THE PERFORMANCE OF THE SPUD ALGORITHM DETECTING HARBOUR PORPOISE (PHOCOENA PHOCOENA) ECHOLOCATION CLICKS

摘要

The original POD design was produced nine years ago. Although there have been a number of later versions it is still based on comparing the outputs of a number of analogue filters to determine the presence of an echoloation click. The original proto-POD used a four filter system. It is believed the current POD uses a two filter system. The aim of the the Simple Porpoise Underwater Detector (SPUD) work was to attempt to make a detection system that would have the following characteristics (1) No operator controls (2) Good manufacturing reproducibility (3) All processing internal to unit (4) Easy deployment (5) Recovery aids to assist relocation (6) Small size Spud is a sub-set of a more advanced concept, the Complex Research Underwater Detector (CRUD). CRUD aims to detect and classify all echolocation and similar clicks while SPUD is highly optimised to detect only the echolocation clicks from the harbour porpoise. This paper describes the origins of the SPUD algorithm, how it operates and the results of testing with acoustic data containing harbour porpoise and other clicks.