Introduction to MATLAB and discussion of most important commands, simulation of a simple transmission chain, channel coding (convolutional codes), coding gain, channels with multipath propagation, models of fading channels and performance for binary transmission, Orthogonal Frequency-Division Multiplexing (OFDM), interleaving, implementation of an OFDM modem.



Deterministic and stochastic representation of mobile radio channels; time-variant linear systems; probability density functions of fading channels; noise and interference; diversity; multichannel transmission and linear combining techniques; spread spectrum and code-division multiple access (CDMA) systems; hypothesis testing and minimal error probability; sufficient statistics; conventional detection; near-far problem; joint detection; detection in asynchronous CDMA systems; synchronization with phase-locked loops (PLLs) and delay-locked loops (DLLs); demodulation in UMTS with wideband CDMA (uplink and downlink); overview UMTS.

 


  1.  Introduction to Digital Communications (Lab)
  2.  Introduction to Information Theory and Coding (Lab)
  3. Digital Communication Over Fading Channels (Lab)


The introductory meeting is on Monday 12.11.18 at 13.00 (ComLab).

First, we have a short sequence of lectures giving an overview over existing wireless communication systems, the characterization of wireless channels and signal processing in transceivers for wireless communications on a fundamental level. Then, the general system set-up including transmitter signal processing, the channel description and receiver schemes with/without coding will be instantiated for different types of today’s wireless systems. In view of the plethora of systems ranging from radio frequency identification (RFID), short-range radio and cellular systems to satellite communications and outdoor and indoor wireless positioning systems, we will focus on specific examples. The latter include analog wireless broadcasting, wireless personal area networks (WPANs), wireless local area networks (WLANs), third generation (3G) cellular mobile radio, fourth generation (4G), fifth generation (5G), concepts for systems beyond 5G, Massive MIMO, adaptive beamforming, cooperative communication, cognitive radio and filter banks. Furthermore, it is foreseen to give a brief overview over usual design tools, standardization bodies and research activities relevant to signal processing in wireless communication systems.


OSI model, introduction to tasks in the DLC and MAC layer; treatment of the PHY layer; description of communication systems for different transmission mediums: wired, wireless, mobile, and fiber-optical transmission; impact of different system components and other factors to the possible transmission quality (e.g., capacity, bit-error rate).

Overview of spread spectrum based transmission (direct sequence, frequency hopping), PN sequences, transmission over fading multipath channels, channel coding for multipath channels, multiple-input multiple-output (MIMO) transmission, multiuser detection, code-division multiple access (CDMA) and random access.

Fundamentals in information theory, entropy, mutual information; typical sequences and Shannon capacity for the discrete memoryless channel; channel coding: block codes, cyclic block codes, systematic form; soft and hard decision and performance; interleaving and code con-catenation; convolutional codes: tree and state diagrams, transfer function, distance properties; the Viterbi algorithm; source coding: fixed-length and variable-length codes, Huffman coding; the Lempel-Ziv algorithm; coding for analog sources, rate-distortion function; pulse-code modulation; delta-modulation, model-based source coding, linear predictive coding (LPC).

Fundamentals in probability Theory, Fourier transform, stochastic processes, sampling theorem (sampling and reconstruction), digital modulation techniques, communication signals and systems, characterization of thermal noise, signal space, signal detection and optimum receivers for the AWGN channel.

Die Veranstaltung dient der Vorbereitung zu den Wiederholungsprüfungen im Modul "Signalübertragung".