الفهرس 
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Abstract
Medical imaging modality is a fast-growing called by ’3D Ultrasound imaging ’. There
are many advantages (Iow cost, non-ionizing beam, portability) that allow representing the
anatomical structures in to three-dimensional that is natural form. Two-dimensional matrix
arrays replace it by relatively slow mechanical scanning probes. This two-dimensional matrix
arrays stretched in both elevation and lateral directions of the normal unidirectional probe.
The steering of the beam is allowed in the whole space by this 20 positioning of the
elements. 20 array probe has piezoelectric elements which are aligned on a regular grid and
inter-element distance called ’pitch’ and pitch must be < 1.J2 to limit the grating lobes level.
ID probe ofN elements the equivalent in 20 contains N x N = N2 elements where: N equal to
or more 128 elements. To c.’t>c’nnect this high number of elements in real world is technically
challenging. That is because the channels number in current scanners not often surpasses 256.
Generally, sparse array is used in controlling this type of probe implementation that
imposes multiplexing or reduced number of elements. This method is random selection
methods. These methods are disadvantaged by a lower signal to noise ratio due to the energy
losses that is related with the lower active element’s number. The best solution is
optimization to limit loss of performance.
An attractive advance in this field is 20 scanner probes with 3D imaging. Main
problems to implement these probes come from large number of elements that need to use
. When the number of elements is reduced the side lobes arising from the transducer changes
along with the grating lobes that are linked to elements periodical disposition. Grating lobes
are reduced by placing elements without any grid consideration. In this study, Binary Bat
Algorithm (BBA) is used to optimize the number of active elements in order to decrease side
lobe level with same main lobe. Results are compared to another optimization method to
validate the proposed algorithm like Genetic Algorithm (GA) and Binary Differential
Evolution Algorithm (BDE).