%%---------------beampattern of the phased array--------------------

%%-----------------2023.5.6 Xidian University----------------------

clc; clear all; close all;

% ========================================================================

% parameter setting

% ========================================================================

j = sqrt(-1);

N=10;

c = 3e8;

f0=3e8;

lambda0=c/f0;

d=lambda0/2;

theta_s=0;

% ========================================================================

% data

% ========================================================================

w_non=exp(j*2*pi/lambda0*(0:N-1)'*d*sind(theta_k)); % non-dapvtive weight vector

% ========================================================================

% beamforming

% ========================================================================

theta = (-90:1:90); % scope of the angle

AF = zeros(1,length(theta)); % non-adaptive beampattern (data-independent)

for i = 1:length(theta)

a= exp(j*2*pi/lambda0*(0:N-1)'*d*sind(theta(i)));

AF(i) = w'*a;

end

% ========================================================================

% plot figure

% ========================================================================

AF= 20*log10(abs(AF)/(max((abs(AF)))));

disp_dB = -60;

for i = 1 : length(theta)

if (AF(i) < disp_dB); AF(i) = disp_dB; end

end

plot(theta,AF); % 绘制方向图

axis tight; axis xy;

grid on; hold on;

xlabel('angle(degree)'); ylabel('Normalized voltage amplitude(dB)');

title('non-adaptive beampattern');