tailieunhanh - Báo cáo hóa học: "Research Article Multiresolution with Hierarchical Modulations for Long Term Evolution of UMTS"

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 Multiresolution with Hierarchical Modulations for Long Term Evolution of UMTS | Hindawi Publishing Corporation EURASIP Journal on Wireless Communications and Networking Volume 2009 Article ID 240140 11 pages doi 2009 240140 Research Article Multiresolution with Hierarchical Modulations for Long Term Evolution of UMTS Americo Correia 1 2 Nuno Souto 1 2 Armando Soares 2 Rui Dinis 1 and Joao Silva1 2 1Instituto de Telecomunicacoes IT Av. Rovisco Pais 1 Lisboa 1049-001 Portugal 2Instituto Superior de Ciencias do Trabalho e da Empresa ISCTE Av. das Forcas Armadas Lisboa 1649-026 Portugal Correspondence should be addressed to Americo Correia Received 30 July 2008 Revised 10 December 2008 Accepted 26 February 2009 Recommended by Lingyang Song In the Long Term Evolution LTE of UMTS the Interactive Mobile TV scenario is expected to be a popular service. By using multiresolution with hierarchical modulations this service is expected to be broadcasted to larger groups achieving significant reduction in power transmission or increasing the average throughput. Interactivity in the uplink direction will not be affected by multiresolution in the downlink channels since it will be supported by dedicated uplink channels. The presence of interactivity will allow for a certain amount of link quality feedback for groups or individuals. As a result an optimization of the achieved throughput will be possible. In this paper system level simulations of multi-cellular networks considering broadcast multicast transmissions using the OFDM OFDMA based LTE technology are presented to evaluate the capacity in terms of number of TV channels with given bit rates or total spectral efficiency and coverage. multiresolution with hierarchical modulations is presented to evaluate the achievable throughput gain compared to single resolution systems of Multimedia Broadcast Multicast Service MBMS standardised in Release 6. Copyright 2009 Americo Correia et al. This is an open access article distributed under the Creative Commons Attribution License .