利用ZMNL方法进行雷达杂波的仿真与模拟，生成具有瑞利分布的杂波.zip

？%%%%瑞利杂波的产生过程clear all;close allazi_num=2000; %雷达回波帧数,一帧表示一个重复周期 fr=1000; lamda0=0.05; sigmav=1.0; sigmaf=2*sigmav/lamda0; randn('state',sum(100*clock)); d1=randn(1,azi_num); rand('state',7*sum(100*clock) 3); d2=randn(1,azi_num); xi=2*sqrt(-2*log(d1)).*cos(2*pi*d2); xq=2*sqrt(-2*log(d1)).*cos(2*pi*d2); coe_num=12; %用傅里叶级数展开法求滤波器系数？？？ for n=0:coe_num; coeff(n 1)=2*sigmaf*sqrt(pi)*exp(-4*sigmaf^2*pi^2*n^2/fr^2)/fr; end for n=1:2*coe_num 1 if n<=coe_num 1 b(n)=1/2*coeff(coe_num 2-n); else b(n)=1/2*coeff(n-coe_num); end end %%%生成高斯谱杂波 xxi=conv(b,xi); xxq=conv(b,xq); xxi=xxi(coe_num*2 1:azi_num coe_num*2); xxq=xxq(coe_num*2 1:azi_num coe_num*2); xisigmac=std(xxi); ximuc=mean(xxi); yyi=(xxi-ximuc)/xisigmac; xqsigmac=std(xxq); xqmuc=mean(xxq) yyq=(xxq-xqmuc)/xqsigmac; sigmac=1.2; yyi=sigmac*yyi; yyq=sigmac*yyq;% j=sqrt(-1); ydata=yyi j*yyq; figure(2), subplot(2,1,1),plot(real(ydata)); title('瑞利杂波时域波形--实部') subplot(2,1,2),plot(imag(ydata)); title('瑞利杂波时域波形--虚部') num=100; maxdat=max(abs(ydata)); mindat=min(abs(ydata)); NN=hist(abs(ydata),num); xpdf1=num*NN/((sum(NN))*(maxdat-mindat)); xaxis1=mindat:(maxdat-mindat)/num:maxdat-(maxdat-mindat)/num; th_va1=(xaxis1./sigmac^2).*exp(-xaxis1.^2./(2*sigmac^2)); figure(3), plot(xaxis1,xpdf1); hold ;plot(xaxis1,th_va1,':r'); title('杂波的幅度分布'); xlabel('杂波的幅度') ylabel('概率密度') signal=ydata; signal=signal-mean(signal); %%%%用burg法来估计功率谱密度 figure(4), M=256; psd_dat=pburg(real(signal),32,M,fr); psd_dat=psd_dat/(max(psd_dat)); freqx=0:0.5*M; freqx=freqx*fr/M; plot(freqx,psd_dat); title('杂波频谱'); xlabel('频率/Hz') ylabel('功率谱密度') %%%作出理想的功率谱曲线 powerf=exp(-freqx.^2/(2*sigmaf.^2)); hold plot(freqx,powerf,':r');