北京理工大学 数字信号处理 实验报告 程序

数字信号处理实验报告

1.深入掌握应用DFT分析信号的频谱的理论方法，针对该问题进行一次全面综合

练习，完成一个完整的信号分析软件实现方法和流程，这种全面完整的综合练习可以帮助学生深入理解和消化基本理论，锻炼学生独立解决问题的能力，培养学生的创新意识，为今后的科研和工作打下良好的实践基础。

2.综合利用数字信号处理的理论知识完成数字滤波器的设计与实现，完成一个完

整的数字滤波器设计软件的实现方法和流程。这种全面完整的综合练习可以帮助学生深入理解和消化基本理论，锻炼学生独立解决问题的能力，培养学生的创新意识，为今后的科研和工作打下良好的实践基础。

二、实验设备与环境

计算机、MATLAB软件环境

三、实验内容

1.基于Matlab GUI的离散傅里叶变换分析

2.基于Matlab GUI的数字滤波器分析设计

1.基于Matlab GUI的离散傅里叶变换分析

信号： t=1:100;

x=2*sin(t/25*2*pi)+5*sin(t/5*2*pi);

说明：输入信号从Matlab Command Windows中生成，通过变量名导入本软件，并可输出DFT变换后的结果，默认名为DFT_输入变量名。

2.基于Matlab GUI的数字滤波器分析设计

IIR 低通：（巴特沃兹）

IIR高通：（切比雪夫I）

IIR带通：（切比雪夫II）

IIR带阻：（椭圆滤波器）

FIR低通：（矩形窗）

FIR高通：（汉宁窗）

FIR带通：(布莱克曼窗)

FIR带阻：（凯瑟窗）

五、程序界面设计及程序源代码

1.基于Matlab GUI的离散傅里叶变换分析

界面设计：

程序代码：

function varargout =

SignalDFTSoftware(varargin)

% SIGNALDFTSOFTWARE MATLAB code for SignalDFTSoftware.fig

% SIGNALDFTSOFTWARE, by itself, creates a new SIGNALDFTSOFTWARE or raises the existing

% singleton*.

%% H = SIGNALDFTSOFTWARE returns the handle to a new SIGNALDFTSOFTWARE or the handle to

% the existing singleton*.

%%

SIGNALDFTSOFTWARE('CALLBACK',hObject,even tData,handles,...) calls the local

% function named CALLBACK in SIGNALDFTSOFTWARE.M with the given input arguments.

%%

SIGNALDFTSOFTWARE('Property','Value',...) creates a new SIGNALDFTSOFTWARE or raises the

% existing singleton*. Starting from the left, property value pairs are

% applied to the GUI before SignalDFTSoftware_OpeningFcn gets called.

An

% unrecognized property name or invalid value makes property application

% stop. All inputs are passed to SignalDFTSoftware_OpeningFcn via varargin. %% *See GUI Options on GUIDE's Tools menu. Choose "GUI allows only one

% instance to run (singleton)".

%% See also: GUIDE, GUIDATA, GUIHANDLES

% Edit the above text to modify the response to help SignalDFTSoftware

% Last Modified by GUIDE v2.5 26-Nov-2011 12:55:11

% Begin initialization code - DO NOT EDIT

gui_Singleton = 1;

gui_State = struct('gui_Name',

mfilename, ...

'gui_Singleton', gui_Singleton, ...

'gui_OpeningFcn',

@SignalDFTSoftware_OpeningFcn, ...

'gui_OutputFcn',

@SignalDFTSoftware_OutputFcn, ...

'gui_LayoutFcn', [] , ...

'gui_Callback', []);

if nargin&&ischar(varargin{1})

gui_State.gui_Callback = str2func(varargin{1}); end

if nargout

[varargout{1:nargout}] =

gui_mainfcn(gui_State, varargin{:});

else

gui_mainfcn(gui_State, varargin{:});

end

% End initialization code - DO NOT EDIT

% --- Executes just before SignalDFTSoftware is made visible.

function SignalDFTSoftware_OpeningFcn(hObjec t, eventdata, handles, varargin)

% This function has no output args, see OutputFcn.

% hObject handle to figure

% eventdata reserved - to be defined in a future version of MATLAB

% varargin command line arguments to SignalDFTSoftware (see VARARGIN)

% Choose default command line output for SignalDFTSoftware

handles.output = hObject;

% Update handles structure guidata(hObject, handles);

% UIWAIT makes SignalDFTSoftware wait for user response (see UIRESUME)

% uiwait(handles.figure1);

% --- Outputs from this function are returned to the command line.

function varargout =

SignalDFTSoftware_OutputFcn(hObject, eventdata, handles)

% varargout cell array for returning output args (see VARARGOUT);

% hObject handle to figure

% eventdata reserved - to be defined in a future version of MATLAB

% Get default command line output from handles structure

varargout{1} = handles.output;

% --- If Enable == 'on', executes on mouse press in 5 pixel border.

% --- Otherwise, executes on mouse press in 5 pixel border or over random.

function random_ButtonDownFcn(hObject, eventdata, handles)

% hObject handle to random (see GCBO)

% eventdata reserved - to be defined in a future version of MATLAB

% --- Executes on button press in random. function random_Callback(hObject, eventdata, handles)

% hObject handle to random (see GCBO)

% eventdata reserved - to be defined in a future version of MATLAB

global x;

global x_flag;

x=rand(1,50)*20-10;

x_flag=1;

if(x_flag)

plot(handles.TD,0:(length(x)-1),x);

end

% --- Executes on button press in Delete.