自適應(yīng)噪聲抵消器的設(shè)計(jì)
1.6萬字 21頁


摘要：自適應(yīng)濾波技術(shù)的發(fā)展和超大規(guī)模集成電路(VLSI )技術(shù)的迅速發(fā)展與應(yīng)用，從理論和技術(shù)上為通信系統(tǒng)的降噪研究提供了技術(shù)支持。在通信系統(tǒng)中，采用合適的自適應(yīng)濾波技術(shù)，從被污染的信號中提取有用的信號有著廣闊的應(yīng)用前景。自適應(yīng)噪聲干擾抵消器是基于自適應(yīng)濾波原理的一種擴(kuò)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(zhì)量。本論文的目的在于設(shè)計(jì)一個自適應(yīng)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(dá)到提高語音信號質(zhì)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(yīng)數(shù)字濾波器的基本理論思想，具體闡述了自適應(yīng)噪聲抵消系統(tǒng)基本原理，并對自適應(yīng)噪聲抵消系統(tǒng)的指標(biāo)、抵消性能進(jìn)行了計(jì)算分析。最小均方誤差(LMS )算法和遞歸最小二乘((RLS)算法進(jìn)行了詳細(xì)的介紹和分析。并通過對自適應(yīng)噪聲抵消器的MATLAB仿真及對仿真圖形的分析，驗(yàn)證了系統(tǒng)設(shè)計(jì)和自適應(yīng)算法的可行性。第二部分主要完成自適應(yīng)噪聲抵消系統(tǒng)的硬件設(shè)計(jì)和軟件編程。在第一部分計(jì)算機(jī)仿真分析的基礎(chǔ)上，利用高速信號處理芯片DSP (TMS320LF2407)設(shè)計(jì)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(shí)現(xiàn)了自適應(yīng)LMS算法。在硬件方面，詳細(xì)介紹了利用單片機(jī)AT89S51對DSP系統(tǒng)進(jìn)行在線調(diào)試的具體過程，并給出了系統(tǒng)設(shè)計(jì)的詳細(xì)電路圖。在軟件方面，給出了自適應(yīng)噪聲抵消器LMS算法的軟件流程圖和相應(yīng)的程序。
關(guān)鍵詞:自適應(yīng)濾波，自適應(yīng)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


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