Weighting and thinning wide-band arrays by simulated annealing

In this paper, a novel algorithm based on simulated annealing is applied to optimize the performance of the wide-band linear transducer array. The algorithm allows optimization of the beam pattern (BP) by assigning the appropriate weight coefficients to each individual element of the array. It also allows the number of individual elements in the array to be minimized for a given BP profile. The BP of a fully optimized array having 94 elements over a 52-wavelength aperture is compared with the one corresponding to a conventional (dense) array transducer composed of 125 unapodized elements (62-wavelength aperture) and also with the BP of the same dense array with optimized weight coefficients. The results of the simulation indicate the applicability of the algorithm to obtain a BP with preset characteristics with respect to the main and side lobe levels. (C) 2002 Elsevier Science B.V. All rights reserved.