sa_fig4_32.m

Smart antennas for wireless communication - With MATLAB (Gross F.B. - 2005 - McGraw-Hill)

%Fixed sidelobe cancelling array
d=.5;
N=3
theta=-pi/2:.01:pi/2;
ang=theta*180/pi;
thd=0;
th1=-pi/4;
th2=pi/3;
ind=-1:1;
a1=exp(1j*ind*pi*d*sin(thd));
a2=exp(1j*ind*pi*d*sin(th1));
a3=exp(1j*ind*pi*d*sin(th2));
A=[a1;a2;a3];
%A=[exp(-1j*pi*d*sin(thd)) 1 exp(1j*pi*d*sin(thd));exp(-1j*pi*d*sin(th1)) 1 exp(1j*pi*d*sin(th1));exp(-1j*pi*d*sin(th2)) 1 exp(1j*pi*d*sin(th2))];
w=inv(A)*[1;0;0]
%w=[.748+1j*.094 -.496 .748-1j*.094];
figure;
AF=w(1)*exp(-1j*pi*d*sin(theta))+w(2)+w(3)*exp(1j*pi*d*sin(theta));
figure;plot(ang,abs(AF),'k')
axis([-90 90 0 1.5])
 set(gca,'xTick',[-90:15:90])
xlabel('\theta')
ylabel('|AF|')
grid on
maxx=max(abs(AF));
AFm=abs(AF)/maxx;
figure;
polarpattern(theta,AFm)