Abstract: In accordance with the invention, the digital samples associated with each of the array elements arranged along a plurality of parallel lines are shifted by a distinct predetermined number of positions along each of said lines, and the digital samples of each line are added separately. Thereafter, each sum thus obtained is multiplied by a distinct phase coefficient. The signals thus obtained for each beam are all in phase. The lines of array elements that are electronically scanned can be oriented along any direction, and advantageously along one or a plurality of diagonals of the array and the electronic scanning of the array elements can be made separately along odd alternate diagonals and along even alternate diagonals.