Radar Cross Section (RCS) - MATLAB Simulations for Radar Systems Design - page 562

val2m = 8. * pi * sin(aspect) * (tan(aspect)^2);
rcs_mu(index) = val1m / val2m + eps;
end
end
% Compute RCS using Eq. (2.35) (theta=0,180)
rcsdb = 10. * log10(rcs_po);
rcsdb_mu = 10 * log10(rcs_mu);
angle = 0:.1:180;
plot(angle,rcsdb,'k',angle,rcsdb_mu,'k-.')
grid;
xlabel ('Aspect angle - degrees');
ylabel ('RCS - dBsm');
legend('Using Eq.(11.37)','Using Eq.(11.36)')
freqGH = num2str(freq*1.e-9);
title (['Frequency = ',[freqGH],' GHz']);
Listing 11.8. MATLAB Function Ðrcs_frustum.mÑ
function [rcs] = rcs_frustum (r1, r2, h, freq, indicator)
% This program computes the monostatic RCS for a frustum.
% Incident linear Polarization is assumed.
% To compute RCP or LCP RCS one must use Eq. (11.24)
% When viewing from the small end of the frustum
% normal incidence occurs at aspect pi/2 - half cone angle
% When viewing from the large end, normal incidence occurs at
% pi/2 + half cone angle.
% RCS is computed using Eq. (11.43). This program assumes a geometry
format long
index = 0;
eps = 0.000001;
lambda = 3.0e+8 /freq;
% Enter frustum's small end radius
%r1 =.02057;
% Enter Frustum's large end radius
%r2 = .05753;
% Compute Frustum's length
%h = .20945;
% Comput half cone angle, alpha
alpha = atan(( r2 - r1)/h);
% Compute z1 and z2
z2 = r2 / tan(alpha);
z1 = r1 / tan(alpha);
delta = (z2^1.5 - z1^1.5)^2;
factor = (8. * pi * delta) / (9. * lambda);