Syllabus academic year 2009/2010
(Created 2009-08-11.)
DIGITAL COMMUNICATIONSETT051

Higher education credits: 7,5. Grading scale: TH. Level: G2 (First level). Language of instruction: The course might be given in English. Compulsory for: C3, MWIR1. Alternative for: MFOT1. Optional for: D4, D4ks, D4sst, E4, E4ks, F4, Pi4, Pi4sbs. Course coordinator: Göran Lindell, Goran.Lindell@it.lth.se, Inst för elektro- och informationsteknik. Assessment: Written examination (5 h) normally consists of five problems. Approved labs is a requirement to be allowed to enter the examination. Home page: http://www.eit.lth.se/course/ett051.

Aim
The aim of this course is to give basic knowledge of principles, concepts, functioning, performance and limitations of digital communication systems.

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

Contents
Introduction: An overview is given of a general communication link consisting of the three parts transmitter – communication channel – receiver. Examples of digital communication methods are introduced for realistic bit rates and noise levels.

The transmitter: The principles, structure and functioning of the transmitter are explained. Basic binary and M-ary digital communication methods are presented such as: phase shift keying (PSK), quadrature amplitude modulation (QAM), frequency shift keying (FSK) and orthogonal frequency division multiplex (OFDM). Communication methods that use several transmitter and receiver antennas (MIMO system) are briefly discussed. The efficiency with respect to bit rate, bandwidth and signal power is evaluated for different methods. Multiple access techniques are briefly discussed in connection with multi-user communication systems.

The communication channel: The influence of the communication channel on the transmitted information carrying signals is investigated. The consequences of multi-path propagation and noise on the bit rate is also studied. Disturbing signals, noise and other unwanted signals are described and modelled (typically as additive white Gaussian noise in this course). The influence of different transmission media such as air, metallic conductors and optical fibers are briefly discussed.

The receiver: The principles (MAP and ML), structure and functioning of the receiver are explained. Synchronisation issues are described. The bit error probability of the receiver is analysed and calculated. The connection between bit rate, received signal power, noise level, bandwidth and error probability is clarified. The concept of diversity is briefly discussed and illustrated. Technical challenges when using very high bit rates, such as the presence of inter-symbol interference (ISI), is described.

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

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