DESCRIZIONE
A method and apparatus for detecting and classifying submerged swimming object from a passive signal generated by, and an active signal reflected from the object. In a first input of a passive mode branch a first signal representative of the passive signal is received. A second signal representative of the active signal is received in a second input of an active mode branch. In the active mode branch, the first signal is processed to generate a first classification estimate output, with first clues, of the most probable class of target for the object. In the passive mode branch, the second signal is processed to generate a second classification estimate output, with first clues, of the most probable class of target for the object. Both estimate outputs are received in a merger, for generating a merged classification estimate output with clues, which is input to a joint classifier that classifies the object.