PC based data acquisition and signal processing for underwater sensor arrays

Analog signals can be acquired and processed by using PC based data acquisition (DAQ) systems. These data acquisition and processing systems can offer design flexibility and cost advantage by using commercial-off-the-shelf (COTS) data acquisition boards. Today Intel based multi-core processors have acquired the capability to perform signal processing functions on the digitized data of multi-channel underwater surveillance systems. A major concern is acquisition of data from an underwater sensor array having multiple analog input channels. Mostly underwater arrays have more number of analog inputs than the maximum number of analog inputs present on a commercially available data acquisition board. This requires a PC based system utilizing multiple data acquisition boards. This paper presents a 96 channel data acquisition system comprising of Intel processor based industrial PC mainframe running Windows. The suggested system consists of three PCI data acquisition boards for acquiring 96 channels of acoustic data. The suggested system performed frequency domain beamforming algorithm on the digitized data that resulted in 96 beams shown in a MATLAB window.