Transient fields of concave annular arrays.

A new analytic expression for the impulse response of concave radiators is used to compute the transient pressure distributions of phased annular arrays with spherical geometry. The process of phasing the array to achieve variable focusing is treated by summing the delayed impulse responses of the individual annuli. The example of pressure distributions of a five element annular array is treated in detail, and some recommendations are given for practical computer studies.

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