www.pudn.com > loopantenna.rar > loop3.m, change:2002-04-17,size:1650b


%LOOP3 
%   Creates triangular mesh for the helical antenna  
%   of given radius, number of turns, spacing, and  
%   wire thickness. 
% 
%   LOOP3 has a somewhat better mesh quality than LOOP2  
%   (see the text of Chapter 5). Otherwise, both the scripts  
%   are equivalent.   
% 
%   The following parameters need to be specified: 
% 
%   Turn radius in m                        a 
%   Number of loop rectangles               M 
%   Width of the strip                      h 
%   Number of turns                         N 
%   Spacing between turns                   S 
% 
%   Note: the equivalent wire radius is 0.25*h 
% 
%   Copyright 2002 AEMM. Revision 2002/03/13  
%   Chapter 5 
 
clear all 
 
%Axial mode parameters 
a=0.0545;    
M=12;        
h=0.005;     
N=15;        
S=0.076;     
 
%pitch angle 
pitch=atan(S/(2*pi*a)) 
factor=sin(pitch); 
factor1=h*cos(pitch); 
 
L=N*S      %Total length of the antenna 
     
Count=1;    %Point number 
EN=1;       %Element number 
%Create rectangles 
t=[]; 
for n=1:M*N 
    angle =2*pi*(n-1)/M; 
    delta  =h*factor/a;  %correction angle in radians 
    Point1=[a*cos(angle) a*sin(angle) n*L/(M*N)-L/2]; 
    Point2=[a*cos(angle+delta) a*sin(angle+delta) n*L/(M*N)-L/2-factor1]; 
    X(Count:Count+1)=[Point1(1) Point2(1)]'; 
    Y(Count:Count+1)=[Point1(2) Point2(2)]'; 
    Z(Count:Count+1)=[Point1(3) Point2(3)]'; 
    if(n>1) 
        t=[t [Count-2; Count-1; Count+1] [Count-2; Count; Count+1]]; 
    end 
    Count=Count+2; 
end 
 
%Nodes 
PointNumber=Count-1; 
for L=1:PointNumber 
   p(1:3,L) = [X(L); Y(L); Z(L)]; 
end 
t(4,:)=1; 
 
%Save result 
save loop3  p t h; 
viewer('loop3')