Syllabus academic year 2009/2010
(Created 2009-08-11.)

Higher education credits: 9. Grading scale: TH. Level: A (Second level). Language of instruction: The course might be given in English. Compulsory for: MWIR1. Alternative for: MFOT1. Optional for: C4, C4ks, D4, D4ks, D4sst, E4, E4ks. Course coordinator: Göran Lindell,, Inst för elektro- och informationsteknik. Recommended prerequisits: ETT051 Digital Communications. Assessment: Written examination (5 h) normally consists of five problems. Approved lab and project is a requirement to be allowed to enter the examination. Home page:

The aim of this course is to give very good knowledge of advanced digital communication methods. The course gives a broad and deep understanding such that many of the communication methods used today, as well as many future methods, can be understood.

Knowledge and understanding
For a passing grade the student must

Skills and abilities
For a passing grade the student must

Judgement and approach
For a passing grade the student must

Introduction: Examples of advanced adaptive digital communication methods are introduced for realistic communication links.

Signal space description: A general geometric description of a communication link is given. Practical ML (and MAP) receivers are described in detail, and computer simulation models of a communication link are presented. The symbol error probability is calculated exactly for several signal constellations such as, e.g., PAM and QAM. The concept of diversity is explained and illustrated, and MIMO systems (multiple-input multiple-output) are introduced. The relationships between multi-path propagation, matched receiver filter and the so-called RAKE (receiver) structure are clarified. Alternative sub-optimum receiver structures are briefly discussed.

Combined coding and modulation: A general state-based description of coding and modulation is presented. Advantages and disadvantages of trellis-coded signals are investigated from an energy-efficiency, as well as, a bandwidth-efficiency point of view. Comparisons are made with Shannon´s capacity results. Principles of modern communication systems are studied where the transmitter adapts (bit rate, coding and modulation) depending on the quality of the communication link. Maximum likelihood sequence detection using the Viterbi algorithm is explained. The influence of the communication channel on the transmitted information carrying signals is investigated. Advantages and disadvantages of coded OFDM are clarified. The influence of different transmission media such as air, metallic conductors and optical fibers are discussed and compared. Heterodyne and homodyne receiver principles are described.

Fading channels: Mobile communication. Time-varying multi-path propagation is described. Several concepts related to fading channels are explained such as, e.g.; Doppler shift, coherens time, coherens bandwidth, multi-path spread, frequency-selective, and Rayleigh fading. Interleaving is briefly discussed. The consequences of fading on the error probability are illustrated. It is pointed out that technical solutions that are based on the concept of diversity here are very important.

Applications: Some of the following applications are considered in this course: Mobile digital telephony (3G, EDGE, GSM), WLAN, modem, ADSL, digital TV, Bluetooth, navigation (GPS), radar, surveillance systems.

Lindell, G: Introduction to Digital Communications, 2006. Compendium.