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 Blind CP-OFDM and ZP-OFDM Parameter Estimation in Frequency Selective Channels | Hindawi Publishing Corporation EURASIP Journal on Wireless Communications and Networking Volume 2009 Article ID315765 10 pages doi 2009 315765 Research Article Blind CP-OFDM and ZP-OFDM Parameter Estimation in Frequency Selective Channels Vincent Le Nir EURASIP Member 1 Toon van Waterschoot 1 Marc Moonen EURASIP Member 1 and Jonathan Duplicy2 1ESAT SISTA Laboratory Department . Katholieke Universiteit Leuven Kasteelpark Arenberg 10 3001 Leuven-Heverlee Belgium 2Agilent Technologies Labs WingePark 51 3110 Rotselaar Belgium Correspondence should be addressed to Vincent Le Nir Received 14 November 2008 Revised 4 March 2009 Accepted 1 June 2009 Recommended by A. Lee Swindlehurst A cognitive radio system needs accurate knowledge of the radio spectrum it operates in. Blind modulation recognition techniques have been proposed to discriminate between single-carrier and multicarrier modulations and to estimate their parameters. Some powerful techniques use autocorrelation- and cyclic autocorrelation-based features of the transmitted signal applying to OFDM signals using a Cyclic Prefix time guard interval CP-OFDM . In this paper we propose a blind parameter estimation technique based on a power autocorrelation feature applying to OFDM signals using a Zero Padding time guard interval ZP-OFDM which in particular excludes the use of the autocorrelation- and cyclic autocorrelation-based techniques. The proposed technique leads to an efficient estimation of the symbol duration and zero padding duration in frequency selective channels and is insensitive to receiver phase and frequency offsets. Simulation results are given for WiMAX and WiMedia signals using realistic Stanford University Interim SUI and Ultra-Wideband UWB IEEE channel models respectively. Copyright 2009 Vincent Le Nir et al. This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use distribution and .
