A computer simulation study on the effects of multifrequency and aperiodic ultrasonic transducer arrays has shown that both methods improve grating lobe response when compared to a periodic array of the same aperture and element spacing. The multifrequency array produces a better beam pattern than either the aperiodic or combination aperiodic/multifrequency array. Both the aperiodic and multifrequency arrays have a narrower main lobe and higher side lobe response than a periodic array with reduced element spacing and an equal number of elements.
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