Abstract:
: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.
journal_name
Ultrasonicsjournal_title
Ultrasonicsauthors
Trucco Adoi
10.1016/s0041-624x(99)00089-xsubject
Has Abstractpub_date
2000-03-01 00:00:00pages
161-5issue
1-8eissn
0041-624Xissn
1874-9968pii
S0041-624X(99)00089-Xjournal_volume
38pub_type
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