diff --git a/RTX class/FarField.m b/RTX class/FarField.m
index bbe2ed59eb44441e55ae66728412a799d994cbba..c97bbc72302d976e6c66f4a9dfecd955e84da0ab 100644
--- a/RTX class/FarField.m	
+++ b/RTX class/FarField.m	
@@ -17,9 +17,10 @@ classdef FarField
                 c3 = c2*sin(theta(i));
                 for j = 1:nr
                     area = r(j) * c1;
+                    c4 = c3*r(j);
                     ind = 2*nr-j+1;
                     for k = 1:nfi
-                        field(i) = field(i) + histogram(ind)*exp(c3*r(j)*sin(fi(k)))*area;
+                        field(i) = field(i) + histogram(ind)*exp(c4*sin(fi(k)))*area;
                     end
                 end
             end