基于matlab的抛物面反射器的孔径效率.zip

% Ismail Mohamed Ibrahim Elbadawy % AAST % This code is designed to plot aperture effeciency Vs subtended angle % for parabolic reflector using different values of n (2,4,6,8). % You can see the same output in "Antenna Theory",Constantine A.Balanis % Third edition page 914. % ------------------------------------------------------------------- clc clear all close all fprintf('<< --------- PLEASE BE PATIENT --------- >>') thetao=0:90; % Subtended angle in degrees syms theta for j=1:4 n=j*2; g=2*(n+1)*((cos(theta))^n); % Feed Pattern h=sqrt(g)*tan(theta/2); for i=1:length(thetao) angle=thetao(i)*(pi/180); % From degree to radian % Aperture effeciency calculation eff(i)=((cot(angle/2))^2)*((abs(eval(int(h,theta,0,angle))))^2); end if j==1 plot(thetao,eff,'b','linewidth',2) hold on elseif j==2 plot(thetao,eff,'k','linewidth',2) hold on elseif j==3 plot(thetao,eff,'r','linewidth',2) hold on else plot(thetao,eff,'g','linewidth',2) grid on end end legend('n=2','n=4','n=6','n=8') xlabel('Reflector half-angle (degrees)') ylabel('Aperture effeciency')