LSI circuits for adaptive array processing in passive sonar

An important function in underwater passive listening is array processing. Its role is to distinguish, as far as possible, the acoustic targets present in the water. During the last two decades, much effort has been devoted to adaptive array processing to obtain better performance than with conventional beamforming, both in resolving power and protection against high-level sources. However, the amount of computation needed by this processing is great. To reduce the complexity of the processing, new algorithms have been developed. But for important applications, this is still not sufficient. To solve this problem, the processing scheme has been optimised in order to obtain a modular architecture by which systems can be built using the same elementary cascadable processor for many applications. The design of special LSI circuits for adaptive array processing is described and the performance advantages quantified.