music_bf_capon.m

谱估计源程序：是谱估计中的经典算法esprit,MUSIC等算法的源程序

clear all; close all;clc;
%classical high resolution DOA estimation algorithm
%including Bartlett beamforming algorithm;Capon algorithm;Esprit;
%MUSIC; WSF; etc;
clear all; close all;clc;
J=sqrt(-1);
source_number=2;
source_doa=[40 70 ];
sensor_number=8;
snapshot_number=100;
snr=10;
 
A=exp(-J*(0:sensor_number-1)'*pi*sin(source_doa*pi/180));
s=(randn(source_number,snapshot_number)+J*randn(source_number,snapshot_number))/sqrt(2);
x=A*s;
y=awgn(x,snr);
 
R=y*y'/snapshot_number;
 
[V,D]=eig(R);
Un=V(:,1:sensor_number-source_number);
Gn=Un*Un';
 

searching_doa=0:0.1:90;
for i=1:length(searching_doa)
    a_theta=exp(-J*(0:sensor_number-1)'*pi*sin(pi*searching_doa(i)/180));
    P_BF(i)=abs((a_theta'*R*a_theta)./(a_theta'*a_theta));
    P_capon(i)=1./abs((a_theta'*inv(R)*a_theta));
    P_music(i)=1./abs((a_theta'*Gn*a_theta));
end
figure(1);
plot(searching_doa,P_BF);
legend('Bartlett spectrum');
 figure(2);
plot(searching_doa,P_capon);
legend('Capon spectrum');
figure(3);
plot(searching_doa,P_music);
 
legend('Music spectrum');