Wave Propagation

Question.

            z를 0에서 100m의 구간에서 f = 10MHz 경우에 대해서 t = 0, t = 10nsec, 20nsec일 때의 E(z, t)와

            H(z, t)를 도시해보시오.

clc; clear; close all;

a= 1e2;
f = 10e6;
w = 2*pi*f;
E0 = 1;
e0 = 1e-9/(36*pi);
m0 = 4*pi*1e-7;
k = w*sqrt(m0*e0);
intrin = (w*m0)/k;
H0 = E0/intrin;
 
t1 = 0;
t2 = 10e-9;
t3 = 20e-9;
z = linspace(0, 100, 1e5);
 
E1 = E0*cos(w*t1-k*z);
E2 = E0*cos(w*t2-k*z);
E3 = E0*cos(w*t3-k*z);
 
H1 = H0*cos(w*t1-k*z);
H2 = H0*cos(w*t2-k*z);
H3 = H0*cos(w*t3-k*z);

subplot(2, 1, 1); plot(z, E1, z , E2, z, E3, 'linewidth', 2)
title('E(z, t)');
xlabel('z');
ylabel('E(z, t)');
legend('t=0', 't=10e-9', 't=20e-9');
 
subplot(2, 1, 2); plot(z, H1, z , H2, z, H3, 'linewidth', 2)
title('H(z, t)');
xlabel('z');
ylabel('H(z, t)');
legend('t=0', 't=10e-9', 't=20e-9');

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Question.

            위의 문제에서 f = 30MHz로 변경해서 그 결과를 도시하시오.

clc; clear; close all;

a= 1e2;
f = 30e6;
w = 2*pi*f;
E0 = 1;
e0 = 1e-9/(36*pi);
m0 = 4*pi*1e-7;
k = w*sqrt(m0*e0);
intrin = (w*m0)/k;
H0 = E0/intrin;
 
t1 = 0;
t2 = 10e-9;
t3 = 20e-9;
z = linspace(0, 100, 1e5);
 
E1 = E0*cos(w*t1-k*z);
E2 = E0*cos(w*t2-k*z);
E3 = E0*cos(w*t3-k*z);

H1 = H0*cos(w*t1-k*z);
H2 = H0*cos(w*t2-k*z);
H3 = H0*cos(w*t3-k*z);
 
subplot(2, 1, 1); plot(z, E1, z , E2, z, E3, 'linewidth', 2)
title('E(z, t)');
xlabel('z');
ylabel('E(z, t)');
legend('t=0', 't=10e-9', 't=20e-9');
 
subplot(2, 1, 2); plot(z, H1, z , H2, z, H3, 'linewidth', 2)
title('H(z, t)');
xlabel('z');
ylabel('H(z, t)');
legend('t=0', 't=10e-9', 't=20e-9');

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Question.

            Matlab 함수 중 plot3를 이용하여 E-field와 H-field를 도시하시오.

clc
clear
close all;
a= 1e2;
 
f = 10e6;
 
w = 2*pi*f;
E0 = 1;
e0 = 1e-9/(36*pi);
m0 = 4*pi*1e-7;
k = w*sqrt(m0*e0);
intrin = (w*m0)/k;
H0 = E0/intrin;
 
t1 = 0;
t2 = 10e-9;
t3 = 20e-9;
z = linspace(0, 100, 1e5);
 
E1 = E0*cos(w*t1-k*z);
E2 = E0*cos(w*t2-k*z);
E3 = E0*cos(w*t3-k*z);
 
H1 = H0*cos(w*t1-k*z);
H2 = H0*cos(w*t2-k*z);
H3 = H0*cos(w*t3-k*z);

Hy = zeros(1, length(z));
Ex = zeros(1, length(z));
 
plot3(z, E1, Hy, ':b',  z, E2, Hy, ':m', z, E3, Hy, ':g', z, Ex, H1, z, Ex, H2, z, Ex, H3, 
     'linewidth', 1.5)
grid on;
xlabel('z(m)');
ylabel('Ex(V/m)');
zlabel('Hy(A/m)');