Aperture and element minimization in linear sparse arrays with desired beam patterns

In this paper, an optimization method aimed at designing aperiodic linear sparse arrays is proposed that is based on the stochastic optimization methodology called simulated annealing. Such a method optimizes the positions and the weight coefficients of each element of a linear array in order to obtain a beam pattern that meets given requirements. Moreover, while positions and weights are optimized, minimization of both the number of elements and the spatial aperture is carried out. In this way, a beam pattern without grating lobes and close to the desired one is produced using a small number of elements and a short aperture. The results obtained are impressive in terms of improvement of array characteristics and performance over those reported in the literature, while a great flexibility in defining the desired beam pattern is allowed. Finally, it is proved that the array configurations need a number of elements very close to the absolute minimum to achieve the desired beam pattern.