%***********************************************************************
%?????1-D?FDTD?code?with?simple?radiation?boundary?conditions
%***********************************************************************
%
%?????Program?author:?Susan?C.?Hagness
%?????????????????????Department?of?Electrical?and?Computer?Engineering
%?????????????????????University?of?Wisconsin-Madison
%?????????????????????1415?Engineering?Drive
%?????????????????????Madison?WI?53706-1691
%?????????????????????608-265-5739
%?????????????????????hagness@engr.wisc.edu
%
%?????Date?of?this?version:??February?2000
%
%?????This?MATLAB?M-file?implements?the?finite-difference?time-domain
%?????solution?of?Maxwell‘s?curl?equations?over?a?one-dimensional?space
%?????lattice?comprised?of?uniform?grid?cells.
%
%?????To?illustrate?the?algorithm?a?sinusoidal?wave?（1GHz）?propagating?
%?????in?a?nonpermeable?lossy?medium?（epsr=1.0?sigma=5.0e-3?S/m）?is?
%?????modeled.??The?simplified?finite?difference?system?for?nonpermeable
%?????media?（discussed?in?Section?3.6.6?of?the?text）?is?implemented.
%
%?????The?grid?resolution?（dx?=?1.5?cm）?is?chosen?to?provide?20
%?????samples?per?wavelength.??The?Courant?factor?S=c*dt/dx?is?set?to
%?????the?stability?limit:?S=1.??In?1-D?this?is?the?“magic?time?step.“
%
%?????The?computational?domain?is?truncated?using?the?simplest?radiation
%?????boundary?condition?for?wave?propagation?in?free?space:?
%
%??????????????????????Ez（imaxn+1）?=?Ez（imax-1n）
%
%?????To?execute?this?M-file?type?“fdtd1D“?at?the?MATLAB?prompt.
%?????This?M-file?displays?the?FDTD-computed?Ez?and?Hy?fields?at?every?
%?????time?step?and?records?those?frames?in?a?movie?matrix?M?which?is
%?????played?at?the?end?of?the?simulation?using?the?“movie“?command.
%
%***********************************************************************

clear

%***********************************************************************
%?????Fundamental?constants
%***********************************************************************

cc=2.99792458e8;????????????%speed?of?light?in?free?space
muz=4.0*pi*1.0e-7;??????????%permeability?of?free?space
epsz=1.0/（cc*cc*muz）;???????%permittivity?of?free?space

freq=1.0e+9;????????????????%frequency?of?source?excitation
lambda=cc/freq;?????????????%wavelength?of?source?excitation
omega=2.0*pi*freq;

%***********************************************************************
%?????Grid?parameters
%***********************************************************************

ie=200;?????????????????????%number?of?grid?cells?in?x-direction

ib=ie+1;

dx=lambda/20.0;?????????????%space?increment?of?1-D?lattice
dt=dx/cc;???????????????????%time?step
omegadt=omega*dt;

nmax=round（12.0e-9/dt）;?????%total?number?of?time?steps

%***********************************************************************
%?????Material?parameters
%***********************************************************************

eps=1.0;
sig=5.0e-

?屬性????????????大小?????日期????時(shí)間???名稱
-----------?---------??----------?-----??----

?????文件???????5465??2007-11-19?22:08??fdtd1D.m

?????文件??????19909??2007-11-19?22:08??fdtd2D.m

?????文件???????7828??2007-11-19?22:08??fdtd3D.m

-----------?---------??----------?-----??----

????????????????33202????????????????????3