how to plot loadpull contour by smith chart?

i have a data with loadpull measurement result

vswr, phase and result (gain / aclr / pae data)

i import data below code

clear, close all
T = readtable('P:\MATLABData\LoadPull_HB_2640_32dbm.xlsx')
A = table2array(T);
Gvswr = A(:, 8);
Gmag = A(:, 9);
Gphase = A(:, 10);
Greal = Gmag.*cosd(Gphase);
Gimag = Gmag.*sind(Gphase);
ACLR = A(:, 17);
EVM = A(:, 13);
PAE = A(:, 14);
POUT = A(:, 11);
GAIN = A(:, 12);
CURRENT = A(:, 25);

...

now i dont know how to plot contour by smith chart?

i find other answer..but it could be only polar othogonal coordinate plot..

I want to plot in smith chart.

Answer 1

[Anurag Ojha]

Hello,

As per my understanding, you are trying to plot load loadpull contour by smith chart. To plot contours on a Smith chart, you can use the “smithplot” function available in the RF Toolbox of MATLAB. Here's an example of how you can modify your code to plot contours on a Smith chart:

% Load the data from the Excel file
T = readtable('P:\MATLABData\LoadPull_HB_2640_32dbm.xlsx');
A = table2array(T);

% Extract the required data
Gvswr = A(:, 8);
Gmag = A(:, 9);
Gphase = A(:, 10);
Greal = Gmag .* cosd(Gphase);
Gimag = Gmag .* sind(Gphase);
ACLR = A(:, 17);
EVM = A(:, 13);
PAE = A(:, 14);
POUT = A(:, 11);
GAIN = A(:, 12);
CURRENT = A(:, 25);

% Create a Smith chart
figure;
smithplot;

% Plot contours on the Smith chart
hold on;
contour(Greal, Gimag, GAIN);
colorbar; % Add colorbar to show the contour values
title('Gain Contours on Smith Chart');
xlabel('Real Part');
ylabel('Imaginary Part');
hold off;

For more information you can go through following MATLAB documentation.

• smithplot

Hope it helps!

[Rebecca McCabe]

I was initially confused by this because I was trying to make a contour plot where X and Y represented the real and imaginary part of z. Nothing would show up on the smith chart. But when I zoomed out, there was a contour plot outside of the plot.

Then I realized that X and Y refer to the real and imaginary part of gamma, not of z, when using this smith plot. So X and Y should range between 0 and 1 only in order for the data to show up on the plot.