[已解决]Sullivan 写的两个程序FDTD1D_1.5和FDTD_2.1模拟相同的情景为什么输出的结果不同呀

哪位高手指点下：Sullivan 写的两个程序FDTD1D_1.5和FDTD_2.1模拟相同的情景（即正弦波通过损耗介质）为什么输出的结 .. {$.{VE+v5  
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两个都是1D的？ ~ M"[FYw[  
代码贴出来？

FDTD1D_1.5 d&fENnt?h  
f_ ::?  
r1[0#5kJ;J  
delta_x = .01;%Set the cell size to 1cm -0W;b"]+A  
delta_t = delta_x/(2*3e8);%Calculate the time step -Oo$\=d  
max_time = 500;% time is be limited Y-Z.AA,  
max_space = 200; 'd28YjtoX  
E = zeros(max_space,1); F4k`x/ak  
H = E; G~_dSa@g G  
dielectric_begin = 100; , w_Ew  
dielectric_end = max_space; IE|$>q0Z  
dielectic_space_a = ones(max_space,1); R4o_zwWgPw  
dielectic_space_b = ones(max_space,1); 7~IAgjo,@  
eta = 0.5; M]&9Kg3  
dielectric_constant = 4; +pE-Yn`YS  
etaeps = eta/dielectric_constant; 8\[6z0+;  
%Lossy Medium variables - for non-Lossy medium set sigma = 0; s)-=l_4T  
sigma = 0.04; iR_X,&p   
epszero = 8.85419e-12; $FD0MrB_+  
loss_term = (delta_t*sigma) / (2*epszero*dielectric_constant); a.q
=  
%ABS needed for LHS of problem space do not work with Lossy medium nY6^DE2f  
E_low_m2 = 0; 3D\I#g  
E_low_m1 = 0; zW\&q!`IRP  
E_high_m2 = 0; %=GnGgu  
E_high_m1 = 0; RhYf+?2  
%Initialize Pulse Variables fSSDOH!U,  
frequency = 700*1e6;% Unit of Mhz -{ZRk[>Z  
place_pulse = 5; vmL0H)q  
% center_problem_space = max_space/2; @k6>&PS  
%Set up dielectric medium within the problem space rtOXK4)]I  
for i = 1:max_space "*?^'(yA@  
if (i>=dielectric_begin & i <= dielectric_end) ?-6oh~W<  
dielectric_space_a(i)=(1-loss_term)/(1+loss_term); HogT#BMs  
dielectric_space_b(i)=0.5/(dielectric_constant *(1+loss_term)); c$>Tfa'H  
else /S]<MS  
dielectric_space_a(i)=1; :]:q=1;c  
dielectric_space_b(i)=eta; Qq>M}  
end +Ge-!&.;A  
end }"A.[9 b  
for n = 1:max_time kvKbl;<&#  
for k = 2:max_space b]@^SN9  
E(k) = dielectric_space_a(k)*E(k) + dielectric_space_b(k)*(H(k-1)-H(k)); 58WL8xu  
end 2b2/jzO}J  
%Soft Source- adds a value on the grid ^xFZ;Yf  
pulse = sin(2*pi*frequency*delta_t*n); @*!8  
E(place_pulse) = E(place_pulse) + pulse; ]M#_o]  
%ABC E FL-sXg  
E(1) = E_low_m2; /JJU-A(  
E_low_m2 = E_low_m1; PY~cu@'k{  
E_low_m1 = E(2); bfhap(F~(e  
E(max_space) = E_high_m2; |h4aJv  
E_high_m2 = E_high_m1;  {|a=  
E_high_m1 = E(max_space-1); UhXZ^k3  
for j = 1:max_space-1 EN'}+E 8  
    H(j) = H(j) +eta*(E(j)-E(j+1)); |cUTP!iy  
end +O2T%  
plot(E) ?u/RQ 1  
title('Soft Source Simulation with Dielectric Constant = 4') ZxLgV$U  
axis([0 max_space -1.2 1.2]) (w`9*1NO  
drawnow XhhV7J_F  
end Z2!O)
8  
rK7m(  
FDTD_2.1 ^1nQDd*  
-lAX-W0  
AQ7w5}g+V  
delta_x = .01;%Set the cell size to 1cm OLg=kF[[  
delta_t = delta_x/(2*3e8);%Calculate the time step ^U)xQD"  
max_time = 500; %time is not be limited EPkmBru ^  
max_space = 200; ef*V
s  
E = zeros(max_space,1); %Electric array h0_od/D1r  
H = E; %Magnetic array PS7ta?V QC  
D = E; %flux density array ^Q0%_V,  
I = E; fq-e2MCX5  
dielectric_begin = 100; iK%%  
dielectric_end = 200; kLtm_  
dielectic_space_a = ones(max_space,1); * `1W})  
dielectic_space_b = ones(max_space,1); OXAr..  
eta = 0.5; .?|pv}V  
dielectric_constant = 4; /
?C}PM  
%Lossy Medium variables - for non-Lossy medium set sigma = 0; AXFQ
d@#  
sigma = 0.04; dTcrJ|/Y  
epszero = 8.85419e-12; V $Y=JK@  
etaeps = (delta_t*sigma) / epszero; W:VRLT>w>  
%Initalize ABC conditions ]jQj/`v1  
E_low_m2 = 0; X+dLk(jI`u  
E_low_m1 = 0; '~{bq'7`m  
E_high_m2 = 0; V'alzw7#  
E_high_m1 = 0; l/ufu[x!a  
%Initialize Pulse Variables U|yXJ.Z3  
frequency = 700*1e6;% Unit of Mhz (]ToBju  
place_pulse = 5; }JPLhr|d^  
%Dielectric Medium - wave velocity slows as it travels through the medium &![3{G"+>l  
for i = 1:max_space =cz^g^
7  
if ( i >= dielectric_begin & i <= dielectric_end )  'ONCz  
dielectric_space_a(i) = 1/(dielectric_constant+etaeps); bYt[/K,  
dielectric_space_b(i) = etaeps; `-yo-59E[  
else hc#Sy:T>  
dielectric_space_a(i)=1; tr?U/YG  
dielectric_space_b(i)=0; 
b%A+k"d  
end pg0Sq9qCN  
end EIdEXAC(  
%Main Loop 'ip2|UG  
for n = 1:max_time rlMahY"C  
%Loop for D_x VO u/9]a  
for k = 2:max_space VCf/EkC  
D(k) = D(k)+0.5*(H(k-1)-H(k)); [0>I6Jl  
end m!#'4  
%Soft Source- adds a value on the grid w&F.LiX^  
pulse = sin(2*pi*frequency*delta_t*n); p#;I4d G  
D(place_pulse) = D(place_pulse)+pulse; {$AwG#kt  
%Loop for E_x m-u3^\'  
for k = 1:max_space-1 j3=%J5<  
E(k) = dielectric_space_a(i)*(D(k)-I(k));  4>R)2g  
I(k) = I(k)+dielectric_space_b(i)*E(k); -}x( MZ  
end VPi*9(LS  
%ABC E 9@3cz_[J  
E(1) = E_low_m2; IEmjWw4  
E_low_m2 = E_low_m1; cZR9rnZT  
E_low_m1 = E(2); i U"2uLgb  
E(max_space) = E_high_m2; }e
bu@)r  
E_high_m2 = E_high_m1; >}H3V]  
E_high_m1 = E(max_space-1); Gg TrIF  
%Loop for H_y $ VTk0J-W  
for j = 1:max_space-1 JfLoGl;pm  
H(j) = H(j) +eta*(E(j)-E(j+1)); z{m%^,Cs,  
end Qo\+FkhYq  
plot(E) +d!"Zy2|B  
title('Soft Source Simulation with Dielectric Constant = 4') _jWGwO  
axis([0 max_space -1.2 1.2]) )=TS)C4  
drawnow *e,GXU@  
end

程序代码已经贴在上面了，哪位大侠帮忙看下，这两个程序计算相同的东西为何输出结果却不一样，Sullivan 书上说两个结果应该一样才对呀

好像两叠加系数不一样吧？

什么结果不一样？输出的E波形吗？ I'>r  
我看源一个是加到E上的，一个是加到D上的，源不一样，出来的电场波形当然有点区别了，但频谱分析下来应该结果是一样的。

输出的E波形不一样，如果要使得输出的E波形一样，我该怎么修改FDTD_2.1这个程序呢

去掉 m}oqs0xx  
g!*5@k|C  
%Soft Source- adds a value on the grid 7Fd`MTo  
pulse = sin(2*pi*frequency*delta_t*n); WXzSf.8p|  
D(place_pulse) = D(place_pulse)+pulse; ?cRGdLP'D  
4' MmT'  
%ABC E 前面加上 ~R!M.gY[rK  
%Soft Source- adds a value on the grid IVblSiFF  
pulse = sin(2*pi*frequency*delta_t*n); iF#|Z$g-(  
E(place_pulse) = E(place_pulse) + pulse; ]/klKqz  
mtunD;_Dek  
试一下看看。

刚试过，输出的E波形还是不对

哦，不知道我Matlab删掉没，没删的话，下班后回去看一下。