Codierte Modulation in modernen Übertragungssystemen

Modern communication systems offer high speed and reliable data transmission services. The quality of these services is achieved by combining coded multi-level modulation techniques and modern digital signal processing (Viterbi-decoding) in the receiver. In this paper we first present an introduction to Trellis Coded Modulation (TCM) and then some new results on unversal techniques adapted for the AWGN-channel as well as for the fading channel. It is shown that TCM is well suited for communication channels with time variant characteristics (e.g. mobile communication channels), especially when our new codes are applied.     

Deregulierung und Sicherheit in der Energieversorgung

Ohne Zusammenfassung     

Prinzipien der Powerline Communication

The liberalization of the electricity and telecommunications markets has paved the way for harnessing existing electricity supply networks to transfer data from the low-voltage transformer station right through to every mains socket in a building. Powerline communication (PLC) allows for coupling power supply with data transmission. The modulation or demodulation calls for state-of-the-art, fast chip technologies as well as algorithms. According to powerline companies, the first generation of products is to be launched in the year 2001. Further development of this system depends completely on the regulation of the respective frequency levels. If regulatory measures and the market were to favor powerline technology, electric utility companies could come to play a role as telecom providers.     

Soft eigenvalue assignment with limited disturbance feedforward and state controller norm

The method of softly assigning eigenvalues is attractive for design problems where constraining the control effort and disturbance feedforward is more important than following the exact pole location.     

Finite-Elemente-Analyse einer Transversalflussmaschine

An efficient and resource saving method to generate the different angular rotor positions of a transverse flux machine with a 3D finite element model is presented. The calculations are performed with the superelement analysis of the EMAS solver. From the magnetostatic results the torque-position relationships and the stray field energy in the rotor shaft are evaluated in the steady state condition for different values of the excitation current.     

Advances in Digital Front-End and Software RF Processing： Part II

In the first editorial of this two-part special issue, we pointed out that one of the biggest trends in wireless broadband, radar, sonar, and broadcasting technology is software RF processing and digital front-end [1]. This     

Neue Potenziale durch die automatisierte Unternehmenskommunikation

An automated enterprise communication enables enterprise spanning integration of costumers, suppliers, logistics service provider and other enterprises by exchanging data and providing services. This communication is now, by the standardization of web services, economical and reachable. After an explanation of web services as the technological enabler two examples of use of enterprise communication are presented. The first is enterprise spanning product configuration. The second considers virtual enterprises. A critical view of questions that are still open as well as an outlook close this article.