光纖中超連續(xù)譜的產(chǎn)生代碼

1、%主程序等人代碼%代碼基于J.C.Travers,M.HFroszandJ.M.Dudley進行修改以及優(yōu)化cputime=0;tic;n=2A13;%精度twidth=12.5e-12;%時間窗口c=299792458;%光速wavelength=535e-9;%入射波長w0=(2*pi*c)/wavelength;dt=twidth/n;T=(-n/2:n/2-1).*dt;%=輸入脈沖參數(shù)power=10000;%輸入脈沖功率t0=28.4e-15;%脈寬A=sqrt(power)*sech(T/t0);%場flength=0.15;betas=-1.1830e-026,8.1038e-

2、041,-9.5205e-056,2.0737e-070,.-5.3943e-085,1.3486e-099,-2.5495e-114,3.0524e-129,.-1.7140e-144;gamma=0.11;loss=0;%=拉曼響應計算(石英光纖中)fr=0.18;tau1=0.0122e-12;tau2=0.032e-12;RT=(tau1A2+tau2A2)/tau1/tau2A2*exp(-T/tau2).*sin(T/tau1);RT(T<0)=0;%=模擬使用參數(shù)nsaves=200;%步長Z,AT,AW,W=gnlse1(T,A,w0,gamma,betas,loss,.

3、fr,RT,flength,nsaves);%=輸出繪圖figure(1);WL=2*pi*c./W;iis=(WL>450e-9&WL<1650e-9);lIW=10*log10(abs(AW).A2.*2*pi*c./WL'.A2);mlIW=max(max(lIW);subplot(1,2,1);pcolor(WL(iis).*1e9,Z,lIW(:,iis);caxis(mlIW-40.0,mlIW);xlim(450,1650);shadinginterp;xlabel('Wavelength/nm');ylabel('Distan

4、ce/m');lIT=10*log10(abs(AT)A2);mlIT=max(max(lIT);subplot(1,2,2);pcolor(T.*1e12,Z,lIT);caxis(mlIT-40.0,mlIT);xlim(-0.5,6);shadinginterp;xlabel('Delay/ps');ylabel('Distance/m');figure(2)lIW1=lIW(200,:);WL1=(WL.*1e9)'lIW2=lIW(134,:);lIW3=lIW(67,:);lIW4=lIW(27,:);lIW5=lIW(14,:);l

5、IW6=lIW(7,:);lIW7=lIW(1,:);subplot(7,2,1);plot(WL1(iis),lIW1(1,iis);set(gca,'box');ylabel('15cm');subplot(7,2,3);plot(WL1(iis),lIW2(1,iis);set(gca,'box');ylabel('10cm');subplot(7,2,5);plot(WL1(iis),lIW3(1,iis);set(gca,'box');ylabel('5cm');subplot(7,2,7

6、);plot(WL1(iis),lIW4(1,iis);set(gca,'box');ylabel('2cm');subplot(7,2,9);plot(WL1(iis),lIW5(1,iis);set(gca,'box');ylabel('1cm');subplot(7,2,11);plot(WL1(iis),lIW6(1,iis);set(gca,'box');ylabel('0.5cm');subplot(7,2,13);plot(WL1(iis),lIW7(1,iis);set(gca,&#

7、39;box'nm');ylabel('0cm');toc;,'on');set(gca,'on');set(gca,'on');set(gca,'on');set(gca,'on');set(gca,'on');set(gca,'on');xlabel('xticklabel''xticklabel''xticklabel''xticklabel''xticklabel'

8、'xticklabel''Wavelength/,cputime=toc;%顯示用時%GNLSE方程編寫functionZ,AT,AW,W=gnlse(T,A,w0,gamma,betas,.loss,fr,RT,flength,nsaves)n=length(T);dT=T(2)-T(1);V=2*pi*(-n/2:n/2-1)'/(n*dT);alpha=log(10.A(loss/10);B=0;fori=1:length(betas)B=B+betas(i)/factorial(i+1).*V.A(i+1);endL=1i*B-alpha/2;%線性算子

9、ifabs(w0)>epsgamma=gamma/w0;W=V+w0;elseW=1;endRW=n*ifft(fftshift(RT.');L=fftshift(L);W=fftshift(W);functionR=rhs(z,AW)AT=fft(AW.*exp(L*z);IT=abs(AT).A2;if(length(RT)=1)|(abs(fr)<eps)M=ifft(AT.*IT);elseRS=dT*fr*fft(ifft(IT).*RW);M=ifft(AT.*(1-fr).*IT+RS);endR1=exp(-L*(z/2);R2=R1.*1i*gamma.*

10、W.*M;R=R2.*exp(-L*(z/2);%對稱分布傅里葉思想：對于足夠短的傳輸距離h，在h/2的距離內，只考慮色散的作用，得到A(z+h/2,T)。然后利用A(z+h,T)求非線性算符，再考慮+h范圍內非線性作用。最后考慮剩下h/2段的色散作用。上述過程完成了從z至收+h的傳輸%=%,z/flength*100);functionstatus=report(z,y,flag)status=0;ifisempty(flag)fprintf('%05.1f%completen'endendZ=linspace(0,flength,nsaves);'AbsTol',1e-12,options=odeset('RelTol',1e-5,'NormControl','on',.'OutputFcn',report);Z,AW=ode45(rhs,Z,if