قلم

کد زیر برای تطبیق امپدانسی با استفاده از استاب موازی و سری برای حالت های اتصال کوتاه و مدار باز استفاده می شود .

% AmirHosein HajiHoseini

close all

clear

clc

disp('menu')

disp('1 - paralell stubs')

disp('2 - sery stubs')

q=input('select 1 or 2 \n');

z=input('please enter Zl :');

zl=z/50 ; % normalaizing Zl

 

%% Draw outer circle

t = linspace(0, 2*pi, 100);

x = cos(t);

y = sin(t);

plot(x, y); axis equal;

 

% Place title and remove ticks from axes

title(' Smith Chart ')

set(gca,'xticklabel',{[]});

set(gca,'yticklabel',{[]});

hold on

 

% ??? ????? ??? real

k = 0:0.1:1;%k=r/(1-r);r=real(zl)

for j = 1 : length(k)

    x(j,:) = +k(j)+ (1 - k(j)) * cos(t);

    y(j,:) = +(1 - k(j)) * sin(t);

    plot(x(j,:), y(j,:), 'k')

end

 

% ??? ????? ??? image

kt=pi/2:pi/10:2*pi;%???? ????? ????? ???? ?????? ??? image

for j=1: length(kt)

k(j) = (-cos(kt(j)))/(sin(kt(j))+1);%k=1/x;x=image(zl)

end

 

for j = 1 : length(kt)

    t = linspace(kt(j), 1.5*pi, 50);

    a(j,:) = +1 + k(j) * cos(t);

    b(j,:) = +k(j) + k(j) * sin(t);

    plot(a(j,:), b(j,:),'k:', a(j,:), -b(j,:),'k:' )

end

%% calculations for paralell stubs

if q==1

% plotting circle of Zl

    g=(zl-1)./(zl+1);%?????? ????

    g1=abs(g);

    t = linspace(0, 2*pi, 100);

    c = g1.*cos(t);

    d = g1.*sin(t);

    plot(c, d,'r','LineWidth',2); axis equal; % ??? ????? ?? ????zl

%plot circlr g=1

    e = 0.5+ (1 - 0.5) * cos(t);

    f = 0.5 * sin(t);

    plot(e, f, 'c','LineWidth',2)

% calculating d

    p1=g1^2+1i.*(g1*sqrt(1-g1^2));%???? ????? ????? g=1 ? ????? ?? ????zl

    p2=g1^2+1i.*-g1*sqrt(1-g1^2);

    d1=abs(angle(p1)-angle(zl))/(4*pi);

    disp('d1/landa =')

    disp(d1)

    d2=abs(angle(p2)-angle(zl))/(4*pi);

    disp('d2/landa =')

    disp(d2)

% calculating L

    disp('for s.c stub the answers are :')

    m=(1i)/(g1*sqrt(1-g1^2));%convert p1 to admitance

    p5=(m-1)./(m+1);

    l1=abs(angle(p5)-pi)/(4*pi);

    disp('L1/landa=')

    disp(l1)

    n=(1i)/(-g1*sqrt(1-g1^2));%convert p2 to admitance

    p6=(n-1)./(n+1);

    l2=abs(angle(p6)-pi)/(4*pi);

    disp('L2/landa=')

    disp(l2)

    disp('for o.c stub the answers are :')

    l3=l1+0.25;

    l4=l2+0.25;

    disp('L3/landa=')

    disp(l3)

    disp('L4/landa=')

    disp(l4)

    p3=-p1;

    p4=-p2;

%% plotting

plot(real(g),imag(g), 'b.', 'markersize',18);

plot(real(p1),imag(p1), 'b.', 'markersize',18);

plot(real(p2),imag(p2), 'b.', 'markersize',18);

plot(real(p3),imag(p3), 'b.', 'markersize',18);

plot(real(p4),imag(p4), 'b.', 'markersize',18);

plot(real(p5),imag(p5), 'b.', 'markersize',18);

plot(real(p6),imag(p6), 'b.', 'markersize',18);

plot([0 real(g)],[0 imag(g)],'m','LineWidth',2)

plot([real(p1) real(p3)],[imag(p1) imag(p3)],'k','LineWidth',3)

plot([real(p2) real(p4)],[imag(p2) imag(p4)],'b','LineWidth',3)

plot([0 real(p5)],[0 imag(p5)],'g','LineWidth',2)

plot([0 real(p6)],[0 imag(p6)],'g','LineWidth',2)

end

 

%% calculations for sery stubs

if q==2

% plotting circle of Zl

    g=(zl-1)./(zl+1);

    g1=abs(g);

    t = linspace(0, 2*pi, 100);

    c = g1.*cos(t);

    d = g1.*sin(t);

    plot(c, d,'r','LineWidth',2); axis equal;

%plot circlr g=1

    e = 0.5+ (1 - 0.5) * cos(t);

    f = 0.5 * sin(t);

    plot(e, f, 'c','LineWidth',2)

% calculating d

    p1=g1^2+1i.*(g1*sqrt(1-g1^2));

    p2=g1^2+1i.*-g1*sqrt(1-g1^2);

    d1=abs(angle(p1)-angle(zl))/(4*pi);

    disp('d1/landa =')

    disp(d1)

    d2=abs(angle(p2)-angle(zl))/(4*pi);

    disp('d2/landa =')

    disp(d2)

% calculating L

    disp('for s.c stub the answers are :')

    m=imag(p2);

    %????? ???? ????? ??????

    p5=(-1i*m-1)./(-1i*m+1);

    l1=abs(angle(p5)-pi)/(4*pi);

    disp('L1/landa=')

    disp(l1)

    n=-m;

    %????? ???? ????? ??????

    p6=(-1i*n-1)./(-1i*n+1);

    l2=abs(angle(p6)-pi)/(4*pi);

    disp('L2/landa=')

    disp(l2)

    disp('for o.c stub the answers are :')

    l3=l1+0.25;

    l4=l2+0.25;

    disp('L3/landa=')

    disp(l3)

    disp('L4/landa=')

    disp(l4)

 

%% plotting

plot(real(g),imag(g), 'b.', 'markersize',18);

plot(real(p1),imag(p1), 'b.', 'markersize',18);

plot(real(p2),imag(p2), 'b.', 'markersize',18);

plot(real(p5),imag(p5), 'b.', 'markersize',18);

plot(real(p6),imag(p6), 'b.', 'markersize',18);

plot([0 real(g)],[0 imag(g)],'m','LineWidth',2)

plot([real(p1) 0],[imag(p1) 0],'k','LineWidth',3)

plot([real(p2) 0],[imag(p2) 0],'b','LineWidth',3)

plot([0 real(p5)],[0 imag(p5)],'g','LineWidth',2)

plot([0 real(p6)],[0 imag(p6)],'g','LineWidth',2)

end