rcs_cylinder.m
上传用户:szahd2008
上传日期:2020-09-25
资源大小:1275k
文件大小:2k
- function [rcs] = rcs_cylinder(r1, r2, h, freq, phi, CylinderType)
- % rcs_cylinder.m
- % This program compute monostatic RCS for a finite length
- % cylinder of either cricular or elliptical cross-section.
- % Plot of RCS versus aspect angle theta is generated at a specified
- % input angle phi
- % Last modified on July 16, 2003
- r = r1; % radius of the circular cylinder
- eps =0.00001;
- dtr = pi/180;
- phir = phi*dtr;
- freqGH = num2str(freq*1.e-9);
- lambda = 3.0e+8 /freq; % wavelength
- % CylinderType= 'Elliptic'; % 'Elliptic' or 'Circular'
- switch CylinderType
- case 'Circular'
- % Compute RCS from 0 to (90-.5) degrees
- index = 0;
- for theta = 0.0:.1:90-.5
- index = index +1;
- thetar = theta * dtr;
- rcs(index) = (lambda * r * sin(thetar) / ...
- (8. * pi * (cos(thetar))^2)) + eps;
- end
- % Compute RCS for broadside specular at 90 degree
- thetar = pi/2;
- index = index +1;
- rcs(index) = (2. * pi * h^2 * r / lambda )+ eps;
- % Compute RCS from (90+.5) to 180 degrees
- for theta = 90+.5:.1:180.
- index = index + 1;
- thetar = theta * dtr;
- rcs(index) = ( lambda * r * sin(thetar) / ...
- (8. * pi * (cos(thetar))^2)) + eps;
- end
- case 'Elliptic'
- r12 = r1*r1;
- r22 = r2*r2;
- h2 = h*h;
- % Compute RCS from 0 to (90-.5) degrees
- index = 0;
- for theta = 0.0:.1:90-.5
- index = index +1;
- thetar = theta * dtr;
- rcs(index) = lambda * r12 * r22 * sin(thetar) / ...
- ( 8*pi* (cos(thetar)^2)* ( (r12*cos(phir)^2 + r22*sin(phir)^2)^1.5 ))+ eps;
- end
- % Compute RCS for broadside specular at 90 degree
- index = index +1;
- rcs(index) = 2. * pi * h2 * r12 * r22 / ...
- ( lambda*( (r12*cos(phir)^2 + r22*sin(phir)^2)^1.5 ))+ eps;
- % Compute RCS from (90+.5) to 180 degrees
- for theta = 90+.5:.1:180.
- index = index + 1;
- thetar = theta * dtr;
- rcs(index) = lambda * r12 * r22 * sin(thetar) / ...
- ( 8*pi* cos(thetar)^2* ( (r12*cos(phir)^2 + r22*sin(phir)^2)^1.5 ))+ eps;
- end
- end
- % Plot the results
- delta= 180/(index-1);
- angle = 0:delta:180;
- plot(angle,10*log10(rcs),'k','linewidth',1.5);
- grid;
- xlabel ('Aspect angle, Theta [Degrees]');;
- ylabel ('RCS - dBsm');
- title ([[CylinderType],' Cylinder',' at Frequency = ',[freqGH],' GHz']);