Attenuation Coefficient Calculator on Matlab

attencoeff.m

% -------------------------------------------------------------------------
% | Attenuation Coefficient Calculator                                    |
% | ==================================                                    |
% | Olli Vanhoja                                                          |
% |                                                            2010-08-26 |
% -------------------------------------------------------------------------
clear all
close all
close all hidden
clc

% Parameters
f     = 1*10^9; % Frequency [Hz]
E_0   = 1;
x     = 1;       % Distance [m]
e_r   = 78;      % e_r'  (Real)
e_ri  = 0.1;     % e_r'' (Imaginary)
mu_r  = 1;
sigma = 4;       % Conductivity (sigma) [S/m]

% Constants
c_0  = 299792458;
mu_0 = 4*pi*10^-7;
e_0  = 1/(mu_0*c_0^2);

j = sqrt(-1); % Imaginary unit

eps   = e_0*e_r;
mu    = mu_0*mu_r;
omega = 2*pi*f;

gamma = j*omega*sqrt(mu*eps)*sqrt(1-j*(sigma)/(omega*eps));
E     = exp(-gamma*x)/E_0;
G     = 20*log10(exp(-real(gamma)));

fprintf('gamma = %f\nRe E = %e\nAttenuation = %f dB/m\n', real(gamma), real(E), G);

Thanks！