Comparison of Sonar Discrimination: Dolphins and an Artificial Neural Network

摘要

The capability of an echolocating dolphin to discriminate differences in the wallthickness of cylinders (3.81 cm o.d. and 12.7 cm length) was determined by Au and Pawloski J. Comp. Physiol. A 170, 41-47 (1992). The dolphin was required to discriminate a standard target from comparison targets of differing wall thicknesses. Performance varied from 96% to 56% correct depending on the wall thickness of the comparison targets. The 75% correct threshold was determined to be wall thickness differences of 0.23 mm for comparison targets with thinner walls and +0.27 mm for comparison targets with thicker walls than the standard. The dolphin performance was unchanged in the presence of artificial broadband masking noise until the echo-energy-to-noise ratio fell below approximately 15 dB. A counterpropagation artificial neural network was used to examine broadband echo features from the same cylinders. Features of the echoes were determined by passing them through a filter bank of constant-Q filters.