Zur Kapazitätserhöhung in zellularen Mobilfunksystemen eignet sich der Einsatz adaptiver Antennen an der Basisstation. Diese ermöglichen die räumliche Wiederverwendung von Kanälen innerhalb einer Zelle mittels Space Division Multiple Access (SDMA). Die Kapazitätsgewinne, die mit SDMA zu erzielen sind, hängen jedoch stark von den verwendeten Verfahren des Ressourcen Managements (RM) ab. Hierzu wurden neuartige RM-Verfahren für SDMA-Systeme entwickelt, welche die räumliche Kanalwiederverwendung innerhalb der Zelle mit verschiedenen Prinzipien der interzellularen Kanalvergabe (statische und dynamische) kombinieren. Zudem wurden die entwickelten Verfahren erweitert, um auch in hierarchisch strukturierten zellularen Netzen eingesetzt werden zu können. In ausführlichen Systemsimulationen konnte gezeigt werden, dass die neuen RM-Verfahren eine Vervielfachung der Systemkapazität mit Hilfe von SDMA ermöglichen. Zusätzlich werden analytische Modelle entwickelt und ausgewertet, die den Gewinn von Verfahren vorhersagen, welche die durch die Verwendung adaptiver Antennen reduzierte Inter-Zell-Interferenz ausnutzen (Spatial Filtering for Interference Reduction-SFIR), dies wird sowohl für F/TDMA basierte Systeme als auch für CDMA Systeme analysiert.

The aim of this thesis is to introduce a non-stationary model for the scattering in mobile-to-mobile channels. Due to the evolution of wireless technology, fixed-to-mobile communications systems are nowadays complemented by mobile-to-mobile communications systems. In the vehicular sector, mobile-to-mobile communications systems are used to enable intelligent transportation systems. Such systems aim to make transportation safer and more efficient by distributing sensor information among the cars. In the aeronautical sector, mobile-to-mobile communications systems will be used, for example, to exchange position, altitude, speed, and heading data between aircraft during flight thus allowing for a reduced separation between them. Hence, these systems are necessary to further increase the air traffic density.

This book provides the proceedings of the 6th International Workshop on Multi-Carrier Spread Spectrum (MC-SS 2007), 7-9 May 2007, held in Herrsching, Germany. The book aims to edit the ensemble of the newest contributions and research results in this new field. The book presents comprehensive state-of-the-art articles about multi-carrier spread spectrum techniques, and discusses multi-carrier spread spectrum techniques.

This book constitutes the refereed proceedings of the IFIP-TC6 11th International Conference on Personal Wireless Communications, PWC 2006. The book presents 25 revised full papers and 13 revised short papers, carefully reviewed and selected from 100 submissions. The papers are organized in topical sections on mobile and wireless networking, QoS, ad-hoc, security, wireless LAN, cross-layer design, wireless sensor networks, physical layer, and mobile and wireless applications.

Tackling problems from the least complicated to the most, Resource Allocation in Uplink OFDMA Wireless Systems provides readers with a comprehensive look at resource allocation and scheduling techniques (for both single and multi-cell deployments) in uplink OFDMA wireless networks relying on convex optimization and game theory to thoroughly analyze performance. Inside, readers will find topics and discussions on: Formulating and solving the uplink ergodic sum-rate maximization problem Proposing suboptimal algorithms that achieve a close performance to the optimal case at a considerably reduced complexity and lead to fairness when the appropriate utility is used Investigating the performance and extensions of the proposed suboptimal algorithms in a distributed base station scenario Studying distributed resource allocation where users take part in the scheduling process, and considering scenarios with and without user collaboration Formulating the sum-rate maximization problem in a multi-cell scenario, and proposing efficient centralized and distributed algorithms for intercell interference mitigation Discussing the applicability of the proposed techniques to state-of-the-art wireless technologies, LTE and WiMAX, and proposing relevant extensions Along with schematics and figures featuring simulation results, Resource Allocation in Uplink OFDMA Wireless Systems is a valuable book for?wireless communications and cellular systems professionals and students.

Based on cutting-edge research projects in the field, this book (part of a comprehensive 4-volume series) provides the latest details and covers the most impactful aspects of mobile, wireless, and broadband communications development. These books present key systems and enabling technologies in a clear and accessible manner, offering you a detailed roadmap the future evolution of next generation communications. Other volumes cover Networks, Services and Applications; Reconfigurability; and Ad Hoc Networks.

Reporting the findings of COST 2100, a major European intergovernmental project, this volume offers system designers a good source of guidelines based on channel characterization and measurement-based modeling, as well as worthwhile ideas for future research.