微波传输线三种工作状态分析的MATLAB实现

(一)主程序变量说明：

输入变量：

zo 传输线特性阻抗

zl 传输线终端负载阻抗

Er 传输线介电常数

f 传输电磁波的频率

由输入变量计算得出的变量：

w 传输电磁波的数字角频率

len 传输电磁波的相波长

beita 相移常数

gama 传输线个点反射系数复值

gamal 传输线终端反射系数的模

rou 驻波系数

k 行波系数

Zi 传输线各点输入阻抗的复值

Ui 传输线各点输入电压的复值

Uo 传输线各点输出电压的复值

Uit 传输线各点输入电压的瞬时值

Uot 传输线各点输出电压的瞬时值

Ii 传输线各点输入电流的复值

Io 传输线各点输出电流的复值

Is 传输线各点合成电流的复值

Us 传输线各点合成电压的复值

Ist 传输线各点合成电流的瞬时值

Ust 传输线各点合成电压的瞬时值

ph 传输线各点合成电压的相位

(二)主程序流程说明：

本程序的界面中共有三个输入编辑框，三个输出编辑框和五个波形显示窗口，分别用来输入：传输线特性阻抗Z0、传输线终端负载阻抗Z L、传输的电磁波的频率f、传输线传输介质的相对介电常数εr；输出：传输线的终端反射系数ΓL、行波系数ρ、驻波系数K；

具体的程序思路如下：

1.由输入编辑框获得用户输入的Z0、Z L、f和εr；

2.在“开始”按钮的callback函数中进行运算，并控制各个axis的显示；

3.图形的动态显示由一个while循环实现，并由全局标记变量flag控制；

4.在“停止”按钮的callback函数中令flag = 1，while循环跳出。

(三)程序运行效果

1.行波演示

中端接匹配负载

zo = zl = 50Ω

2.驻波演示

1)终端短路

zo = 50Ω

zl = 0

2)终端开路

zo = 50Ω

zl = inf

3)终端接纯电抗负载

zo = 50Ω

zl = X * j

3.行驻波演示

(四)主程序代码

function varargout = StatusAnaly(varargin)

%********************************************************%

% Copyright (C), 2009-2012,Lyric %

% FileName: StatusAnaly.m %

% Author: Lyric %

% Version: 1.0 %

% Date: 2010-05-11 %

%********************************************************%

% STATUSANALY M-file for StatusAnaly.fig

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

% singleton*.

%

% H = STATUSANALY returns the handle to a new STATUSANALY or the handle to % the existing singleton*.

%

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

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

% STATUSANALY('Property','Value',...) creates a new STATUSANALY or raises the % existing singleton*. Starting from the left, property value pairs are

% applied to the GUI before StatusAnaly_OpeningFcn gets called. An

% unrecognized property name or invalid value makes property application

% stop. All inputs are passed to StatusAnaly_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 StatusAnaly

% Last Modified by GUIDE v2.5 11-May-2010 14:30:20

% Begin initialization code - DO NOT EDIT

gui_Singleton = 1;

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

'gui_Singleton', gui_Singleton, ...

'gui_OpeningFcn', @StatusAnaly_OpeningFcn, ...

'gui_OutputFcn', @StatusAnaly_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 StatusAnaly is made visible.

function StatusAnaly_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 StatusAnaly (see VARARGIN)

% Choose default command line output for StatusAnaly

handles.output = hObject;

% Update handles structure

guidata(hObject, handles);

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

% uiwait(handles.figure1);

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