波在匹配介质间的传播

%1D FDTD simulation with a simple absorbing boundary condition
% and a TFSF boundary between hy[49] and ez[50]. 
% dielectric material located ez[100]
SIZE = 400;
LOSS = 0.01;
LOSS_LAYER =250;
ez = zeros(1,SIZE);
hy = zeros(1,SIZE-1);
ceze = zeros(1,SIZE);
cezh = zeros(1,SIZE);
chyh = zeros(1,SIZE-1);
chye = zeros(1,SIZE-1);
imp0=377.0;
maxTime = 10000;
% initialize update coefficient
for mm = 1 : 1 : SIZE -1
    if mm < 100
        ceze(mm) =  1.0;
        cezh(mm) = imp0;
    else if mm < LOSS_LAYER
        ceze(mm) =  1.0;
        cezh(mm) = imp0/9.0;
        else            
       ceze(mm) =  (1-LOSS)/(1+LOSS);
       cezh(mm) = imp0 /9/(1+LOSS);
        end
        
    end
end
for mm = 1 : 1 : SIZE -1
     if mm < LOSS_LAYER
       chyh(mm) = 1.0;
       chye(mm) = 1.0/imp0;
    else
        chyh(mm) = (1-LOSS)/(1+LOSS);
       chye(mm) = 1.0/imp0/(1+LOSS);
        
    end
end
for qTime = 0 : 1 : maxTime
    % hy(SIZE)=hy(SIZE-1);%
    
    % update magnetic field
    for mm = 1 : 1 : SIZE -1
        hy(mm) = hy(mm)*chyh(mm) + (ez(mm+1)- ez(mm))*chye(mm);
    end   
% correction for Hy adjacent to TFSF boundary */
 hy(50)=hy(50)-exp(-(qTime - 30)*(qTime - 30) / 100) / imp0;
 
    figure(1);
    subplot(211);t_hy = plot(hy);    
    title('Magnetic Field');  
    
    % ABC
    ez(1)=ez(2);%   
%      ez(SIZE)=ez(SIZE-1);%

    for mm = 2 : 1 : SIZE-1 
         ez(mm) = ez(mm)*ceze(mm) + (hy(mm)- hy(mm-1))*cezh(mm);
    end    
%     figure(2); 
    subplot(212);
    t_ez = plot(ez);
    title('Electric Field')
    ez(51) = ez(51) + exp(-(qTime+0.5-(-0.5)-30.0)*(qTime+0.5-(-0.5)-30.0)/100.0);
    
%     pause(0.01);
% %     refreshdata(t_hy);
%     refreshdata(t_ez);
%     drawnow;
end