A novel method for measuring phase and sensitivity of long focused acoustic array

Establishing phase and shading for long focused arrays at high frequencies in acoustic test pools presents numerous problems. Conventional methods for using a plane wave produced by placing projectors in the far field or using collimators proves difficult to align and becomes expensive. A novel solution has been developed by the Naval Coastal Systems Laboratory. The approach employs an apparatus which is attached directly to the face of the array and measures the phase and sensitivity of each element of the array in the laboratory, without utilizing a transducer test pool.