High performance signal acquisition systems for sonar applications

Examines the technology/complexity balance in high performance sonar data acquisition systems and describes the development of signal conditioning and A-to-D convertor systems using multi-loop, oversampled sigma-delta convertor techniques, and low complexity digital combiners and recursive interpolators. Various realisations of the basic circuit have been developed for a number of particular applications, using mixtures of thick film, surface mount and VLSI ASIC technologies. It is demonstrated that low cost signal acquisition systems, with dynamic ranges up to 120 dB and power per sensor requirements of the order of a few milliwatts, can be routinely produced on available technologies using these techniques