根据matlab的码型转换

.-

实验内容：

利用Matlab软件的GUI界面编程，做一个简单的界面，通过此界面调用相关的程序去实现由抽样判决后的AMI码型、CMI码型和HDB3码型数字序列恢复出原始的PCM脉冲编码信号。

实验目的：

1,熟悉Matlab的GUI的编程操作，学会运用GUI来建立一个界面

2.掌握AMI,CMI,HDB3码型的特点和意义，学会将PCM脉冲编码信号转化为AMI,CMI,HDB3的编码以及AMI,CMI,HDB3解码的方式。

实验方法：

实验中采用的方法是先建立大概的界面，其中包括输入框、按钮、提示内容及坐标系等。然后再对各种组件设置好属性，并对各个组件编写回调函数，最后进行调试验证饥渴。

实验代码：

1. AMI码型转换：

%%%%%%%%%%%% 编码 %%%%%%%%%%%%%

p = -1;

for i=1:length(f);

if f(i)==1

e(i) = (-1)*p;

p = e(i);

else

e(i) = f(i);

end

end

%%%%%%%%%%%% 译码 %%%%%%%%%%%%

for i=1:length(f);

.-

if e(i)~=0

l(i) = 1;

else

e(i) = 0;

end

end

编码：代码中的f代表着输入字符串转化后的ASCII码，用变量p来实现原信号中1的正负交替。例如，f（1）=1，则e（1）=1，p=1；f（2）=1，则e（2）=-1，p=-1。如此就可以得到正负1交替了。

译码：当e（i）不等于0，就把结果等于1。

2. CMI码型转换

%%%%%%%%%%%% 编码 %%%%%%%%%%%%%

m=1;

p=-1;

for i=1:length(f)

if(f(i)==1&m==1)

s(i)=3;

m=m*p;

else if(f(i)==1&m==-1)

s(i)=0;

m=m*p;

else

s(i)=1;

end

end

end

k=dec2bin(s,2);

l=k';

x=l(:);

y=x';

n=str2num(y(1));

for i=2:length(y)

n=[n str2num(y(i))];

end

%%%%%%%%%%%% 译码 %%%%%%%%%%%%%

if n(1)==0

if n(2)==1

cm=[0];

else

cm=[1];

end

else

cm=[1];

.-

end

r=3;

while r

if n(r)==0

if n(r+1)==1

cm=[cm 0];

else

cm=[cm 1];

end

else

cm=[cm 1];

end

r=r+2;

end

3. HDB3码型转换

%%%%%%%%%%%% 编码 %%%%%%%%%%%%%

yn=xn;% 输出yn初始化

num=0;% 计数器初始化

for k=1:length(xn)

if xn(k)==1

num=num+1; % "1"计数器

if num/2 == fix(num/2) % 奇数个1时输出-1,进行极性交替

yn(k)=1;

else

yn(k)=-1;

end

end

end

% HDB3编码

num=0; % 连零计数器初始化

yh=yn; % 输出初始化

sign=0; % 极性标志初始化为0

V=zeros(1,length(yn));% V脉冲位置记录变量

B=zeros(1,length(yn));% B脉冲位置记录变量

for k=1:length(yn)

if yn(k)==0

num=num+1; % 连“0”个数计数

if num==4 % 如果4连“0”

num=0; % 计数器清零

yh(k)=1*yh(k-4);

% 让0000的最后一个0改变为与前一个非零符号相同极性的符号

V(k)=yh(k); % V脉冲位置记录

.-

if yh(k)==sign % 如果当前V符号与前一个V符号的极性相同

yh(k)=-1*yh(k); % 则让当前V符号极性反转,以满足V符号间相互极性反转要求

yh(k-3)=yh(k); % 添加B符号,与V符号同极性

B(k-3)=yh(k); % B脉冲位置记录

V(k)=yh(k); % V脉冲位置记录

yh(k+1:length(yn))=-1*yh(k+1:length(yn));

% 并让后面的非零符号从V符号开始再交替变化

end

sign=yh(k); % 记录前一个V符号的极性

end

else

num=0; % 当前输入为“1”则连“0”计数器清零

end

end

%%%%%%%%%%%% 译码 %%%%%%%%%%%%%

input=yh; % HDB3码输入

decode=input; % 输出初始化

sign=0; % 极性标志初始化

for k=1:length(yh)

if input(k) ~= 0

if sign==yh(k) % 如果当前码与前一个非零码的极性相同

decode(k-3:k)=[0 0 0 0];% 则该码判为V码并将*00V清零

end

sign=input(k); % 极性标志

end

end

decode=abs(decode); % 整流

实验现象：

总体界面：

.-

AMI：

CMI：

HDB3：

.-

总结：

1. 本次实验中因为对画方波不太熟悉，在使用stairs函数时，方波图总是在最后少了一位，后来经查询后才知道stairs的正确用法。

2. 由于对GUI界面设置的不熟悉，很多细节都没做到位，界面的美观有待提高。

3. 在编代码是经常没有写注释，导致后来有些变量混淆了。

附录：全部代码

function varargout = untitled1(varargin)

% UNTITLED1 M-file for

% UNTITLED1, by itself, creates a new UNTITLED1 or raises the

existing

% singleton*.

%

% H = UNTITLED1 returns the handle to a new UNTITLED1 or the

handle to

% the existing singleton*.

%

% UNTITLED1('CALLBACK',hObject,eventData,handles,...) calls the

local

% function named CALLBACK in UNTITLED1.M with the given input

arguments.

%

.-

% UNTITLED1('Property','Value',...) creates a new UNTITLED1 or

raises the

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

pairs are

% applied to the GUI before untitled1_OpeningFunction gets

called. An

% unrecognized property name or invalid value makes property

application

% stop. All inputs are passed to untitled1_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 untitled1

% Last Modified by GUIDE v2.5 21-Dec-2014 19:55:20

% Begin initialization code - DO NOT EDIT

gui_Singleton = 1;

gui_State = struct('gui_Name', mfilename, ...

'gui_Singleton', gui_Singleton, ...

'gui_OpeningFcn', @untitled1_OpeningFcn, ...

'gui_OutputFcn', @untitled1_OutputFcn, ...

'gui_LayoutFcn', [] , ...

'gui_Callback', []);

if nargin && ischar(varargin{1})

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 untitled1 is made visible.

function untitled1_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 untitled1 (see VARARGIN)

% Choose default command line output for untitled1

= hObject;

% Update handles structure

guidata(hObject, handles);

% UIWAIT makes untitled1 wait for user response (see UIRESUME)

% uiwait();

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

function varargout = untitled1_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} = ;

function edit_Callback(hObject, eventdata, handles)

% hObject handle to edit (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 edit as text

% str2double(get(hObject,'String')) returns contents of edit as

a double

% --- Executes during object creation, after setting all properties.

function edit_CreateFcn(hObject, eventdata, handles)

% hObject handle to edit (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 button press in ami.

function ami_Callback(hObject, eventdata, handles)

user_string=get(,'string');

a=dec2bin(user_string,8);

b=a';

c=b(:);

d=c';

f=str2num(d(1));

for i=2:length(d)

f=[f str2num(d(i))];

end

f=[f 0];

%%%%%%%%%%%% ±àÂë %%%%%%%%%%%%%

p = -1;

for i=1:length(f);

if f(i)==1

e(i) = (-1)*p;

p = e(i);

else

e(i) = f(i);

end

end

%%%%%%%%%%%% ÒëÂë %%%%%%%%%%%%

for i=1:length(f);

if e(i)~=0

l(i) = 1;

else

e(i) = 0;

end

end

axes(1)

t=1:length(f);

stairs(t-1,f)

axis([0 length(f) -2 2])

xlabel('ASCIIÂë');

grid minor;

.-

axes(2)

t=1:length(e);

stairs(t-1,e)

axis([0 length(e) -2 2])

xlabel('AMI ±àÂë');

grid minor;

axes(3)

t=1:length(l);

stairs(t-1,l)

axis([0 length(l) -2 2])

xlabel('AMI ÒëÂë');

grid minor;

% hObject handle to ami (see GCBO)

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

% handles structure with handles and user data (see GUIDATA)

% --- Executes on button press in cmi.

function cmi_Callback(hObject, eventdata, handles)

user_string=get(,'string');

a=dec2bin(user_string,8);

b=a';

c=b(:);

d=c';

f=str2num(d(1));

for i=2:length(d)

f=[f str2num(d(i))];

end

f=[f 0];

%%%%%%%%%%%% ±àÂë %%%%%%%%%%%%%

m=1;

p=-1;

for i=1:length(f)

if(f(i)==1&m==1)

s(i)=3;

m=m*p;

else if(f(i)==1&m==-1)

s(i)=0;

m=m*p;

else

s(i)=1;

end

end

end

.-

k=dec2bin(s,2);

l=k';

x=l(:);

y=x';

n=str2num(y(1));

for i=2:length(y)

n=[n str2num(y(i))];

end

%%%%%%%%%%%% ÒëÂë %%%%%%%%%%%%%

if n(1)==0

if n(2)==1

cm=[0];

else

cm=[1];

end

else

cm=[1];

end

r=3;

while r

if n(r)==0

if n(r+1)==1

cm=[cm 0];

else

cm=[cm 1];

end

else

cm=[cm 1];

end

r=r+2;

end

axes(1)

t=1:length(f);

stairs(t-1,f)

axis([0 length(f) -2 2])

xlabel('ASCIIÂë');

grid minor;

axes(2)

t=1:length(n);

stairs(t-1,n)

axis([0 length(n) -2 2])

xlabel('CMI ±àÂë');

grid minor;

axes(3)

.-

t=1:length(cm);

stairs(t-1,cm)

axis([0 length(cm) -2 2])

xlabel('CMI ÒëÂë');

grid minor;

% hObject handle to cmi (see GCBO)

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

% handles structure with handles and user data (see GUIDATA)

% --- Executes on button press in hdb3.

function hdb3_Callback(hObject, eventdata, handles)

user_string=get(,'string');

a=dec2bin(user_string,8);

b=a';

b=a';

c=b(:);

d=c';

xn=str2num(d(1));

for i=2:length(d)

xn=[xn str2num(d(i))];

end

xn=[xn 0];

%%%%%%%%%%%% ±àÂë %%%%%%%%%%%%%

yn=xn;% Êä³öyn³õʼ»¯

num=0;% ¼ÆÊýÆ÷³õʼ»¯

for k=1:length(xn)

if xn(k)==1

num=num+1; % "1"¼ÆÊýÆ÷

if num/2 == fix(num/2) % ÆæÊý¸ö1ʱÊä³ö-1,½øÐм«ÐÔ½»Ìæ

yn(k)=1;

else

yn(k)=-1;

end

end

end

% HDB3±àÂë

num=0; % Á¬Áã¼ÆÊýÆ÷³õʼ»¯

yh=yn; % Êä³ö³õʼ»¯

sign=0; % ¼«ÐÔ±êÖ¾³õʼ»¯Îª0

V=zeros(1,length(yn));% VÂö³åλÖüǼ±äÁ¿

B=zeros(1,length(yn));% BÂö³åλÖüǼ±äÁ¿

for k=1:length(yn)

if yn(k)==0

.-

num=num+1; % Á¬¡°0¡±¸öÊý¼ÆÊý

if num==4 % Èç¹û4Á¬¡°0¡±

num=0; % ¼ÆÊýÆ÷ÇåÁã

yh(k)=1*yh(k-4);

%

ÈÃ0000µÄ×îºóÒ»¸ö0¸Ä±äΪÓëÇ°Ò»¸ö·ÇÁã·ûºÅÏàͬ¼«ÐԵķûºÅ

V(k)=yh(k); % VÂö³åλÖüǼ

if yh(k)==sign % Èç¹ûµ±Ç°V·ûºÅÓëÇ°Ò»¸öV·ûºÅµÄ¼«ÐÔÏàͬ

yh(k)=-1*yh(k); %

ÔòÈõ±Ç°V·ûºÅ¼«ÐÔ·´×ª,ÒÔÂú×ãV·ûºÅ¼äÏ໥¼«ÐÔ·´×ªÒªÇó

yh(k-3)=yh(k); % Ìí¼ÓB·ûºÅ,ÓëV·ûºÅͬ¼«ÐÔ

B(k-3)=yh(k); % BÂö³åλÖüǼ

V(k)=yh(k); % VÂö³åλÖüǼ

yh(k+1:length(yn))=-1*yh(k+1:length(yn));

% ²¢ÈúóÃæµÄ·ÇÁã·ûºÅ´ÓV·ûºÅ¿ªÊ¼ÔÙ½»Ìæ±ä»¯

end

sign=yh(k); % ¼Ç¼ǰһ¸öV·ûºÅµÄ¼«ÐÔ

end

else

num=0; % µ±Ç°ÊäÈëΪ¡°1¡±ÔòÁ¬¡°0¡±¼ÆÊýÆ÷ÇåÁã

end

end

%%%%%%%%%%%% ÒëÂë %%%%%%%%%%%%%

input=yh; % HDB3ÂëÊäÈë

decode=input; % Êä³ö³õʼ»¯

sign=0; % ¼«ÐÔ±êÖ¾³õʼ»¯

for k=1:length(yh)

if input(k) ~= 0

if sign==yh(k) % Èç¹ûµ±Ç°ÂëÓëÇ°Ò»¸ö·ÇÁãÂëµÄ¼«ÐÔÏàͬ

decode(k-3:k)=[0 0 0 0];% Ôò¸ÃÂëÅÐΪVÂë²¢½«*00VÇåÁã

end

sign=input(k); % ¼«ÐÔ±êÖ¾

end

end

decode=abs(decode); % ÕûÁ÷

axes(1)

t=1:length(xn);

stairs(t-1,xn)

axis([0 length(xn) -2 2])

xlabel('ASCIIÂë');

grid minor;

axes(2)

t=1:length(yh);

stairs(t-1,yh)

.-

axis([0 length(yh) -2 2])

xlabel('HDB3 ±àÂë');

grid minor;

axes(3)

t=1:length(decode);

stairs(t-1,decode)

axis([0 length(decode) -2 2])

xlabel('HDB3 ÒëÂë');

grid minor;

% hObject handle to hdb3 (see GCBO)

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

% handles structure with handles and user data (see GUIDATA)

% --- Executes when plent is resized.

function plent_ResizeFcn(hObject, eventdata, handles)

% hObject handle to plent (see GCBO)

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

% handles structure with handles and user data (see GUIDATA)

% --------------------------------------------------------------------

function plent_ButtonDownFcn(hObject, eventdata, handles)

% hObject handle to plent (see GCBO)

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

% handles structure with handles and user data (see GUIDATA)

% --- Executes during object creation, after setting all properties.

function plent_CreateFcn(hObject, eventdata, handles)

% hObject handle to plent (see GCBO)

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

% handles empty - handles not created until after all CreateFcns

called