  The modular design of planar phased array antennas with hexagonal apertures
is addressed by means of innovative diamond-shaped tiling techniques. Both
tiling configuration and subarray coefficients are optimized to fit
user-defined power-mask constraints on the radiation pattern. Toward this end,
suitable surface-tiling mathematical theorems are customized to the problem at
hand to guarantee optimal performance in case of low/medium-size arrays, while
the computationally hard tiling of large arrays is yielded thanks to an
effective integer-coded GA-based exploration of the arising high-cardinality
solution spaces. By considering ideal as well as real array models, a set of
representative benchmark problems is dealt with to assess the effectiveness of
the proposed architectures and tiling strategies. Moreover, comparisons with
alternative tiling architectures are also performed to show to the interested
readers the advantages and the potentialities of the diamond subarraying of
hexagonal apertures.
