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: Space-Time Joint Interference Cancellation Using Fuzzy-Inference-Based Adaptive Filtering Techniques in Frequency-Selective Multipath Channels | Hindawi Publishing Corporation EURASIP Journal on Applied Signal Processing Volume 2006 Article ID 62052 Pages 1-17 DOI ASP 2006 62052 Space-Time Joint Interference Cancellation Using Fuzzy-Inference-Based Adaptive Filtering Techniques in Frequency-Selective Multipath Channels Chia-Chang Hu 1 Hsuan-Yu Lin 1 Yu-Fan Chen 2 and Jyh-Horng Wen1 3 1 Department of Electrical Engineering National Chung Cheng University Min-Hsiung Chia-Yi 621 Taiwan 2 Department of Communications Engineering National Chung Cheng University Min-Hsiung Chia-Yi 621 Taiwan 3 Institute of Communication Engineering National Chi Nan University Puli Nantou 545 Taiwan Received 7 March 2005 Revised 29 May 2005 Accepted 19 July 2005 Recommended for Publication by Helmut Bolcskei An adaptive minimum mean-square error MMSE array receiver based on the fuzzy-logic recursive least-squares RLS algorithm is developed for asynchronous DS-CDMA interference suppression in the presence of frequency-selective multipath fading. This receiver employs a fuzzy-logic control mechanism to perform the nonlinear mapping of the squared error and squared error variation denoted by e2 Ae2 into a forgetting factor Ẳ. For the real-time applicability a computationally efficient version of the proposed receiver is derived based on the least-mean-square LMS algorithm using the fuzzy-inference-controlled step-size M. This receiver is capable of providing both fast convergence tracking capability as well as small steady-state misadjustment as compared with conventional LMS- and RLS-based MMSE DS-CDMA receivers. Simulations show that the fuzzy-logic LMS and RLS algorithms outperform respectively other variable step-size LMS VSS-LMS and variable forgetting factor RLS VFF-RLS algorithms at least 3 dB and dB in bit-error-rate BER for multipath fading channels. Copyright 2006 Hindawi Publishing Corporation. All rights reserved. 1. INTRODUCTION Direct-sequence code-division multiple access DS-CDMA a specific form of .
