# Is there a term called “Fourier Beamforming”?

I understand delay and sum beamforming, where we want to add the signals obtained from different sensors. But adding different time samples from different element of the array depending on the angle we are interested. For broadside or zero degree we would add the samples from the same time instant from each element of the array. On the other hand if we are interested to beamform in a particular angle there would be time delay between the samples of each element.

The question where "Fourier beamforming" comes into this picture? I have seen this term in many places. Any comment would be appreciated.

## 1 Answer

I'm guessing it's used in the following context.

Assuming you have a physical source with some of an amplitude distribution in a plane: you can calculate the polar pattern of that source simply as the Fourier Transform of the amplitude distribution as a function of space (not time!).

Fourier Beamforming would be the inverse process: you start with the desired polar pattern and do an in inverse Fourier Transform: that gives you the desired in amplitudes as a function of space, i.e. it tells where to put sources or sensors and what weights to apply.

• Does it have any relation to delay and sum Beamforming? For narrow-band is both are equivalent? – Creator Mar 24 '20 at 19:06