Tuyển tập báo cáo các nghiên cứu khoa học quốc tế ngành hóa học dành cho các bạn yêu hóa học tham khảo đề tài: Research Article Dynamic Resource Assignment and Cooperative Relaying in Cellular Networks: Concept and Performance Assessment | Hindawi Publishing Corporation EURASIP Journal on Wireless Communications and Networking Volume 2009 Article ID 475281 14 pages doi 2009 475281 Research Article Dynamic Resource Assignment and Cooperative Relaying in Cellular Networks Concept and Performance Assessment Klaus Doppler 1 Simone Redana 2 Michal Wodczak 3 Peter Rost 4 and Risto Wichman5 1 Radio Communication CTC Nokia Research Center Itamerenkatu 11-13 00180 Helsinki Finland 2Radio Systems Research Technology Research Technology and Platforms Nokia Siemens Networks GmbH Co. KG St. Martin Strasse 76 81541 Munich Germany 3Applied Research Telcordia Technologies Telcordia Poland Sp. . ul. Umultowska 85 61-614 Poznan Poland 4 Vodafone Chair Mobile Communications Systems Technical University of Denmark Helmholtzstr. 10 01069 Dresden Germany 5 Department of Signal Processing and Acoustics Helsinki University of Technology . Box 3000 02015 TKK Finland Correspondence should be addressed to Klaus Doppler Received 18 February 2009 Revised 19 May 2009 Accepted 1 July 2009 Recommended by Mischa Dohler Relays are a cost-efficient way to extend or distribute high data rate coverage more evenly in next generation cellular networks. This paper introduces a radio resource management solution based on dynamic and flexible resource assignment and cooperative relaying as key technologies to enhance the downlink performance of relay-based OFDMA cellular networks. It is illustrated how the dynamic resource assignment is combined with beamforming in a macrocellular deployment and with soft-frequency reuse in a metropolitan area deployment. The cooperative relaying solution allows multiple radio access points to cooperatively serve mobile stations by combining their antennas and using the multiantenna techniques available in the system. The proposed schemes are compared to BS only deployments in test scenarios which have been defined in the WINNER project to be representative for next .
