Electromagnetic Waves

Project

Backward Waves


Overview

Work in assigned project groups. 

The objective of this project is to simulate backward waves.

NOTE: Use the Project Report Template

IN NO CASE may code or files be exchanged between students, and each student must answer the questions themselves and do their own plots, NO COPYING of any sort! Nevertheless, students are encouraged to collaborate in the lab session.



Part 1: Simulation

% backward wave
clear all
close all

w1=2*pi*10^9    %frequency 1 in rad/s
w2=1.05*w1      %frequency 2  in rad/s
c=3*10^8        %speed of light in m/s
vp1=c/2         %phase velocity at w1 in m/s
b1=w1/vp1       %propagation constant at w1
lam1=2*pi/b1    %wavelength lambda1 in m
vp2=1.1*c/2/0.95         %phase velocity at w2
b2=w2/vp2       %propagation constant at w2
vg=(w2-w1)/(b2-b1) %group velocity = d omega / d beta
lam2=2*pi/b2    %wavelength lambda2

numx=250   %num of spatial points in plot
numt=200   %num of spatial points in plot
dx=lam1/5/4 %spatial separation of points in plot
dt=0.1/10^9    %time separation of movie frames in plot movie
for nt=1:numt;
    for nx=1:numx;
        t=nt*dt; x=nx*dx; xx(nx)=x;
        y(nx)=real( exp(i*(w1*t-b1*x)) + exp(i*(w2*t-b2*x)) );
    end;
    plot(xx,y);axis([0 dx*numx -2 2]);
    pause(0.1)
    mov(nt) = getframe;
end;

h2=figure(2);
movie(mov);
v = VideoWriter('backwave','MPEG-4');
open(v);
writeVideo(v,mov);
close(v);


Save your files and plots before exiting 

Part 2: Simulation of forward ("normal") waves

Report Data


NOTE ReportTemplate: Use the Project Report Template 

  YOU MUST ADD CAPTIONS AND FIGURE NUMBERS TO ALL FIGURES!! 

Copyright 2010-2019 T. Weldon

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