Rotationally symmetric planar ultra-wideband array design techniques

Rotational symmetry has often been observed in the design of ultra-wideband planar array layouts which use certain aperiodic tiling techniques and their variants. The use of rotational symmetry in these designs, however, has mainly been considered incidental and not of primary concern. Here, rotational symmetry is specifically exploited for not only placement of the array elements, but for fast calculation of their associated array factors. Two design techniques are presented that employ rotational symmetry in this fashion. One technique uses an advanced optimization strategy for element arrangement, while the other uses densely-packed semi-periodic sections to enable high-directivity and easy manufacturing.