Illustrations on MRI Techniques Using Matlab - Digital Signal Processing for Medical Imaging Using Matlab - page 64

Fig. 3.8 Illustration of the original and the reconstructed spatial domain (proton-density) from the
polar scanned K-space G ( r ,θ)

%d2=1;
B0=1;
n=ones(3,25)*2;
for i=1:1:10
n=[n;ones(1,25)*i];

end
for i=10:-1:1
n=[n;ones(1,25)*i];

end
n=[n;ones(2,25)*1];
POS=[];
for x=1:1:siz
for y=1:1:siz
for i=1:1:n(x,y)

% k(x,y,i)=rand*2-1; %With dephasing

k(x,y,i)=0; %Just to check the validity of the program
end

end

end
KSPACE=zeros(101,180);
for r=0:(13/100):13
r1=round((r)*(100/13)+1);
for theta=-pi:(2*pi)/179:pi
theta1=round((theta+pi)*(179/(2*pi))+1);
Gx=r*cos(theta)

;

Gy=r*sin(theta);
Gx1=Gx/(10ˆ3);
Gy1=Gy/(10ˆ3);
POS=[POS;
Gx Gy];

temp=0;
for x=0:1:24
for y=0:1:24
for i=1:1:n(x+1,y+1)
phi1=k(x+1,y+1,i)*0.1*2*pi;
%x-Gradient and y-Gradient are applied simultaneously for the duration of
%0.1