二维波导传播常数计算

二维波导传播常数计算（MatLab语言）%a*b%时间步数与频率点数%a*b%时间步数与频率点数%fieldsarrayfor%取样时刻%?%步长%时间步长%带通源计算clearc=2.9979E8;u0=1.256637E-6;e0=8.84194185E-12;a=7.112e-3;b=3.556e-3;nt=7500;nf=300;nx1=21;ny1=41;Transversesectionnt1=500;nt2=1000;nt3=5500;pi2=pi*2;pia=pi/a;dpaj=-j*pi2;nx=nx1-1;ny=ny1-1;js=ny/2+7;jc=5;ic=nx1-4;dx=b/nx;dy=a/ny;sbeta=0dt=0.99/c/sqrt(l/dx^2+l/dy.A2);dtuy=dt/(u0*dy);dtuz=dt/(u0);dtex=dt/(e0*dx);dtey=dt/(e0*dy);dtez=dt/(e0);dtux=dt/(u0*dx);%FDTD计算中参量计算ex=zeros(nxl,nyl);ey=zeros(nxl,nyl);ez=zeros(nxl,nyl); hx=zeros(nxl,nyl);hy=zeros(nx1,ny1);hz=zeros(nx1,ny1);%场量初始化io=ll;jo=24; %取样点%dataforexcitingsourcestt=1.5e3; %?to=dt*stt;fo=pi2*33.25e9;df=pi2*15.75e9;aa=1e-8;t=0;fv1(1:nf)=0;%ftdtbeganfork=1:nttt=t-to;ct=fo*tt;iftt==0fcc=aa*df/pi;elsest=df*tt;fcc=aa*sin(st)*cos(ct)/(pi*tt);endt=t+dt;if(k/3)>(2*stt)fcc=0;end%%%%%%%%%%%FDTD子程序fori=2:nxforj=1:nyhx(i,j)=hx(i,j)+dtuz*sbeta*ey(i,j)-dtuy*(ez(i,j+1)-ez(i,j));endendforj=1:nyhx(1,j)=0;hx(nx1,j)=0;endfori=1:nxforj=2:nyhy(i,j)=hy(i,j)+dtux*(ez(i+1,j)-ez(i,j))-dtuz*sbeta*ex(i,j);endendfori=1:nxhy(i,1)=0;hy(i,ny1)=0;endfori=1:nxforj=1:nyhz(i,j)=hz(i,j)+dtuy*(ex(i,j+1)-ex(i,j))-dtux*(ey(i+1,j)-ey(i,j));endendfori=1:nxforj=2:nyifj==jsex(i,j)=ex(i,j)+dtey*(hz(i,j)-hz(i,j-1))+dtez*sbeta*hy(i,j)+fcc;elseex(i,j)=ex(i,j)+dtey*(hz(i,j)-hz(i,j-1))+dtez*sbeta*hy(i,j);endendendfori=1,nxex(i,1)=0;ex(i,ny1)=0;endfori=2:nxex(i,1)=0;ex(i,ny1)=0;endfori=2:nxforj=1:nyey(i,j)=ey(i,j)-dtez*sbeta*hx(i,j)-dtex*(hz(i,j)-hz(i-1,j));

endendforj=1:nyey(1,j)=0;ey(nx1,j)=0;endfori=2:nxforj=2:nyez(i,j)=ez(i,j)+dtex*(hy(i,j)-hy(i-1,j))-dtey*(hx(i,j)-hx(i,j-1));endendfori=1:nx1ez(i,1)=0;ez(i,ny1)=0;endforj=1:ny1ez(1,j)=0;ez(nx1,j)=0;enddomainat11,24domainat11,24tv1(k)=ex(io,jo);%ElectricFieldsRecordsoftimeendfid1=fopen('1','w');%Produceofthedatafilefprintf(fid1,'%g',tv1);fclose(fid1);plot(tv1);%FTSTART%%%DFTbeginpi2jnt=-j*pi2;fo=0e9;%开始频率ff=fo;df=50e9/nf;%步长fork=1:nfff=ff+df;form=1:nt%fv1(k)=fv1(k)+tv1(m)*exp(pi2jnt*m*dt*ff);fv1(k)=fv1(k)+tv1(m)*cos(pi2*m*dt*ff);end

end%%记录ftvl幅值（归一化%%记录ftvl幅值（归一化）figure;fidlf=fopen('2','w');fprintf(fidl