doa_k.m

干涉仪测向具有精度高、速度快的特点

 %%该程序仿真利用干涉技术测向的方法,测试不同分数比的影响
 clear all;
 close all;
 clc;
 result=zeros(1,100);
 for Loop=1:500
 for loop=1:100
 d1=0.58;%%
 d2=(loop+0.0015)*d1;%%可以调整分数比
 k=floor(d2/d1);%%基线的整数倍
 deltak=d2/d1-k;%%基线的小数部分
 f=1e10;%%信号频率
 C=3e8;%光速
 lambda=C/f;%信号波长
 sita0=30;%%入射角
 sita=((sita0)/180)*pi;
 phi1=2*pi*d1*sin(sita)/lambda;
 phi2=2*pi*d2*sin(sita)/lambda;
delta_phi10=mod(phi1,2*pi);
delta_phi20=mod(phi2,2*pi);
sig1=exp(j*phi1)+0.0001*(randn(1)+j*randn(1));
sig2=exp(j*phi2)+0.0001*(randn(1)+j*randn(1));
delta_phi1=mod(angle(sig1),2*pi);
delta_phi2=mod(angle(sig2),2*pi);
c=floor(delta_phi1*(d2/d1)/(2*pi));
% m=n*k+c;
phi=delta_phi2+2*pi*c-delta_phi1*(d2/d1);
if abs(phi)<=1e-5
    phi=0;
end
 if phi>=0
     n=floor((phi/(2*pi*deltak)+0.5));
     m=n*k+c;
 else
     n=floor((phi+2*pi)/(2*pi*deltak)+0.5);
     m=n*k+c+1;
 end
  temp1(loop)=n*deltak;
 answer1(loop)=abs(asin((2*pi*n+delta_phi1)*lambda/(2*pi*d1))/(2*pi)*360);%利用phi1求解
 answer2(loop)=abs(asin((2*pi*m+delta_phi2)*lambda/(2*pi*d2))/(2*pi)*360);%利用phi2求解
 delta_phi=1/2*(delta_phi2+(2*pi*n+delta_phi1)*d2/d1-2*pi*m);%最小二乘解
 answer(loop)=abs(asin((2*pi*m+delta_phi)*lambda/(2*pi*d2))/(2*pi)*360);
end
result=result+(answer-sita0).^2;
Loop
end
result=(result/Loop).^0.5;
figure;plot((10:10:100),result(10:10:100),':*')
 xlabel('不同分数比');
 ylabel('测量误差');