Active transducer assembly for a phased array depth sounder

Abstract

A phased array acoustic transducer apparatus has a controller and an array of ultrasonic transducers mounted in a water tight housing. Also included in the water tight housing are a transmitter circuit which sends phased excitation signals to the array of ultrasonic transducers so as to generate a directed beam of acoustic energy. A receiver circuit, located in the water tight housing, processes and combines signals received by the array of ultrasonic transducers to generate an output signal. The controller sends both power and control signals via a cable to the transmitter and receiver circuits. The cable uses a simple serial data line and a clock signal line to transmit beam angle control signals, thereby minimizing the size of the cable. The controller sends transmitter gating signals over a gate signal line on the cable to enable and disable operation of the transmitter circuit, such as is required for a pulse-echo mode of operation. In a preferred embodiment, the system includes a display unit coupled to the controller. The controller automatically sends a sequence of control signals that cause the transmitter circuit, in conjunction with the array of ultrasonic transducers, to generate a sequence of directed beams of acoustic energy. The controller automatically collects the resulting output signals from the receiver circuit and generates therefrom a corresponding image on the display unit.