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I want to plot a 3D plot with polar parameters theta, phi and radius. I have calculated these 3 paraeters but I am not able to get a 3D plot.

I want a plot that would look like below figure.

I got this plot from PhaseShiftBeamformerUsingULAExample in matlab. I am not getting how did they got such a plot. Matlab code for it is below.

%% Phase-Shift Beamformer Using ULA
% Apply phase-shift beamforming to the signal received by a 5-element ULA.
% The beamforming direction is 45° azimuth and 0° elevation. Assume
% the array operates at 300 MHz. Specify the beamforming direction using an
% input port.

%%
% Simulate a sinewave signal arriving at the array.
clearvars;close all;
t = (0:1000)';
fsignal = 0.01;
x = sin(2*pi*fsignal*t);
c = physconst('LightSpeed');
fc = 300e6;
incidentAngle = [30;15];


array = phased.ULA('NumElements',5);
x = collectPlaneWave(array,x,incidentAngle,fc,c);
noise = 0.1*(randn(size(x)) + 1j*randn(size(x)));
rx = x + noise;

%%
% Construct the phase-shift beamformer and then beamform the input data.
beamformer = phased.PhaseShiftBeamformer('SensorArray',array,...
 'OperatingFrequency',fc,'PropagationSpeed',c,...
 'DirectionSource','Input port','WeightsOutputPort',true);
%%
% Obtain the beamformed signal and the beamformer weights.
[y,w] = beamformer(rx,incidentAngle);
%%
% Plot the original signal at the middle element and the beamformed signal.
figure();
plot(t,real(rx(:,3)),'r:',t,real(y))
xlabel('Time')
ylabel('Amplitude')
legend('Original','Beamformed')

%%
% Plot the array response pattern after applying the weights.
figure();
pattern(array,fc,[-180:180], [-90:90],'PropagationSpeed',c,'CoordinateSystem','polar','Weights',w,'Type','efi eld')

The example code uses the pattern command from the phased array toolbox. That is pretty specific for their application.

I would just take theta, phi and r and convert them to Cartesian coordinates and plot them using surf or surfl:

[theta,phi]=meshgrid(linspace(-pi/2,pi/2),linspace(0,2*pi));
r=1+sin(theta*3).*cos(phi*2);
X=cos(theta).*cos(phi).*r;
Y=cos(theta).*sin(phi).*r;
Z=sin(theta).*r;
surf(X,Y,Z)

One can of course also be lazy and use sph2cart (note that Matlab has the opposite notation of angles from me):

[X,Y,Z] = sph2cart(phi,theta,r);