Experimental Testing of the Developed Hydroacoustic Autonomous Combined System for an Underwater Acoustic Source Direction-Finding

This paper presents details on the developed autonomous hardware system which includes the combined receiving system (the vector sensor array, e.g. vector receiver, combined with an undirected hydrophone) and the system position sensors. The results of two unique experiments carried out in the shallow zone of the Vityaz Bay during the summer season are discussed in the paper. The experiments were aimed at the underwater acoustic source direction finding using the mentioned system. The towed narrow band electromagnetic source with the hydrostatic system for pressure compensation was used as a tracked source. Using the Goertzel algorithm for signal magnitude on specific frequency estimation and robust atan2 processing to determine the azimuthal angle to the source within a quadrant, it was found that the developed system makes it possible to estimate bearing on an underwater acoustic source with the precision of less than 10 degrees in more than 85% of the measurements in conditions of both experiments.