3D pattern rotation

Hello,

I have an exported radiation pattern with the following form: a T1 matrix [Nx3], where:

1st column Amplitude;

2nd column Theta (from -180 to 180);

3rd column Phi (from -90 to 90);

By using the following code:

figure();
patternCustom(T1(:,1),T1(:,2),T1(:,3));

I get the correct radiation pattern, which is the following:

My problems are the following:

1) When I use another way to plot the pattern, I get something which is deformed (not talking about the rotation, but the shape itself)

This is how I try to plot the second one:

th_a = 360/stepsize;
phi_a = 180/stepsize;

T2= zeros(phi_a+1,th_a+1);

for n=1:phi_a+1
    for i=1:th_a
        
        T2(n,i) = T1(i+((n-1)*th_a),1);
    end
end

theta = 0:stepsize:180;
phi = 0:stepsize:360;

freqVector  = [30 30.00005].*1e9;        % Frequency range for element pattern
antenna     = phased.CustomAntennaElement('FrequencyVector',freqVector, ...
                              'PatternCoordinateSystem','phi-theta',...
                              'PhiAngles',phi,...
                              'ThetaAngles',theta,...
                              'MagnitudePattern',T2,...
                              'PhasePattern',zeros(size(T2)));
                          
                          
fmax = freqVector(end);
figure();
pattern(antenna,fmax,'Type','powerdb')

I think it's related to the fact that in the second way, phi is required from 0:360 and theta from 0:180, while from the exported way, I have phi from -90:90 and theta from -180:180.

How can I solve this issue? Of course, this is not the main problem, considering the fact I can use the first representation. The main problem, which I think it's quite related, is that this happens also when I try to use the rotpat function.

2) If I use the rotpat function, I get something deformed as well.

el = -90:stepsize:90;
az = -180:stepsize:180;

newax=roty(90);
pat = rotpat(T2,az,el,newax);

for n=1:phi_a+1
    for i=1:th_a
        T3(i+((n-1)*th_a),1) = pat(n,i);
    end
end

figure();
patternCustom(T3(:,1),T1(:,2),T1(:,3));

How can I solve this issue? Of course, my main goal would be to rotate the radiation pattern.

Many thanks in advance.

[Yash Srivastava]

Hi John,

To have better understanding of your question, please provide T1 data.