对称阵子天线matlab

方向图
clear
lamda=10;%自由空间的波长
n=1.125;
l=n*lamda;
k=2*pi/lamda;%自由空间的相移常数
theta0=[0.0001:0.1:360];
theta=theta0*pi/180;
for i=1:length(theta0)
fe(i)=abs((cos(k*l*cos(theta(i)))-cos(k*l))/sin(theta(i)));
% fh(i)=1-cos(k*l);
end
% figure
polar(theta,fe/max(fe));
xlabel('l=1.125λ');
% figure
% polar(theta,fh/max(fh));
辐射阻抗
clear
lamda=10;%自由空间的波长
n=0.1:0.01:0.9;
l=n*lamda;
k=2*pi/lamda;%自由空间的相移常数
gama=0.5772156;
for i=1:length(n)
Rr1(i)=sin(2*k*l(i))*(Si(4*k*l(i))-2*Si(2*k*l(i)));
Rr2(i)=cos(2*k*l(i))*(gama+log(k*l(i))+Ci(4*k*l(i))-2*Ci(2*k*l(i)));
Rr3(i)=2*(gama+log(2*k*l(i))-Ci(2*k));
Rr(i)=(Rr1(i)+Rr2(i)+Rr3(i))*30;
end
plot(n,Rr)
阻抗特性
clc
clear
lamda=100;%自由空间的波长
n=0.1:0.01:0.9;
l=n*lamda;
a=[30,300,3000];%l和a的比值
k=2*pi/lamda;%自由空间的相移常数
gama=0.5772156;
for j=1:length(a)
for i=1:length(n)
Rr1(i)=sin(2*k*l(i))*(Si(4*k*l(i))-2*Si(2*k*l(i)));
Rr2(i)=cos(2*k*l(i))*(gama+log(k*l(i))+Ci(4*k*l(i))-2*Ci(2*k*l(i)));
Rr3(i)=2*(gama+log(2*k*l(i))-Ci(2*k));
Rr(i)=(Rr1(i)+Rr2(i)+Rr3(i))*30;
Xr1(i)=2*Si(2*k*l(i));
Xr2(i)=sin(2*k*l(i))*(gama+log(k*l(i))+Ci(4*k*l(i))-2*Ci(2*k*l(i))-2*log(a(j)));
Xr3(i)=cos(2*k*l(i))*(2*Si(2*k*l(i))-Si(4*k*l(i)));
Xr(i,j)=(Xr1(i)+Xr2(i)+Xr3(i))*30;
Zca(i)=120*(log(2*(a(j)))-1);
afa(i)=Rr(i)/(Zca(i)*l(i)*(1-sin(2*k*l(i))/(2*k*l(i))));
Rin(i,j)=Zca(i)*(sinh(2*afa(i)*l(i))-afa(i)/k*sin(2*k*l(i)))/(cosh(2*afa(i)*l(i))-cos(2* k*l(i)));
Xin(i,j)=-Zca(i)*(afa(i)/k*sinh(2*afa(i)*l(i))+sin(2*k*l(i)))/(cosh(2*afa(i)*l(i))-cos(2 *k*l(i)));
end
end
figure
plot(n,Rr)%辐射电阻
title('辐射电阻随l/λ的变化曲线');
xlabel('l/λ');
ylabel('Rr (Ω)');
figure
plot(n,Xr)%辐射电抗
title('l/a不同时辐射电抗随l/λ的变化曲线');
xlabel('l/λ');
ylabel('Xr (Ω)');
figure
plot(n,Rin)%输入电阻
title('不同平均特性阻抗时输入电阻随l/λ的变化曲线');
xlabel('l/λ');
ylabel('Rin (Ω)');
figure
plot(n,Xin)%输入电抗
title('不同平均特性阻抗时电抗随l/λ的变化曲线');
xlabel('l/λ');
ylabel('Xin (Ω)');
对称阵子
clc
clear
lamda=10;%自由空间的波长
n=0.25;
l=n*lamda;
k=2*pi/lamda;%自由空间的相移常数
theta0=[0.0001:0.1:360];
theta=theta0*pi/180;
for i=1:length(theta0)
fe(i)=abs((cos(k*l*cos(theta(i)))-cos(k*l))/sin(theta(i)));
fh(i)=1-cos(k*l);
end
figure
polar(theta,fe/max(fe));
figure
polar(theta,fh);
用MATLAB语言编程计算半波对称振子场图，电流分布和输入阻抗n=2*pi;
d=n/50+0.001;
[x,y] = meshgrid(-n:d:n,-n:d:n);
nn=30
j=0;
M = moviein(nn);
for j=1:nn
z=(x./sqrt(x.^2+y.^2)).^2.*(...
-sin(sqrt(x.^2+y.^2)-j*2*pi/nn)...
-cos(sqrt(x.^2+y.^2)-j*2*pi/nn)./sqrt(x.^2+y.^2)...
);
v=[-1 -0.9 -0.8 -0.75 -0.5 -0.25 -0.1 -0.05 0 0.05 0.1 0.25 0.5 ...
0.75 0.8 0.9 1];
%v=[ -0.75 -0.5 -0.25 0 0.25 0.5 0.75 ];
contour(z,v);
%contour(z,30);
%colorbar
axis equal
%grid on
M(:,j) = getframe;
end
movie(M,100,10)
clear all
N = 10;
d = 0.5;
alpha = 2*pi;
dip=[1:N];
kd=2*pi*d;
phi=[0:2*pi/800.1:2*pi];
framemax = 48;
M = moviein(framemax);
set(gcf,'Position',[100 100 640 480])
for n=1:framemax
u=kd*cos(phi)-alpha/framemax*(n-1);
F=abs(sin(N.*u./2+N*1e-15)./sin(u./2+1e-15));
plot(F.*cos(phi),F.*sin(phi),'r','LineWidth',3);
%polar(phi,abs(F));
title([ num2str(N),' elements, '...
,num2str(d),' \lambda apart'],'fontsize', 18)
xlabel(['\alpha=' ,num2str(alpha/framemax*(n-1))],'Color','k','fontsize', 18) hold on
plot(N.*cos(phi),N.*sin(phi),'b','LineWidth',2);
plot(dip-N/2-0.5,dip*0,'o','linewidth',3)
hold off
axis equal
M(:,n) = getframe(gcf);
end
clf reset
set(gcf,'Position',[100 100 800 600])
axis off
movie(M,1,6)
clear all
N = 10;
d = 0.5;
alpha = 2*pi;
dip=[1:N];
kd=2*pi*d;
phi=[0:2*pi/800.1:2*pi];
framemax = 48;
M = moviein(framemax);
set(gcf,'Position',[100 100 640 480])
for n=1:framemax
u=kd*cos(phi)-alpha/framemax*(n-1);
F=abs(sin(N.*u./2+N*1e-15)./sin(u./2+1e-15));
plot(F.*cos(phi),F.*sin(phi),'r','LineWidth',3);
%polar(phi,abs(F));
title([ num2str(N),' elements, '...
,num2str(d),' \lambda apart'],'fontsize', 18)
xlabel(['\alpha=' ,num2str(alpha/framemax*(n-1))],'Color','k','fontsize', 18) hold on
plot(N.*cos(phi),N.*sin(phi),'b','LineWidth',2);
plot(dip-N/2-0.5,dip*0,'o','linewidth',3)
hold off
axis equal
M(:,n) = getframe(gcf);
end
clf reset
set(gcf,'Position',[100 100 800 600])
axis off
movie(M,1,6)
clear;clc;
range=1/4;
point=6;
wave_length_value=1;
measurement=7.022*(10)^(-3);
v0=1;
k=(2*pi)/wave_length_value;
a=measurement*wave_length_value;
l=range*wave_length_value;
step=l/(point-1);
i_point=1:point; % 测试点赋值
matrix_wavelength(i_point)=step*(i_point-1);
z=linspace(-l,l,100); % 积分离散
for i_point=1:point; % 求解A向量
r=((matrix_wavelength(i_point)-z).^2 + a^2).^(1/2); % 场源距离离散
g=exp(-j*k*r)./r; % 格林函数离散
A(i_point)=trapz(z,sin(k*(1/4-abs(z))).*g); % A元素确定
end
for i_point=1:point; % 求解B向量
r=((matrix_wavelength(i_point)-z).^2 + a^2).^(1/2); % 场源距离离散
g=exp(-j*k*r)./r; % 格林函数离散
B(i_point)=trapz(z,sin(2*k*(1/4-abs(z))).*g); % B元素确定
end
for i_point=1:point; % 求解C向量
r=((matrix_wavelength(i_point)-z).^2 + a^2).^(1/2); % 场源距离离散
g=exp(-j*k*r)./r; % 格林函数离散
C(i_point)=trapz(z,sin(3*k*(1/4-abs(z))).*g); % B元素确定
end
for i_point=1:point; % 求解D向量
r=((matrix_wavelength(i_point)-z).^2 + a^2).^(1/2); % 场源距离离散
g=exp(-j*k*r)./r; % 格林函数离散
D(i_point)=trapz(z,sin(4*k*(1/4-abs(z))).*g); % B元素确定
end
for i_point=1:point; % 求解E向量
r=((matrix_wavelength(i_point)-z).^2 + a^2).^(1/2); % 场源距离离散
g=exp(-j*k*r)./r; % 格林函数离散
E(i_point)=trapz(z,sin(5*k*(1/4-abs(z))).*g); % B元素确定
end
for i_point=1:point; % 求解F向量
F(i_point)=cos(k*matrix_wavelength(i_point)); % B元素确定
end
impedance_matrix=[A.',B.',C.',D.',E.',F.']; % 阻抗矩阵确定
for i_point=1:point; % 电压矩阵确定
voltage_matrix(i_point)=(-j*v0/60)*sin(k*abs(matrix_wavelength(i_point))); % B元素确定
end
% 求解a1,a2,a3,a4,a5,C_contant;
current=impedance_matrix\voltage_matrix';
z_distribute=linspace(0,l,100); % 图形表示
current_function=current(1,1)*sin(k*(l-abs(z_distribute)))
+current(2,1)*sin(2*k*(l-abs(z_distribute)))+current(3,1)*sin
(3*k*(l-abs(z_distribute)))+current(4,1)*sin(4*k*(l-abs(z_distribute)))+current(5,1)*s in(5*k*(l-abs(z_distribute)));
current_re=real(current_function); % 电流实虚部
current_im=imag(current_function);
plot(current_re,z_distribute,'r'); % 绘图
hold on;
plot(current_im,z_distribute,'g');
xlabel('current distribution');
ylabel('unitary distance')
title('antenna current distribution plot'); legend('real current','imag current',2);。