tailieunhanh - Báo cáo hóa học: " Research Article Turbo Decision Aided Receivers for Clipping Noise Mitigation in Coded OFDM"

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 Turbo Decision Aided Receivers for Clipping Noise Mitigation in Coded OFDM | Hindawi Publishing Corporation EURASIP Journal on Wireless Communications and Networking Volume 2008 Article ID 352597 10 pages doi 2008 352597 Research Article Turbo Decision Aided Receivers for Clipping Noise Mitigation in Coded OFDM Maxime Colas 1 Guillaume Gelle 1 and David Declercq2 1 Decom-Crestic Lab University of Reims Champagne-Ardenne BP 1039 51687 Reims Cedex2 France 2 ETIS Lab Ecole Nationale Superieure de l Electronique et de ses Applications 6 Avenue du Ponceau 95014 Cergy Pontoise Cedex France Correspondence should be addressed to Guillaume Gelle Received 11 July 2006 Revised 26 January 2007 Accepted 31 August 2007 Recommended by Luc Vandendorpe Orthogonal frequency division multiplexing OFDM is the modulation technique used in most of the high-rate communication standards. However OFDM signals exhibit high peak average to power ratio PAPR that makes them particularly sensitive to nonlinear distortions caused by high-power amplifiers. Hence the amplifier needs to operate at large output backoff thereby decreasing the average efficiency of the transmitter. One way to reduce PAPR consists in clipping the amplitude of the OFDM signal introducing an additional noise that degrades the overall system performance. In that case the receiver needs to set up an algorithm that compensates this clipping noise. In this paper we propose three new iterative receivers with growing complexity and performance that operate at severe clipping the first and simplest receiver uses a Viterbi algorithm as channel decoder whereas the other two implement a soft-input soft-output SISO decoder. Each soft receiver is analyzed through EXIT charts for different mappings. Finally the performances of the receivers are simulated on both short time-varying channel and AWGN channel. Copyright 2008 Maxime Colas et al. This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use distribution