Approach to an electro-acoustic system

The Marconi Company, with the support of the Ship and Marine Technology Requirements Board of the Department of Industry, has developed an acoustic positioning system for floating vessels. Among other principles used, a variant of the superhet´ receiver is employed in the task of detecting acoustic signals in the sea. The end product is a method of extremely accurate local navigation of surface vessels relative to the ocean floor. Since 1962, in this and other applications, the system has demonstrated its abilities of reliable detection if there are multiple signals in the presence of background noise, and accurate timing of signal arrival and freedom from false recognitions which are generated either by noise or crosscoupling between channels. This, the most recent application, saw its inception with the upsurge in offshore exploration when dynamic positioning of ships became a desirable facility.