Apodization is a digital signal processing (DSP) operation which is used when windowing temporal signal for different operations, the most famous one is the Short Time Fourier Transform. There are various apodization schemes, spanning from simple box functions to more complex structures. The apodization function must be used and constructed very carefully. For example, using a box function in DSP would probably cause lateral lobes as the transformation in the frequency domain creates a sinc function.