System and method for estimating an angle of arrival

A system, comprising:

• an array antenna;
• a radio frequency (RF) front end;
• and
• a processing circuit,
• the array antenna being curved,
• the array antenna comprising a plurality of radiators, including a first radiator having a first resonant frequency and a second radiator having a second resonant frequency different from the first resonant frequency, the plurality of radiators comprising at least 10 radiators,
• the processing circuit being configured to receive a signal from the array antenna and to calculate, from the signal, an estimated angle of arrival of electromagnetic radiation corresponding to the signal,
• wherein:
• the array antenna comprises a substrate integrated waveguide,
• the substrate integrated waveguide has the shape of a hollow cylinder,
• the array antenna has a first feed and a second feed,
• the two feeds are at diametrically opposed positions on the hollow cylinder, and
• the calculating of the angle of arrival comprises calculating a normalized cross correlation vector, the normalized cross correlation vector comprising, for each of a plurality of frequency points, a normalized cross correlation of a signal at the first feed and a signal at the second feed.