tailieunhanh - Báo cáo hóa học: " Research Article Estimation of CFO and Channels in Phase-Shift Orthogonal Pilot-Aided OFDM Systems with Transmitter Diversity"

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 Estimation of CFO and Channels in Phase-Shift Orthogonal Pilot-Aided OFDM Systems with Transmitter Diversity | Hindawi Publishing Corporation EURASIP Journal on Wireless Communications and Networking Volume 2009 Article ID 436756 10 pages doi 2009 436756 Research Article Estimation of CFO and Channels in Phase-Shift Orthogonal Pilot-Aided OFDM Systems with Transmitter Diversity Carlos Ribeiro1 and Atilio Gameiro2 1 Escola Superior de Tecnologia e Gestão Instituto Politecnico de Leiria Morro do Lena Alto Vieiro 2411-901 Leiria Portugal 2Instituto de Telecomunicacoes Universidade de Aveiro 3810-193 Aveiro Portugal Correspondence should be addressed to Carlos Ribeiro cribeiro@ Received 1 July 2008 Revised 4 November 2008 Accepted 23 January 2009 Recommended by Mounir Ghogho We present a CFO estimation algorithm and an associated channel estimation method for broadband OFDM systems with transmitter diversity. The CFO estimation algorithm explores the TD structure of the transmitted symbols carrying pilots and data relying solely on the data component present on the symbols to estimate the CFO thus avoiding additional overhead like training symbols or null subcarriers. An intermediate output of the CFO algorithm provides an easy-to-get initial CIR estimate that will be improved with the utilization of a TD LMMSE filter. The feasibility of the investigated methods is substantiated by system simulation using indoor and outdoor broadband wireless channel models. Simulation results show that the joint algorithms provide a near optimal system s performance. Copyright 2009 C. Ribeiro and A. Gameiro. This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use distribution and reproduction in any medium provided the original work is properly cited. 1. Introduction Future mobile broadband applications will require reliable high data-rate wireless communication systems. In recent years multiple-input multiple-output orthogonal frequency division multiplexing MIMO-OFDM transmission systems 1-4 emerged as .