Instrumentation for ocean acoustic tomography

A test ocean acoustic tomography experiment was conducted in the southern North Atlantic during 1981. Travel time variations of pulse-like signals transmitted between moored acoustic sources and receivers separated by hundreds of kilometers were used to image the intervening sound speed field. Intelligent sources, receivers, mooring positioning monitoring systems and precision time-keeping devices were developed specifically for this application. In this paper we describe the design of these instruments and we present examples of their use in the tomography experiment to show satisfactory overall system performance.