Design and development of a Giga-bit Ethernet based high speed broadband data acquisition system for an underwater imaging array

Ambient Noise Imaging (ANI) has been an active area of research at the Acoustic Research Laboratory (ARL). The ARL under Tropical Marine Science Institute (TMSI) of National University of Singapore (NUS) had designed an ambient noise imaging array in 2003 and tested them in the field. To cater for a high data-rate of 1.6 Gbps, Fibre Channel Arbitrated Loop technology was employed. Although this arrangement satisfied the data-rate requirement, the resulting complexity, size, and huge power requirements of the system along with a lack of reliability still needed to be addressed. The recent availability of relatively low cost, small form-factor, multi-channel off the shelf data acquisition cards and low power PC104+ embedded platforms along with Giga-bit Ethernet technology has been used to address the limitations of earlier system. The use of embedded Linux operating system has helped in improving the reliable operation of the system. In this paper we give a detailed account of the new hardware & software design and implementation followed a performance assessment of the system through evaluation in the field.