一、数字滤波器设计简介(附课题作业报告)

1 设计原理

1.1 滤波器概念

1.2 数字滤波器的系统函数和差分方程

1.3 数字滤波器结构的表示


1.4 数字滤波器的分类


2.1 IIR滤波器与FIR滤波器的分析比较

2.2 FIR滤波器的原理








3 FIR滤波器的仿真步骤

二、部分源代码

function varargout = Filter(varargin)
% FILTER M-file for Filter.fig
%      FILTER, by itself, creates a new FILTER or raises the existing
%      singleton*.
%
%      H = FILTER returns the handle to a new FILTER or the handle to
%      the existing singleton*.
%
%      FILTER('CALLBACK',hObject,eventData,handles,...) calls the local
%      function named CALLBACK in FILTER.M with the given input arguments.
%
%      FILTER('Property','Value',...) creates a new FILTER or raises the
%      existing singleton*.  Starting from the left, property value pairs are
%      applied to the GUI before Filter_OpeningFunction gets called.  An
%      unrecognized property name or invalid value makes property application
%      stop.  All inputs are passed to Filter_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 Filter

% Last Modified by GUIDE v2.5 03-Jun-2021 01:02:47

% Begin initialization code - DO NOT EDIT
gui_Singleton = 1;
gui_State = struct('gui_Name',       mfilename, ...
                   'gui_Singleton',  gui_Singleton, ...
                   'gui_OpeningFcn', @Filter_OpeningFcn, ...
                   'gui_OutputFcn',  @Filter_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 Filter is made visible.
function Filter_OpeningFcn(hObject, 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
% handles    structure with handles and user data (see GUIDATA)
% varargin   command line arguments to Filter (see VARARGIN)

% Choose default command line output for Filter
handles.output = hObject;

% Update handles structure
guidata(hObject, handles);

% UIWAIT makes Filter wait for user response (see UIRESUME)
% uiwait(handles.figure1);


% --- Outputs from this function are returned to the command line.
function varargout = Filter_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
% handles    structure with handles and user data (see GUIDATA)

% Get default command line output from handles structure
varargout{1} = handles.output;



function Fs_Callback(hObject, eventdata, handles)
% hObject    handle to Fs (see GCBO)
% eventdata  reserved - to be defined in a future version of MATLAB
% handles    structure with handles and user data (see GUIDATA)

% Hints: get(hObject,'String') returns contents of Fs as text
%        str2double(get(hObject,'String')) returns contents of Fs as a double


% --- Executes during object creation, after setting all properties.
function Fs_CreateFcn(hObject, eventdata, handles)
% hObject    handle to Fs (see GCBO)
% eventdata  reserved - to be defined in a future version of MATLAB
% handles    empty - handles not created until after all CreateFcns called

% Hint: edit controls usually have a white background on Windows.
%       See ISPC and COMPUTER.
if ispc && isequal(get(hObject,'BackgroundColor'), get(0,'defaultUicontrolBackgroundColor'))
    set(hObject,'BackgroundColor','white');
end



function Fp1_Callback(hObject, eventdata, handles)
%检查输入的通带边缘频率是否【0，1】
Fs_value=str2double(get(handles.Fs,'String'));
Fp1_value=str2double(get(handles.Fp1,'String'));
wp1=2*Fp1_value/Fs_value;
if(wp1>=1)
    errordlg('wp1=2*Fp1/Fs, 归一化频率不在【0，1】范围内，请输入正确的参数','错误信息') 
end
% hObject    handle to Fp1 (see GCBO)
% eventdata  reserved - to be defined in a future version of MATLAB
% handles    structure with handles and user data (see GUIDATA)

% Hints: get(hObject,'String') returns contents of Fp1 as text
%        str2double(get(hObject,'String')) returns contents of Fp1 as a double


% --- Executes during object creation, after setting all properties.
function Fp1_CreateFcn(hObject, eventdata, handles)
% hObject    handle to Fp1 (see GCBO)
% eventdata  reserved - to be defined in a future version of MATLAB
% handles    empty - handles not created until after all CreateFcns called

% Hint: edit controls usually have a white background on Windows.
%       See ISPC and COMPUTER.
if ispc && isequal(get(hObject,'BackgroundColor'), get(0,'defaultUicontrolBackgroundColor'))
    set(hObject,'BackgroundColor','white');
end



function Fp2_Callback(hObject, eventdata, handles)
%检查输入的通带边缘频率是否【0，1】
Fs_value=str2double(get(handles.Fs,'String'));
Fp2_value=str2double(get(handles.Fp2,'String'));
wp2=2*Fp2_value/Fs_value;
if(wp2>=1)
    errordlg('wp2=2*Fp2/Fs, 归一化频率不在【0，1】范围内，请输入正确的参数','错误信息') 
end
% hObject    handle to Fp2 (see GCBO)
% eventdata  reserved - to be defined in a future version of MATLAB
% handles    structure with handles and user data (see GUIDATA)

% Hints: get(hObject,'String') returns contents of Fp2 as text
%        str2double(get(hObject,'String')) returns contents of Fp2 as a double


% --- Executes during object creation, after setting all properties.
function Fp2_CreateFcn(hObject, eventdata, handles)
% hObject    handle to Fp2 (see GCBO)
% eventdata  reserved - to be defined in a future version of MATLAB
% handles    empty - handles not created until after all CreateFcns called

% Hint: edit controls usually have a white background on Windows.
%       See ISPC and COMPUTER.
if ispc && isequal(get(hObject,'BackgroundColor'), get(0,'defaultUicontrolBackgroundColor'))
    set(hObject,'BackgroundColor','white');
end



function Fs1_Callback(hObject, eventdata, handles)
%检查输入的阻带边缘频率是否【0，1】
Fs_value=str2double(get(handles.Fs,'String'));
Fs1_value=str2double(get(handles.Fs1,'String'));
ws1=2*Fs1_value/Fs_value;
if(ws1>=1)
    errordlg('ws1=2*Fs1/Fs, 归一化频率不在【0，1】范围内，请输入正确的参数','错误信息') 
end
% hObject    handle to Fs1 (see GCBO)
% eventdata  reserved - to be defined in a future version of MATLAB
% handles    structure with handles and user data (see GUIDATA)

% Hints: get(hObject,'String') returns contents of Fs1 as text
%        str2double(get(hObject,'String')) returns contents of Fs1 as a double


% --- Executes during object creation, after setting all properties.
function Fs1_CreateFcn(hObject, eventdata, handles)
% hObject    handle to Fs1 (see GCBO)
% eventdata  reserved - to be defined in a future version of MATLAB
% handles    empty - handles not created until after all CreateFcns called

% Hint: edit controls usually have a white background on Windows.
%       See ISPC and COMPUTER.
if ispc && isequal(get(hObject,'BackgroundColor'), get(0,'defaultUicontrolBackgroundColor'))
    set(hObject,'BackgroundColor','white');
end



function Fs2_Callback(hObject, eventdata, handles)
%检查输入的阻带边缘频率是否【0，1】
Fs_value=str2double(get(handles.Fs,'String'));
Fs2_value=str2double(get(handles.Fs2,'String'));
ws2=2*Fs2_value/Fs_value;
if(ws2>=1)
    errordlg('ws2=2*Fs2/Fs, 归一化频率不在【0，1】范围内，请输入正确的参数','错误信息') 
end
% hObject    handle to Fs2 (see GCBO)
% eventdata  reserved - to be defined in a future version of MATLAB
% handles    structure with handles and user data (see GUIDATA)

% Hints: get(hObject,'String') returns contents of Fs2 as text
%        str2double(get(hObject,'String')) returns contents of Fs2 as a double


% --- Executes during object creation, after setting all properties.
function Fs2_CreateFcn(hObject, eventdata, handles)
% hObject    handle to Fs2 (see GCBO)
% eventdata  reserved - to be defined in a future version of MATLAB
% handles    empty - handles not created until after all CreateFcns called

% Hint: edit controls usually have a white background on Windows.
%       See ISPC and COMPUTER.
if ispc && isequal(get(hObject,'BackgroundColor'), get(0,'defaultUicontrolBackgroundColor'))
    set(hObject,'BackgroundColor','white');
end



function Rp_Callback(hObject, eventdata, handles)
% hObject    handle to Rp (see GCBO)
% eventdata  reserved - to be defined in a future version of MATLAB
% handles    structure with handles and user data (see GUIDATA)

% Hints: get(hObject,'String') returns contents of Rp as text
%        str2double(get(hObject,'String')) returns contents of Rp as a double


% --- Executes during object creation, after setting all properties.
function Rp_CreateFcn(hObject, eventdata, handles)
% hObject    handle to Rp (see GCBO)
% eventdata  reserved - to be defined in a future version of MATLAB
% handles    empty - handles not created until after all CreateFcns called

% Hint: edit controls usually have a white background on Windows.
%       See ISPC and COMPUTER.
if ispc && isequal(get(hObject,'BackgroundColor'), get(0,'defaultUicontrolBackgroundColor'))
    set(hObject,'BackgroundColor','white');
end



function Rs_Callback(hObject, eventdata, handles)
% hObject    handle to Rs (see GCBO)
% eventdata  reserved - to be defined in a future version of MATLAB
% handles    structure with handles and user data (see GUIDATA)

% Hints: get(hObject,'String') returns contents of Rs as text
%        str2double(get(hObject,'String')) returns contents of Rs as a double


% --- Executes during object creation, after setting all properties.
function Rs_CreateFcn(hObject, eventdata, handles)
% hObject    handle to Rs (see GCBO)
% eventdata  reserved - to be defined in a future version of MATLAB
% handles    empty - handles not created until after all CreateFcns called

% Hint: edit controls usually have a white background on Windows.
%       See ISPC and COMPUTER.
if ispc && isequal(get(hObject,'BackgroundColor'), get(0,'defaultUicontrolBackgroundColor'))
    set(hObject,'BackgroundColor','white');
end


% --- Executes on selection change in FilterDesign.
function FilterDesign_Callback(hObject, eventdata, handles)
  AutoRun_value=get(handles.AutoRun,'Value');
  if(AutoRun_value==1)
     AutoChoose(handles)
  end

% hObject    handle to FilterDesign (see GCBO)
% eventdata  reserved - to be defined in a future version of MATLAB
% handles    structure with handles and user data (see GUIDATA)

% Hints: contents = get(hObject,'String') returns FilterDesign contents as cell array
%        contents{get(hObject,'Value')} returns selected item from FilterDesign


% --- Executes during object creation, after setting all properties.
function FilterDesign_CreateFcn(hObject, eventdata, handles)
% hObject    handle to FilterDesign (see GCBO)
% eventdata  reserved - to be defined in a future version of MATLAB
% handles    empty - handles not created until after all CreateFcns called

% Hint: popupmenu controls usually have a white background on Windows.
%       See ISPC and COMPUTER.
if ispc && isequal(get(hObject,'BackgroundColor'), get(0,'defaultUicontrolBackgroundColor'))
    set(hObject,'BackgroundColor','white');
end

三、运行结果

四、matlab版本及参考文献

1 matlab版本
2014a

2 参考文献
[1] 沈再阳.精通MATLAB信号处理[M].清华大学出版社，2015.
[2]高宝建,彭进业,王琳,潘建寿.信号与系统——使用MATLAB分析与实现[M].清华大学出版社，2020.
[3]王文光,魏少明,任欣.信号处理与系统分析的MATLAB实现[M].电子工业出版社，2018.