A new method for designing acoustic phased arrays considering differences among vibration velocities of elements caused by mutual interaction

A new method for designing an acoustic phased array is proposed. The influe nce of acoustical mutual interactions on the vibration velocity of each ele ment is considered, Because of the mutual interactions among the elements, differences among actual vibration velocities and certain vibration velocit ies assumed in a conventional design method occur even if the elements are driven by the same electrical condition. The influence of the mutual radiat ion impedance on the vibration velocity is obtained using an equivalent cir cuit of the element. The vibration velocities in the (4,1) mode and the (2, 2) mode phased arrays an analyzed as functions of the phase angle of the dr iven voltage. The reason why the differences among the vibration velocities reach maxima in the vicinity of the resonance frequency is confirmed. The theoretical radiation power, which is changed by the vibration velocities d etermined by this method, agrees with the experimentally measured radiation power; thus the validity of this method is verified.