自適應噪聲抵消器的設計
1.6萬字 21頁


摘要：自適應濾波技術的發(fā)展和超大規(guī)模集成電路(VLSI )技術的迅速發(fā)展與應用，從理論和技術上為通信系統(tǒng)的降噪研究提供了技術支持。在通信系統(tǒng)中，采用合適的自適應濾波技術，從被污染的信號中提取有用的信號有著廣闊的應用前景。自適應噪聲干擾抵消器是基于自適應濾波原理的一種擴展，它能從被噪聲干擾的環(huán)境中檢測和提取有用信號，抑制或衰減噪聲干擾，提高信號傳遞和接收的信噪比質量。本論文的目的在于設計一個自適應噪音抵消系統(tǒng)，使其能消除含噪語音信號中的背景噪音，達到提高語音信號質量的目的。主要工作分為兩大部分。本論文在第一部分介紹了自適應數(shù)字濾波器的基本理論思想，具體闡述了自適應噪聲抵消系統(tǒng)基本原理，并對自適應噪聲抵消系統(tǒng)的指標、抵消性能進行了計算分析。最小均方誤差(LMS )算法和遞歸最小二乘((RLS)算法進行了詳細的介紹和分析。并通過對自適應噪聲抵消器的MATLAB仿真及對仿真圖形的分析，驗證了系統(tǒng)設計和自適應算法的可行性。第二部分主要完成自適應噪聲抵消系統(tǒng)的硬件設計和軟件編程。在第一部分計算機仿真分析的基礎上，利用高速信號處理芯片DSP (TMS320LF2407)設計了一個噪聲干擾抵消系統(tǒng)，在高速信號處理芯片(TMS320LF2407)上開發(fā)實現(xiàn)了自適應LMS算法。在硬件方面，詳細介紹了利用單片機AT89S51對DSP系統(tǒng)進行在線調(diào)試的具體過程，并給出了系統(tǒng)設計的詳細電路圖。在軟件方面，給出了自適應噪聲抵消器LMS算法的軟件流程圖和相應的程序。
關鍵詞:自適應濾波，自適應噪聲干擾抵消器，LMS算法，RLS算法



Design of Adaptive Filter Based on TMS320LF2407
Abstract: With the development of the technology in the adaptive filtering and the verylarge scale integration (VLSI), it offers the theory and technical support for studyingto cancel noises in communication system .In the system of communication ,theuseful signal is picked up from noise by the technology of adaptive filtering. It willhave the wide applicative prospect .The adaptive noise canceling system developsfrom the adaptive filtering system.It can improve the quality of signal by picking upand detecting the useful signal or canceling noise in the environment which wasinterfered by noise. The purpose of this dissertation is to design an adaptive noisecanceling system. The main task is divided into two parts. In the first part,the article intruduced the basic theory of adaptive filter andadptive noise canceling system .It analyse the index and function of the adaptive noise canceling system.The article intruduced and campare two basic algorithm,the LSM and RLS algorithm,and simulink by MATLAB and analyze the result of simulinking which prove the feasibility of the design and algorithm.In the second part,the task is to design the hardware and software for adaptive noise canceling system. On the foundation of the first part, puting up a design of canceling noise by taking advantage of DSP chip (TMS320LF2407),on which it realized the LMS algorithm .the article put forward a new method of testing DSP online,the system controlled by MCU(89551),and showed us the circuit diagram.At the end of the article,the author wrote out the flow diagram for programming and give out the list of programming.
Key Words: Adaptive Filter, Canceling Noises; LMS Algorithm, RLS Algorithm


參考文獻:
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[2]沈福民.自適應信號處理.西安:西安電子科技大學出版社，2000.9