clear all;
close all;
clc;
N=8;
zpb=13.5;
c=1500;
f0=1500;
fs=5000;
nfft=512;
A=2;
d=0.4;
n=1:nfft;
w=2*pi*f0;
s=zeros(N,nfft);
y=[];
for x=-pi/2:pi/180:pi/2
    tao=d*(sin(x)-sin(0))/c;
   for i=1:N
        s(i,:)=A*cos(w*(n/fs+tao*(i-1)));
    end
     p=sum(s);
b =sqrt(sum(p.^2));
y=[y,b];
end
y=y/max(y);
x=-pi/2:pi/180:pi/2;
plot(x*180/pi,20*log10(y));
title('線陣自然指向性');
xlabel('入射信號角度');
ylabel('幅度響應(dB)');
axis([-95 95 -60 10]);
grid on;