Problem In Generating Proper Contour Plot from Radiation Pattern

I am Implementing following equation which describes the focal region field of reflector antenna.the code for this is as below

% % This program is developed by Balvant Makwana % % which explains the electric field distribution in focal region field

clc; close all; clear all;

 u= linspace(-10,10,2000); % distance from focus right now it is not normalised
 to=4;
% theta= input('enter the value of theta in degree (in practice theta do not exeed 50)   ');
% phi= input('enter the vaue of Phi in degrees (90) ');
theta=40;
phi=90;
J1 = besselj(1,u);
J2 = besselj(2,u);
Ex=2*(J1./u)+1i*[(4/to)*tan(theta/2).*(J2./u)*cos(phi)];
Ey=-1i*(4/to)*tan(theta/2).*(J2./u)*sin(phi);
Ez=-1i*(4/to)*(J2./u)*sin(phi);
Ex_log =20*log(Ex);
Ey_log=20*log(Ey);
Ez_log=20*log(Ez);
figure(1);
plot(u,Ex_log);
hold on;
plot(u,Ey_log,'-r');
%figure(2);
plot(u,Ez_log);
xlabel('distance from Focus');
title('Electric Field Distribution of Reflector');
hold off;

%for contour plot abs_Ex_log=abs(Ex_log); abs_Ey_log=abs(Ey_log); lx=abs_Ex_log; ly=abs_Ey_log;

% % lx=Ex_log; % % ly=Ey_log;

% z=repmat(abs_Ex_log,size(u));

% xv = abs_Ex_log .* cos(theta); % // 2D Cartesian coordinates % yv = abs_Ex_log .* sin(theta); % // 2D Cartesian coordinates % % % % % phi = -pi:.01:pi; % // 3D revolution angle around theta = 0 % % % % % // 3D points of the surface % xf = repmat(xv',size(u)); % yf = yv' * cos(phi); % zf = yv' * sin(phi); % [x,y] = meshgrid(xf,yf); % % mesh(xf,yf,zf)

[X,Y]= meshgrid(u,u); Zx= lx'*lx; Zy=ly'*ly;

% figure(2) % surfc(X,Y,Zx) % colormap hsv

 figure(3);
csx=contour(X,Y,Zx,20);
hold on;
csy=contour(X,Y,Zy,20);

i am getting the required plot(pattern) but contour plot is not proper. i am getting contour plot as shown

 the actual contour plot should be as  below

someone please do correction in code i have tried lot but couldn't rectify the problem