自适应滤波器设计及Matlab实现附程序代码整理版.doc

维纳自适应?滤波器设计?及Matl?ab实现

摘 要

本文从随机?噪声的特性?出发，分析了传统?滤波和自适?应滤波基本?工作原理和?性能，以及滤波技?术的现状和?发展前景。然后系统阐?述了基本维?纳滤波原理?和自适应滤?波器的基本?结构模型，接着在此基?础上结合最?陡下降法引?出LMS算?法。在MSE准?则下，设计了一个?定长的自适?应最小均方?横向滤波器?，并通过MA?TLAB编?程实现。接着用图像?复原来验证?该滤波器的?性能，结果表明图?像的质量在?MSE准则?下得到了明?显的改善。最后分析比?较了自适应?LMS滤波?和频域维纳?递归滤波之?间的性能。本文还对M?ATLAB?里面的自适?应维纳滤波?函数wie?ner2进?行了简单分?析。

关键字：退化图像 维纳滤波自适应滤波?最陡下降法? LMS

Abstr?act

This paper? analy?ses the basic? work theor?y, perfo?rmanc?e of tradi?tiona?l filte?r and adapt?ive filte?r based? on the prope?rty of rando?m noise?, and intro?duce the statu?s quo and the foreg?round? of filte?r techn?ology?. Then we expla?in basic? theor?y of wiene?r filte?r and basic? struc?ture model? of adapt?ive filte?r, and combi?ne the metho?d of steep?est desce?nt to deduc?e the LMS. After?ward accor?ding to the MSE rule, we desig?n a limit?ed lengt?h trans?versa?l filte?r, and imple?ment by MATLA?B. And then we valid?ate perfo?rmanc?e of adapt?ive LMS filte?r by resto?ring image?s, Test resul?t show that the quali?ty of the degra?de image?s were impro?ved under? the rule of MSE. Final?ly, we compa?re the perfo?rmanc?e of adapt?ive LMS filte?r and itera?tive wiene?r filte?r.

We also simpl?y analy?ses the wiene?r2 () which? is a adapt?ive filte?r in MATLA?B.

Keywo?rds: degra?de image?；wiene?r filte?r；adapt?ive filte?r；ADF；LMS algor?ithm

目录

绪论…………………………………………………………………………………1

1. 1 引言…………………………………………………………………………1

1. 2 研究目标及?现状……………………………………………………………1

1. 2 .1 图像复原技?术的目标……………………………………………1

1. 2 .2 图像复原技?术的研究现?状………………………………………1

理论基础 …………………………………………………………………………3

2. 1 基本自适应?滤波器的模?块结构……………………………………………3

2. 2 基本维纳滤?波原理…………………………………………………………4

自适应滤波?原理及算法? ………………………………………………………6

3.1 横向滤波结?构的最陡下?降算法……………………………………………7

3.1.1 最陡下降算?法的原理……………………………………………7

3.1.2 最陡下降算?法稳定性……………………………………………10

3.2 LMS滤波?原理及算法?……………………………………………………11

3.2.1 从最陡下降?算法导出L?MS算法 ………………………………11

3.2.2 基本LMS?算法的实现?步骤 ……………………………………11

3.2.3 基本LMS?算法的实现?流程图 …………………………………12

3.2.4 LMS算法?的Matl?ab实现 ………………………………………12

3.2.5