English  |  正體中文  |  简体中文  |  Items with full text/Total items : 27533/39387
Visitors : 2543505      Online Users : 37
RC Version 4.0 © Powered By DSPACE, MIT. Enhanced by NTU Library IR team.
Scope Adv. Search

Please use this identifier to cite or link to this item: http://ntour.ntou.edu.tw:8080/ir/handle/987654321/11160

Title: 水下聲響感測器實作應用整合型研究(I)水下通訊系統設計與研製
Design and Implementation of Underwater Communication System
Authors: 洪賢昇;張順雄
Contributors: NTOU:Department of Electrical Engineering
Keywords: 盲蔽;等化器;符元間際干擾;多重路徑
Blind,Equalizer;Intersymbol interference;Multipath
Date: 2003-08
Issue Date: 2011-06-28T08:08:32Z
Publisher: 行政院國家科學委員會
Abstract: 在本論文中,提出了一個新的方法來設計盲蔽式適應性等化器。此方法是利用通訊訊號的週期平穩 (Cyclostationary)特性並且結合了鎖相迴路來設計盲蔽式適應性等化器。傳送訊號是經過升餘弦濾波器的脈波整形之正交相位移鍵 (QPSK)調變訊號。此等化器使用最小均方 (LMS)法則,將轉換後的橫向濾波器輸出訊號與代表頻譜線的複指數參考訊號的均方誤差最小化,並由鎖相迴路來得到參考訊號。由於所提出的等化器不需要使用訓練序列,能夠達到比傳統訓練式等化器快速的收斂速度及較佳的位元錯誤率,並且有較高的頻寬效益,能提昇通訊的容量與品質。利用電腦模擬的方式來探討此等化器在一般多重路徑所造成之符元間際干擾 (ISI)及水下通道的性能。
In this paper, we propose a novel method, that exploits the cyclostationary property of communication signals and uses the phase-locked loop, to design a blind adaptive equalizer. The Quadrature Phase Shift Keying (QPSK) modulated signal with pulse shaping obtained by the raise cosine filter is used as the transmitting signal. The proposed equalizer uses the least mean square (LMS) algorithm to minimize the mean square error between the transformed transversal filter output signal and a complex exponential signal extracted from the phase-locked loop. Because the proposed equalizer can perform equalization without using training sequences, it exhibits faster convergence speed and better bit-error rate than conventional equalizers which need usage of training sequences, thus achieving higher spectral efficiency. Therefore, the proposed equalizer can improve communication quality and increase the capacity. To evaluate the performance of the proposed equalizer, computer simulations were carried out for the cases of typical intersymbol interference (ISI) and underwater acoustic channels.
Relation: NSC92-2611-E019-015
URI: http://ntour.ntou.edu.tw/ir/handle/987654321/11160
Appears in Collections:[電機工程學系] 研究計畫

Files in This Item:

File Description SizeFormat

All items in NTOUR are protected by copyright, with all rights reserved.


著作權政策宣告: 本網站之內容為國立臺灣海洋大學所收錄之機構典藏,無償提供學術研究與公眾教育等公益性使用,請合理使用本網站之內容,以尊重著作權人之權益。
網站維護: 海大圖資處 圖書系統組
DSpace Software Copyright © 2002-2004  MIT &  Hewlett-Packard  /   Enhanced by   NTU Library IR team Copyright ©   - Feedback