to guide discussion generally.

Group should select a secretary whose task is to write down all the questions and answers popping out at the session. The minutes should be submitted to the course instructor within two days and it will appear at the course homepage.

Lecture themes (from lecture transparencies and study guides) must be divided to group members such that each member shall carry about the same workload. Also chair and secretary must participate on drafting the questions.

Member's tasks

Each group member should

Make a list of interesting questions/issues she/he knows the answer. Purpose of these questions is to clarify/underline important topics of the lecture (from one's personal view)
Make a list of topics/themes/details that are not understood
Propose answers to the suggested questions (as listed above)
Ask the suggested questions from the audience during the session