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 Universal Linear Precoding for NBI-Proof Widely Linear Equalization in MC Systems | Hindawi Publishing Corporation EURASIP Journal on Wireless Communications and Networking Volume 2008 Article ID 321450 13 pages doi 2008 321450 Research Article Universal Linear Precoding for NBI-Proof Widely Linear Equalization in MC Systems Donatella Darsena 1 Giacinto Gelli 2 and Francesco Verde2 1 Dipartimento per le Tecnologie Universita Parthenope Centro Direzionale I-80143 isola C4 Italy 2 Dipartimento di Ingegneria Elettronica e delle Telecomunicazioni Universita Federico II via Claudio 21 I-80125 Napoli Italy Correspondence should be addressed to Donatella Darsena darsena@ Received 1 May 2007 Accepted 1 September 2007 Recommended by Arne Svensson In multicarrier MC systems transmitter redundancy which is introduced by means of finite-impulse response FIR linear precoders allows for perfect or zero-forcing ZF equalization of FIR channels in the absence of noise . Recently it has been shown that the noncircular or improper nature of some symbol constellations offers an intrinsic source of redundancy which can be exploited to design efficient FIR widely-linear WL receiving structures for MC systems operating in the presence of narrowband interference NBI . With regard to both cyclic-prefixed and zero-padded transmission techniques it is shown in this paper that with appropriately designed precoders it is possible to synthesize in both cases WL-ZF universal equalizers which guarantee perfect symbol recovery for any FIR channel. Furthermore it is theoretically shown that the intrinsic redundancy of the improper symbol sequence also enables WL-ZF equalization based on the minimum mean output-energy criterion with improved NBI suppression capabilities. Finally results of numerical simulations are presented which assess the merits of the proposed precoding designs and validate the theoretical analysis carried out. Copyright 2008 Donatella Darsena et al. This is an open access article distributed under the Creative Commons Attribution License which
