near field to far field transformation in matlab

To perform near field to far field transformation in MATLAB, you can use the Fraunhofer approximation method. Below is an example code that demonstrates how to do this:

main.m
% Define the near field signal
nearFieldSignal = ... % Insert your near field signal here

% Define the wavelength of the signal
wavelength = ... % Insert the wavelength of the signal in meters

% Define the distance from the near field to the far field region
distance = ... % Insert the distance from the near field to the far field region in meters

% Calculate the wave number
waveNumber = 2 * pi / wavelength;

% Calculate the far field signal using Fraunhofer approximation
farFieldSignal = nearFieldSignal .* exp(1i * waveNumber * distance) / (1i * wavelength * distance);

% Plot the near field and far field signals
figure;
subplot(2,1,1);
plot(nearFieldSignal);
xlabel('Sample');
ylabel('Amplitude');
title('Near Field Signal');
subplot(2,1,2);
plot(farFieldSignal);
xlabel('Sample');
ylabel('Amplitude');
title('Far Field Signal');
843 chars
28 lines

Make sure to replace the nearFieldSignal, wavelength, and distance variables with your actual values.

This code assumes that the near field signal is represented as a vector in the variable nearFieldSignal, the wavelength of the signal is given in the variable wavelength, and the distance from the near field to the far field region is given in the variable distance.

The far field signal is calculated by multiplying the near field signal by the exponential term exp(1i * waveNumber * distance) and dividing by the term 1i * wavelength * distance. The exponential term represents the phase shift introduced due to the distance, and the dividing term compensates for the attenuation due to the distance.

The code also includes a plot of both the near field and far field signals for visualization purposes.